JP2005253284A - Power supply - Google Patents

Abstract

The present invention stabilizes current control in a power supply device having power factor improving means and facilitates compliance with power supply harmonic regulations.
When an input power source 1 is converted into a DC voltage and a voltage of a load 4 is obtained by a boost chopper circuit 3, a switching element 3c of the boost chopper circuit 3 is switched and short-circuited via a boost choke coil 3a. Improve rate. At this time, the control unit 13 that controls the power supply device turns the switching element 3c on and off based on the comparison result between the input current detected by the input current detection unit 10 and the sine wave input current reference signal, while the AC power supply half cycle. Every time, the switching element 3c is switched a predetermined number of times from the zero cross detection by the power supply phase detection circuit 5, and thereafter the switching is prohibited, so that the number of switchings per half cycle of the AC power supply does not vary.
[Selection] Figure 1

Description

  The present invention relates to a power supply circuit control technique for converting a commercial power supply into a power supply for home appliances, and more particularly to a power supply device having a boost chopper type power factor improvement and harmonic current suppression function.

  As an example of this type of power supply device, as shown in FIG. 23, an input power supply (commercial power supply) 1 is full-wave rectified by a rectifier circuit 2, and this AC / DC converted voltage is used as a boost chopper circuit (power factor improving means). 3) The voltage is boosted to a predetermined voltage in step 3, the power factor of the power source is improved, and the harmonic current is suppressed.

  In this case, the boost chopper circuit 3 includes a boost choke coil (reactor) 3a connected in series to the positive terminal side of the rectifier circuit 2, a reverse blocking diode 3b connected in series to the boost choke coil 3a, and the boost choke coil 3a A switching element (for example, IGBT; insulated gate transistor) 3c connected between the reverse blocking diode 3b on the negative terminal side of the rectifier circuit 2 and a smoothing capacitor 3d for smoothing the output voltage are provided.

  The operation of the step-up chopper circuit 3 is switched and short-circuited by the switching element 3c through the step-up choke coil 3a, while the switched voltage is supplied from the reverse blocking diode 3b to the smoothing capacitor 3d and the voltage of the load 4 is increased. To do. As the load 4, for example, an inverter circuit 4a and a motor 4b can be assumed when applied to a compressor motor of an air conditioner.

  The applicant has previously filed Japanese Patent Application No. 2002-158653 for a method of controlling a power supply device including such a boost chopper circuit 3. The prior invention will be briefly described with reference to FIGS. 24 to 26. First, when an AC power source is converted into a DC voltage to obtain a load voltage, the converted voltage is passed through at least a reactor (step-up choke coil 3a). To improve the power factor.

  The power supply device includes a power supply phase detection circuit 5 that detects a zero cross of the AC power supply 1, a current sensor 6 that detects an input current Ii of the boost chopper circuit 3, detection values thereof, and an input voltage of the boost chopper circuit 3. A control unit 8 that controls the switching element 3c based on Vi and the output voltage Vo, and a drive unit 7 that drives the switching element 3c by a signal from the control unit 8 are provided.

  The control unit 8 switches the switching element 3c of the boost chopper circuit 3 and turns on / off the switching element 3c based on the comparison result between the input current and the sine wave input current reference signal, and outputs the boost chopper circuit 3 The voltage Vo is a load voltage.

  At this time, as shown in FIG. 24, the deviation between the output voltage command value and the detected output voltage Vo is calculated by the calculating means 8a, and the amplitude value of the input current reference signal Ir is calculated by the current reference signal amplitude creating means 8b based on this calculated deviation. (A so-called reference sinusoidal amplitude value) is created.

  The multiplication of the created amplitude value and the detected input voltage Vi is performed by the multiplying means 8c, and hysteresis is created by the hysteresis comparator 8d based on the input current reference signal (current command value) and the current detected value Ii obtained as a result of the multiplication. The upper limit value and the lower limit value of the input current are created by this hysteresis, that is, the switching element 3c is switched so that the input current Ii is within the range of the upper limit value and the lower limit value.

  On the other hand, the zero cross of the AC power supply is detected by the power supply phase detection circuit 5, and a predetermined period from a predetermined time before the zero cross to the zero cross is generated by the switching operation prohibition time generating means 8e. It is prohibited by the AND circuit 8f.

  As a result, as shown in FIGS. 25 and 26, switching of the switching element 3c is prohibited only during the prohibited period, so that the input current is forcibly set to zero at the zero cross point of the input AC power supply, and the input in the vicinity of the zero cross point is performed. The AC waveform is improved (sinusoidal), and higher harmonic current can be reduced.

  However, in the control of the step-up chopper circuit 3, in the vicinity where the input voltage Vi becomes larger than the output voltage Vo (Vi ≧ Vo interval; peak region of the input current Ii), the input voltage or the output voltage varies, or the load 4 varies. Therefore, when the input current Ii reaches the lower limit value and the switching frequency of the switching element 3c increases, a problem due to the current control occurs.

  For example, as shown in FIG. 25, when the input current Ii does not reach the lower limit value (that is, when the negative direction fluctuation is small), the switching frequency of the switching element 3c does not increase. Compared with this, as shown in FIG. 26, when the input current Ii is at the lower limit value, the switching frequency of the switching element 3c increases, that is, the switching frequency for each half cycle of the AC power supply is different and varies without being constant. To do.

  The fact that the number of times of switching in each half cycle of the AC power supply fluctuates means that the current control is not stable, not only hinders the reduction of high-order harmonic current, but also makes it difficult to clear power supply harmonic regulations. Further, even if the switching is performed once, the output voltage is affected, so that stable load power supply cannot be performed. In particular, when the load 4 is a motor, the motor rotation speed is not stable, which causes noise and the like.

  In order to solve the above-described problems, the present invention provides a power supply apparatus that improves the power factor by short-circuiting the converted voltage through at least a reactor when converting the AC power supply into a DC voltage to obtain a load voltage. And switching the switching element of the power factor improving means including the reactor, and turning on and off the switching element according to the comparison result between the input current and the input current reference signal of the power supply voltage waveform. While the output voltage is used as a load voltage, a zero cross of the AC power supply is detected, and the switching element is switched a predetermined number of times based on the zero cross detection.

  When switching of the switching element is started by the zero cross detection, the start time is set to a predetermined positive value or negative value with respect to the zero cross detection, and the switching start time of the switching element is the load or input of the power supply device. It is preferable to change according to the magnitude of the current.

  The switching frequency of the switching element is set so that the switching operation is completed within 90 degrees of the power supply phase of the AC power supply, and the switching frequency of the switching element is at least the magnitude of the load and input current of the power supply device. Or it is preferable to determine based on a power supply frequency, or to determine combining them.

  Further, when setting the number of times of switching, when the load of the power supply device is a motor via inverter means, it is preferable to obtain it based on the motor rotation speed or the inverter output frequency.

  It is preferable that the switching frequency of the switching element and the subsequent switching inhibition control are realized by software, and further provided with voltage detection means for detecting the voltage of the AC power supply, and the switching frequency of the switching means is determined by this detection voltage. .

  It is preferable that the switching operation of the switching element is completed in a predetermined period after the zero cross detection.

  It is preferable to adjust the switching frequency of the switching element so that the switching operation of the switching element is completed in the predetermined period.

  When the switching operation of the switching element is performed after the predetermined time, it is preferable to perform the switching operation of the switching element by reducing the switching frequency by a predetermined number of times from the previous switching frequency.

  When the switching operation of the switching element is completed before the predetermined time, it is preferable to perform the switching operation of the switching element by increasing the switching frequency by a predetermined number of times from the previous switching frequency.

  When the switching operation of the switching element is not completed in the predetermined time as a result of changing the number of times of switching of the switching element, it is preferable to provide means for correcting the predetermined time.

  The number of switching times of the switching element is counted by a counter function, and the count function is preferably reset by the zero cross detection.

  The present invention relates to a power supply device that improves the power factor by short-circuiting the AC power source via a reactor when converting AC voltage to DC voltage to obtain a load voltage. From the comparison result of the input current and the input current reference signal of the power supply voltage waveform, the switching element is turned on and off to set the output voltage of the power factor improving means as the load voltage, while the AC power supply It is preferable that a zero cross is detected, and after a predetermined time has elapsed since the zero cross is detected, the switching operation of the switching element is completed by the next switching off signal of the switching element.

  The present invention relates to a power supply device that improves the power factor by short-circuiting the AC power source via a reactor when converting AC voltage to DC voltage to obtain a load voltage. From the comparison result of the input current and the input current reference signal of the power supply voltage waveform, the switching element is turned on and off to set the output voltage of the power factor improving means as the load voltage, while the AC power supply It is preferable to detect a zero cross and forcibly terminate the switching operation of the switching element after a predetermined time from the zero cross detection.

  The predetermined time is preferably changed according to the power supply frequency, the magnitude of the load, or the magnitude of the load voltage.

The predetermined time includes input current, power supply voltage, reactor inductance, current hysteresis width, or the number of times of switching as a parameter, time when switching of the switching element is in a permitted state, and an evaluation index related to harmonics It is preferable to set based on the relationship.
.

  The predetermined time is preferably set in consideration of the power factor.

  The predetermined time is preferably set in consideration of a switching loss accompanying the switching operation of the switching element.

  It is preferable to detect the output voltage when there is no load and the output voltage when there is a load, and control the voltage so that the ratio between the output voltage when there is no load and the output voltage when there is a load is a predetermined value.

  The AC power supply is preferably converted into a DC voltage by the rectifying means to be the load voltage, and a rectified average value or an effective value is preferably used instead of the output voltage at the time of no load and the output voltage at the time of the load. .

  The predetermined value is preferably a value obtained in advance according to the load state.

  As the predetermined value, it is preferable to use the ratio of the input voltage when there is a load and when there is no load.

  The AC power supply is preferably converted into a DC voltage by a rectifying means to be the load voltage, and a rectified average value or an effective value is preferably used instead of the input voltage.

  According to the present invention, switching of the switching element is started from the zero crossing of the AC power supply waveform and the switching is performed a predetermined number of times. The current control can be stabilized, and as a result, power harmonic regulation can be easily handled.

  In addition, by resetting the counter for counting the number of times of switching by detecting zero crossing, the current control is performed every half cycle of the AC power supply, and the current control is appropriately performed. Since the switching start time is changed according to the load and the magnitude of the input current, it contributes to the sine wave of the input current waveform by the current control.

  Further, since switching is performed within the power supply phase of 90 degrees, that is, the switching is prohibited including the vicinity of the peak region of the input current, it can contribute to the sine wave of the input current waveform as described above. Control can be stabilized. Further, since the number of times of switching is determined by various parameters, the sine wave of the input current waveform and the stabilization of the current control are optimally performed.

  Furthermore, in the case of a motor using an inverter means as a load for setting the number of times of switching, in addition to the above-described effects, it is particularly suitable for an inverter air conditioner and a refrigerator because its rotation speed and inverter frequency are the magnitude of the load. It is.

  In addition, since the number of times of switching and switching control are realized by software, the hardware cost of the power supply apparatus is not increased. Furthermore, since the number of times of switching is set to a value corresponding to the magnitude of the voltage of the AC power supply, it can be applied to household appliances in general and industrial equipment.

  In the power supply device of the present invention, when switching the switching means of the power factor improving means (boost chopper circuit) including the reactor, the switching is performed a predetermined number of times (at least a predetermined section within the power supply phase of 90 degrees) from the zero cross detection of the input current waveform. In other words, even if the input voltage or output voltage fluctuates or the load 4 fluctuates in the peak region of the input current (in the vicinity where the input voltage Vi becomes larger than the output voltage Vo), the input current control is performed so as not to switch. Stabilization and reduction of high-order harmonic current.

  Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 and 2, parts that may be considered the same as or the same as the components shown in FIGS. 23 and 24 are denoted by the same reference numerals, and redundant description is omitted. FIG. 3A corresponds to FIGS. 25A and 26A.

  In FIG. 1, this power supply apparatus detects an input current Ii of a boost chopper circuit 3 by a detection signal from a current sensor (for example, CT) 6 and an input voltage Vi of the boost chopper circuit 3. For detecting the output voltage Vo of the step-up chopper circuit 3, the detected value and the zero cross detection of the AC power supply by the power supply phase detection circuit 5. And a control unit 13 such as a microcomputer for outputting a signal for turning on / off the switching element 3c of the boosting chopper circuit 3 to the driving unit 7. Since the other parts are the same as those in FIG. 23, the description thereof is omitted.

  The operation of the power supply device having the above configuration will be described with reference to the current control block diagram of FIG. 2, the waveform diagram of FIG. 3, and the time chart diagram.

  The control unit 13 generates a signal (switching signal) for switching the switching element 3c based on the deviation between the output voltage command value (application voltage command value of the load 4) and the output voltage Vo. At this time, the zero cross point of the input power supply waveform is detected by the detection signal from the power supply phase detection circuit 10 to reset the pulse counter 13a. When the pulse counter 13a reaches a predetermined count value, the operation of the switching element 3c is performed. Is prohibited.

  As shown in FIG. 2, first, the deviation between the output voltage command value and the detected voltage Vo by the output voltage detector 12 is calculated by the calculating means 8a, and the current reference signal amplitude creating means 8b uses the calculated deviation to calculate the input current reference signal. An amplitude value (a so-called reference sinusoidal amplitude value) is created.

  The multiplication unit 8c multiplies the created amplitude value by the detection voltage Vi by the input voltage detection unit 11, and a hysteresis is created based on the input current reference signal of the multiplication result. As the detection voltage Vi, an input voltage waveform or an absolute value of the input voltage waveform may be used.

  The value of the input current reference signal having hysteresis and the detected input current Ii by the input current detector 10 are compared by the hysteresis comparator means 8d, and a switching signal of the switching element 3c is created based on the comparison result. The boost chopper circuit 3 is controlled by this switching signal, that is, the switching element 3c is switched using the reference current reference signal as a reference sine wave as in the conventional case, and an input current waveform is obtained (see FIG. 3A).

  On the other hand, the pulse counter 13a is reset by the reset signal of the detected power supply phase signal (zero cross) by the power supply phase detection circuit 5, and the output signal of this pulse counter 13a and the switching signal obtained by the hysteresis comparator 8d are logical product means (AND). Circuit) 8f performs a logical operation, and a switching signal as a result of the operation is output to the drive unit 7.

  As shown in FIG. 3, the pulse counter 13a counts the number of times of switching of the switching element 3c (see FIG. 3 (e)), but the output of the pulse counter 13a becomes H level when reset, and the count value Becomes L level when a predetermined value (pulse set value) set in advance is reached (see (f) in the figure). The predetermined value of the pulse counter 13a includes a section in the vicinity of the peak region of the input current Ii (Vi ≧ Vo). For example, the number of pulses corresponding to the power supply phase within 90 degrees is obtained empirically.

  In this case, when the zero cross is detected, the switching element 3c is turned on (see (b) and (c) in the figure), and then the input current Ii rises and reaches the upper limit value, so that the switching element 3c is turned off. (See (a) and (c) in the figure), the pulse counter 13a is incremented (see (d) and (e) in the figure). In this way, by turning on and off the switching element 3c, the input current Ii has a sine wave shape.

  As described above, in the vicinity where the input voltage Vi is larger than the output voltage Vo (near the peak region of the input current Ii), that is, in a region where the fluctuation of the input voltage Vi or the output voltage Vo, or the fluctuation of the load 4 is large, the switching element. The switching operation of 3c is prohibited.

  Therefore, up to near the peak area of the input current Ii, high-order harmonics are reduced by controlling the input current waveform as a sine wave by switching current control, switching is prohibited after the peak area, and the number of switching times per half cycle of the AC power supply is reduced. The current control can be stabilized by suppressing variations (assuming constant), and as a result, a countermeasure for clearing the power harmonic regulation can be easily achieved.

  The switching start time of the switching element 3c is the zero cross detection time, but may be a predetermined positive value (delay) or a negative value (early) with respect to the zero cross detection. In this case, the predetermined positive value or negative value is changed from the load 4 or the magnitude of the input current Ii. For example, the larger the value is, the faster the value is, and the smaller the value is, the more the value is delayed. preferable.

  The predetermined value may be changed based on the power supply frequency (for example, 50 Hz or 60 Hz), the magnitude of the input voltage or input current, the magnitude of the output voltage, the load, etc. It is preferable that the power supply device is applied in combination with the power supply device, or a combination thereof. Further, the power supply device may be used in a different manner depending on the use environment of the power supply device or the device using the power supply device.

  In other words, the harmonic characteristics of the power supply change depending on the input current, power supply frequency, etc., and the number of switching times is an important parameter in the harmonic suppression effect. This is because the harmonic suppression effect is improved. In addition, when there is a margin with respect to the power supply harmonic regulation value, reducing the number of times of switching has an effect of improving the efficiency in terms of switching loss and reactor loss.

  When changing the number of times of switching, for example, when the number of switching is set to 5 when the input current is 7 A or more, the number of switching is changed when the input current is 6 A or less. If the AC power supply is 50 Hz, it is changed to 8 times, and if the AC power supply is 60 Hz, it is changed to 7 times.

  As the load 4, a motor via inverter means is optimal as described in the conventional example. In this case, the switching start time and the predetermined value are preferably values determined according to the motor rotation speed or the inverter frequency. As described above, the input current waveform can be made closer to a sine wave, and the current control can be stabilized.

  Further, a detection means for detecting the input power supply voltage may be provided, and the predetermined value may be changed according to the magnitude of the input power supply voltage. By the way, the parameter for setting the above-mentioned predetermined value varies depending on the power supply environment and the equipment used.

  Therefore, if the switching control of the switching element 3c described above is configured by software, the world of PFC (controller) can be achieved by using, for example, the converter block diagram of FIG.

  In this case, a loop that does not require high-speed control such as voltage control is configured by software, and the current controller includes a hysteresis comparator 8d, a logic circuit 8f, a drive unit (gate drive circuit) 7 and a switching element (IGBT) shown in FIG. ) Represents a switching operation control unit by a power main circuit such as 3c.

  The software configuration 20 is realized by the microcomputer of the control unit 13. First, a deviation between the voltage command value 20 a and the output voltage detection value corresponding to the power supply environment and the equipment used is calculated by the computing means 20 b. Using this deviation, the proportional term P is calculated by PI (proportional integral) 20c of the voltage reference signal amplitude creating means 8b, and its integral term I is calculated. The proportional term P and the integral term I are used to calculate the current command amplitude value. Is calculated.

  The current command amplitude value is converted into an analog output signal by the D / A conversion means 20d and output to the multiplication means 7c. As described above, current control is performed based on the multiplication result by the multiplication means 7c.

  In this current control, a deviation between the current command value and the output current value is calculated by the calculation means 21, and this is input to the current controller 22 to perform the above-described operation. The software configuration 20 includes a pulse counter 13a and a switching operation controller 20e. The pulse counter 13a starts a count operation in response to a reset signal from the power supply phase detection circuit (zero cross) 5.

  The switching operation controller 20e determines whether or not the count value of the pulse counter 13a has reached a predetermined value determined by the parameters corresponding to the power supply environment and the equipment used, and monitors the count value. The switching permission signal (see FIG. 3F; H level) of the switching element 3c is output to the current controller 22 until the count value reaches a predetermined value.

  In the current controller 22, the switching element 3c is turned on / off so that the input current Ii falls within the range between the upper limit value and the lower limit value, and this switching frequency information is output to the pulse counter 13a.

  When the count value of the pulse counter 13a reaches a predetermined value, the switching operation controller 20e that monitors the count value sets the permission signal for inhibiting the switching of the switching element 3c to the L level. In response to the L level permission signal, the current controller 22 stops the on / off operation of the switching element 3c.

  On the other hand, the input current full wave obtained by the operation of the current controller 22 is fed back to the computing means 21 and converted into an output current by the function G24 of the system on which the power supply device is mounted. A load current due to disturbance is added to the output current by the computing means 25, and this is integrated by the integrating unit 26 to become an output voltage.

  The output voltage is made the power supply voltage of the load 4, noise is removed by the LPF 27 and fed back to the software configuration 20. This fed back output voltage is converted to the output voltage detection value of the calculation means 20b by the A / D conversion means 20f.

  In order to protect the power supply apparatus, the overvoltage / overcurrent protection means 23 outputs overvoltage / overcurrent protection information to the switching operation controller 20e and the current controller 22, and a known protection operation is performed.

  As described above, according to the software configuration 20, the switching control of the switching element 3c can be appropriately performed by using parameters according to various states, and the cost of the power supply device (hardware) does not increase. .

  In the third embodiment, portions common to the above embodiment are denoted by the same reference numerals and description thereof is omitted.

  As an example of the power factor improving and harmonic current suppressing means, there is the one described in the first embodiment or the second embodiment. This method stabilizes current control with a small number of switching times, and facilitates compliance with power supply harmonic regulations. Specifically, the input current waveform can be controlled to an arbitrary waveform by short-circuiting the power supply through the reactor using a boost chopper circuit as shown in FIG. 1, and a control structure as shown in FIG. Then, the switching element is turned on / off so that the input current waveform is in the shape of the power supply voltage waveform, and after the predetermined number of switching times is reached, the switching operation is prohibited to stabilize the input current (FIG. 3). (Refer to the waveform of).

  However, in this method, the input current waveform is easily affected by variations in components such as variations in the inductance value of the reactor and variations in hysteresis width (setting range of the upper limit value and lower limit value) due to resistance value variations. For example, in the case where the hysteresis width is narrow and the case where the hysteresis width is wide, if the output load voltage and the number of times of switching are the same, the current command value operates differently, so FIG. 5 (a) and FIG. 5 (b). As shown in FIG. Even when the reactor inductance is different, the current waveform is different. These waveform differences greatly affect the harmonic current, and in some cases may exceed the power supply harmonic regulation value.

  On the other hand, even if the current hysteresis width and the reactor inductance value are the same, if switching is performed in a situation where the power supply voltage is different, the slope of the current when the switching element is short-circuited and released differs, so that the current is different even in regions where the power supply voltage ratings are different. The waveform is different. Since it is necessary to suppress power supply harmonics in the range from 200-10% in Japan to 240V + 10% overseas in order to make the power supply compatible with the world where the fluctuation range of the power supply voltage must be seen largely, In the prior art, it has been difficult to cope with component variations.

  For power supply harmonics, the limit value is determined for each order for harmonic currents up to the 40th order in the IEC standard, and it is difficult to express them in a unified manner. Therefore, the harmonic evaluation index Ymax is described as follows. To do.

When the nth harmonic component of the input current is In and the limit value for the nth harmonic is Isn, the values normalized by the limit value are
I2 / Is2, I3 / Is3, I4 / Is4,..., In / Isn,..., I40 / Is40, which are values indicating the ratio to the limit value.
Among these, the value indicating the maximum is Ymax,
Ymax = max (I2 / Is2, I3 / Is3, I4 / Is4, ..., In / Isn, ..., I40 / Is40)
When Ymax> 1, it can be expressed as NG with respect to the standard, and when Ymax ≦ 1, it can be expressed as OK with respect to the standard.

  Here, as described above, the variation in the inductance value of the reactor, the component variation such as the variation in the hysteresis width (the upper limit value and the lower limit value setting range) due to the variation in the resistance value, and the difference in the power supply voltage are factors that cause Ymax> 1. It becomes. Therefore, conventionally, it has been difficult to satisfy the power supply harmonic regulation value.

  In the third embodiment, the power factor is improved with a small number of times of switching, and the object is to perform control corresponding to power supply harmonic regulations that are resistant to component variations and power supply fluctuations.

  Here, when the time width during which the switching permission signal shown in FIG. 3 is in the permitted state is Ton−, the input current, the power supply voltage, the reactor inductance, the current hysteresis width, and the switching frequency of the switching element 3c are used as parameters. It became clear that the characteristic of Ymax is as shown in FIG. As shown in the figure, when Ton is 2.75 to 3.1 ms, the result that Ymax ≦ 1 is obtained.

  However, the relationship between the input current and Ton is as shown in FIG. 8, and the reactor inductance is large and / or the current hysteresis width is large or / and the number of times of switching is large or / and the power supply voltage is small. In some cases, Ton increases and shifts toward (1) in the figure, while the reactor inductance is small or / and the current hysteresis width is small or / and the number of times of switching is small or / and the power supply voltage is In the prior art, it was difficult to set the value of Ton such that Ymax ≦ 1, such as when Ton is small and shifted toward the same direction (2).

  Therefore, in the present embodiment, the switching frequency of the switching element 3c is set so that Ton falls within a predetermined range in order to correspond to the world wide power supply voltage range even in a situation where there is a variation in the reactor inductance value and a variation in the current hysteresis width. Provide a power supply that automatically adjusts.

  When the ON width Ton of the switching permission signal shown in FIG. 3 is smaller than the first predetermined value (2.75) in FIG. 7, the power supply device of the present embodiment increases the number of times of switching of the switching element 3 c to increase the ON width. When Ton is larger than the second predetermined value (3.10), the switching frequency of the switching element 3c is decreased. When the ON width Ton of the switching permission signal is equal to or larger than the first predetermined value (2.75) and equal to or smaller than the second predetermined value (3.10), the switching frequency of the switching element 3c is kept as it is.

  Here, FIG. 7 is a diagram in which the values of the parameters shown in FIG. 6 are varied, Ymax at that time is measured, and Ymax values are plotted on the horizontal axis of Ton. Here, since NG with respect to the IEC standard under the condition of Ymax> 1, FIG. 7 changes the number of times of switching of the switching element 3c for any reactor and current hysteresis width within the range of FIG. Thus, if Ton is always controlled within a range in which Ymax ≦ 1 (upper limit is 3.05 ms to 3.10 ms, and lower limit is around 2.8 ms), the IEC standard is satisfied. .

  As a result, as shown in FIGS. 9 and 10, when the current hysteresis width is small, the switching frequency of the switching element 3c is set to 6 times, and when the current hysteresis width is large, the switching frequency is set to 5 times. In other words, this means that the number of times of switching is changed so that the instantaneous average value of the section in which the switching operation is performed becomes equal regardless of the hysteresis width of the current.

  That is, FIG. 7 shows the Ton-Ymax characteristics when these parameters are changed in consideration of variations in the inductance value of the reactor and component variations such as hysteresis width variation due to variation in resistance value. If the number of times of switching is changed according to the result of No. 7 and the Ton is always controlled to a range in which Ymax ≦ 1, the power supply harmonic regulation value is satisfied even if there is a variation in the parts.

  Furthermore, since the characteristics shown in FIG. 7 are those at a power supply frequency of 50 Hz, it can be applied even at 60 Hz by replacing the time axis of Ton with the power supply phase axis. As a result, it is possible to achieve a worldwide power supply, and it is possible to carry out control that complies with power harmonic regulations that are strong against power fluctuations (differences in power supply voltage) as well as component variations.

  Specifically, as shown in FIG. 11 and FIG. 3, the Ton upper limit / lower limit calculating means 102 is based on FIG. 7 and sets the value of the time Ton such that Ymax ≦ 1 (upper limit / lower limit). ) Is output. In this example, the upper limit value is set to 3.10 ms and the lower limit value is set to 2.75 ms. As will be described later, the upper limit value / lower limit value of the time Ton may be changed according to conditions such as the magnitude of the input current. In that case, the Ton upper limit value / lower limit value calculating means 102 Based on conditions such as size, the optimum upper limit value / lower limit value is calculated.

  The pulse counter 13a and the timer counter 101 are reset by a reset signal of the detected power supply phase signal (zero cross) by the power supply zero cross detecting means 5. As a result, the timer counter 101 starts measuring the time Ton. The pulse counter 13a counts the number of times of switching of the switching element 3c, and when the counter value reaches a predetermined value set in advance (pulse setting value, 5 times in this example), the output of the pulse counter 13a (see FIG. 3 (f)) becomes the L level, whereby the measurement of the time Ton by the timer counter 101 is stopped. For this reason, the timer counter 101 outputs the time Ton when the number of times of switching is five. In this example, it is assumed that the time Ton at this time is 2.70 ms, for example.

  On the other hand, the above-described upper limit / lower limit value (upper limit is 3.10 ms, lower limit is 2.75 ms) is output from the Ton upper limit / lower limit calculator 102 to the switching frequency calculator 103. The switching frequency calculation means 103 compares the time Ton with the upper limit value / lower limit value. Here, since the time Ton is below the lower limit value, the pulse set value set in the pulse counter 13a is increased by one. (6 times in this example). Thereby, from the next cycle (zero cross), the time Ton is increased by the amount corresponding to the pulse counter value being 6 times, and the time Ton is controlled to exceed the lower limit value.

  On the other hand, when the time Ton exceeds the upper limit value as a result of the comparison between the time Ton and the upper limit value / lower limit value in the switching number calculation means 103 contrary to the above example, it is set in the pulse counter 13a. Decrease the set pulse value by 1 (in this example, 4 times). Thus, from the next cycle (zero cross), the time Ton is shortened by the amount corresponding to the pulse counter value being four times, and the time Ton is controlled to be below the upper limit value.

  In this way, the switching number calculation means 103 compares the time Ton with the upper limit value / lower limit value, and increases or decreases the pulse set value set in the pulse counter 13a by 1 based on the comparison result. Thereafter, the time Ton falls within the range between the upper limit value and the lower limit value. Thereby, according to the result of FIG. 7, if it controls to the range where Ton always becomes Ymax <= 1, even if there exists said component dispersion | variation, a power supply harmonic regulation value can be satisfy | filled.

  As described above, the switching permission signal width Ton corresponding to the output of the pulse counter 13a detected by the timer counter 101, and the upper limit value calculated by the Ton upper limit value / lower limit value calculation means 102 (3.10 in FIG. 7). And the lower limit value (2.75 in the figure) are compared by the switching number calculation means 103, and the counter data of the pulse counter 13a is set based on the comparison result. The switching element 3c (see FIG. 1) performs switching for the specified number of times set in the pulse counter 13a.

  In the above, since the change in the number of switching causes a transient state in the input current waveform, it is desirable that the change period is set to about several seconds later than the power supply period, while the low-pass filter 104 is used to perform the filtering process for the time Ton. .

  Further, the upper limit value / lower limit value of the time Ton may be changed depending on the magnitude of the input current (the upper limit value is set to a value smaller than 3.05 ms to 3.10 ms, and the lower limit value is set to be larger than about 2.8 ms). The power factor can be maintained from a light load to a heavy load by changing according to the magnitude of the input current. For example, in the case of a light load, the switching loss can be reduced by setting the upper limit value to a value smaller than 3.05 ms to 3.10 ms, for example, 2.9 ms, and reducing the number of times of switching of the switching element 3c. it can. On the other hand, in the case of a heavy load, the power factor can be improved by setting the lower limit value to a value larger than about 2.8 ms, for example, 2.9 ms.

Next, Example 4 will be described with reference to FIGS.
The fourth embodiment is a combination of the invention according to the applicant's application (Japanese Patent Application No. 2004-6882) and the third embodiment. The following description will focus on the contents specific to Example 4 (contents of Japanese Patent Application No. 2004-6882) in the present application.

  In the above, it can be said that the output DC voltage Vo is an important parameter for the input current waveform and the harmonic current. Therefore, if there is variation in the output DC voltage Vo, it will affect the input current by the current control, that is, the harmonic current characteristics and the power factor improvement characteristics will differ depending on the device on which the power supply device is mounted. There arises a problem that the adaptability of the power supply device is lowered.

  In the above-described power supply device, it is useful to perform voltage feedback control by software of a microcomputer from the viewpoint of cost. For this purpose, a voltage dividing resistor that divides the output DC voltage Vo in order to detect the output DC voltage Vo. A circuit may be provided and the output of the voltage dividing resistor circuit may be A / D converted.

  However, an error occurs in the detection of the output DC voltage Vo due to variations in the resistance value of the voltage dividing resistor circuit and variations in the A / D converter reference voltage AVR necessary for A / D conversion (that is, from the original value). Since the output DC voltage Vo including this error is fed back, the output voltage varies.

  The variation of these components is about ± 4 to 6%. For example, when an output DC voltage Vo of about 300V is detected, there is an error of about ± 12 to 18V, and the fluctuation of the output DC voltage Vo is the current control. Is not stable, and there is also a problem with the stability of the harmonic characteristics such that the power harmonic regulation cannot be cleared.

  The variation also greatly affects the input current waveform. The input current waveform cannot be kept similar to the input voltage waveform due to a decrease in the power supply voltage due to an increase in the input current or an increase or decrease in the power supply voltage due to the influence of other system connection devices. Affects the stability of the current control.

  Therefore, in the fourth embodiment, the following configuration is adopted.

  The power supply device of this embodiment uses a voltage dividing resistor circuit, an LPF, and an A / D converter for detecting the output voltage Vo (t) of the boost chopper circuit when controlling the boost chopper circuit including at least the reactor. While detecting the no-load output voltage Vo (0), a voltage deviation Ve between A × Vo (0) obtained by multiplying the no-load output voltage Vo (0) by a predetermined ratio value and the loaded output voltage Vo (t). The voltage control according to the minute is added to the current control, and the voltage at the time of load is kept at a predetermined ratio with respect to the voltage at the time of no load, thereby causing variations in the voltage dividing resistor and the A / D converter reference voltage AVR. Regardless, the load output voltage is kept constant.

  That is, according to the present embodiment, the ratio Vo (t) / Vo (0) between the output voltage of the step-up chopper circuit and the no-load output voltage becomes a value that does not depend on variations in the voltage dividing resistor and the reference voltage AVR of the A / D converter. .

  Therefore, if the ratio value A (= Vo (t) / Vo (0)) is obtained by measuring with a predetermined circuit, the value can be used in any model regardless of variations. Therefore, by storing the ratio value A in a table or the like in advance, Vo (t) = AVo (0) can be obtained, and any device can correct it to a true value.

(Example 1)
This will be described in detail below with reference to FIGS. In FIG. 12, parts that may be considered the same as or the same as the components in FIG.

  In FIG. 12, this power supply device detects an input current Ii of the boost chopper circuit 3 by a detection signal from a current sensor (for example, CT) 6 and an input voltage Vi of the boost chopper circuit 3. Therefore, the voltage dividing resistor circuit 15 of the resistors R1 and R2 connected in series, the voltage dividing resistor circuit 16 of the resistors R3 and R4 connected in series to detect the output voltage (output DC voltage) Vo, and the LPF for noise removal ( A low-pass filter) 17 and the voltage passing through the LPF 17 are detected by A / D conversion, and the voltage is boosted based on the detected value and the zero cross detection of the AC power source 1 by the power source zero cross detector (power source phase detector) 5. And a control unit 14 such as a microcomputer for outputting a signal for turning on and off the switching element 3c of the chopper circuit 3 to the driving unit 7.

  As a modification, the same effect as an active filter can be obtained by inserting the boost choke coil (reactor) 3a and the switching element 3c shown in FIG. For example, the position may be changed as appropriate. Moreover, since the control part 14 is provided with the function similar to the control part 13 of FIG. 1, and it is the same as that of FIG. 1 about the other part, the description is abbreviate | omitted.

  Referring also to FIG. 13, the control unit 14 receives a voltage command 14 a for issuing a command value (ratio value) A for suppressing variations in the output voltage, and an output voltage Vo (t) passed through the LPF 13 as A A / D 14b detected by / D conversion, a determination means 14c for switching the A / D converted output voltage Vo (t) when there is no load, and an output voltage Vo ( 0) for storing no load voltage, multiplying means 14e for multiplying the output voltage Vo (0) at the time of no load by the ratio value A, and a voltage command value of the multiplication result and an output at the time of load. The calculation means 14f for calculating the voltage detection value Vo (t), the voltage controller 14g for calculating the correction amount of the input voltage detection value Vi (t) based on the calculation result, and the power supply zero-cross detection unit 5 Based on the detection signal Similarly on the switching element 3c and includes a switching operation controller 14h for generating an off timing.

  Then, the control unit 14 multiplies the input voltage detection value Vi (t) by the operation value obtained by the voltage controller 14g and the switching element 3c based on the switching timing by the switching operation controller 14h. And a current controller 14j for controlling the input current Ii in consideration of the multiplication result of the multiplication means 14i when outputting the switching signal. The switching operation controller 14h and the current controller 14j may have a block configuration shown in FIG.

  The operation of the power supply apparatus having the above configuration will be described with reference to the processing system block diagram of FIG. 13 and the flowcharts of FIGS. The control unit 14 switches the switching element 3c based on the output voltage command value (applied voltage command value of the load 4) to make the output voltage a predetermined value necessary for the load 4 as well as the conventional method. Make the waveform sinusoidal. In order to improve the input AC waveform and reduce the higher harmonic current, the switching element 3c is switched a predetermined number of times based on the zero cross point of the input power supply.

  Here, the processing of the software configuration of the present embodiment will be described. First, in the voltage command value calculation processing system, the output voltage Vo (0) at no load is obtained by switching the determination means 14c and stored in the no load voltage storage means 14d. The voltage command value Vo * (t) is obtained using this output voltage Vo (0). The determination unit 14c determines whether there is no load or a load depending on whether the load 4 is operating.

  The no-load output voltage may be detected by creating a no-load state for a predetermined period. In this detection, the no-load state may be determined by a no-load determination means described later, and the detected value may be stored and updated. In addition, the detection of the no-load output voltage is performed by setting a predetermined time from the power-on of the power supply device to the start of load activation as a no-load state at the predetermined time, or by using an interval timer at a predetermined time. It is preferable to perform the operation when the operation is stopped.

  Then, as shown in FIG. 14, the ratio value A is referred to from a table empirically obtained in advance, or is calculated based on the current output voltage Vo (output voltage Vo (t) under load) ( Step ST1). This ratio value A is multiplied by the output voltage Vo (0) obtained at no load to obtain a voltage command value Vo * (t) (= A × Vo (0)) (step ST2).

  The ratio value A is a value obtained in consideration of clearing of power supply harmonic regulations, and when the load 4 is a motor, a value obtained from a voltage value required by the motor control system according to the amount of the load. Yes, it does not matter whether it is obtained by table reference or calculation by function.

  In the A / D conversion processing system that performs A / D conversion when detecting the output voltage, the input voltage, etc., as shown in FIG. 15, the type of A / D conversion data (output voltage or input voltage) is determined (step). ST10). If the data type is output voltage, the A / D conversion result is filtered and substituted for Vo (t) (step ST11). Subsequently, the load state is determined (step ST12). If there is a load, the output voltage Vo (t) is left as it is. If there is no load, the output voltage Vo (t) is substituted for the initial value Vo (0) ( Step ST13).

  If the data type is an input voltage, the A / D conversion result is filtered and substituted into Vi (t) (step ST14). Subsequently, the load state is determined (step ST15). If there is a load, the input voltage Vi (t) is left as it is. If there is no load, the output voltage Vi (t) is substituted for the initial value Vi (0) ( Step ST16). For other data, processing corresponding to the data is executed (step ST17).

  In the output voltage control system that performs the voltage feedback control, as shown in FIG. 16, in the PI control, the voltage deviation value Ve between the voltage command value Vo * (t) and the output voltage detection value Vo (t) is calculated by the calculation means 14f. Calculate (step ST20). A proportional term P (= Kp × Ve) is obtained for the voltage deviation Ve, and an integral term I (= Ki × sigma Ve) is obtained, thereby obtaining a command amplitude D (= P + I) (steps ST21 to ST24). ) To obtain a current command value. Kp is an arbitrary proportional gain, and Ki is an arbitrary integral gain.

  The interval time of the processing system described above is basically based on the relationship of the interval time of the voltage command value calculation processing system ≧ the interval time of the output voltage control processing system ≧ the interval time of the A / D conversion processing system.

  By the above processing, the voltage controller 14g, when the voltage command value is Vo * (t), multiplies the multiplication means 14i by multiplying the multiplication value for correcting the input voltage Vi so that the output voltage Vo (t) becomes Vo * (t). Output to.

  According to this, the output voltage and the input voltage in the processing system are obtained using the resistors R1 and R2 of the same voltage dividing resistor circuit 15 and the A / D converter reference voltage AVR. The voltage deviation Ve between the voltage command value Vo * (t) (= A × Vo (0)) and the output voltage Vo (t) varies depending on the resistances R1 and R2 of the voltage dividing resistor circuit 15 and the A / D converter reference. This corresponds to the amount corresponding to the variation of the voltage AVR.

  Therefore, in the switching section of the switching element 3c determined by the switching operation control 14h, the current controller 14j performs current control, and the output voltage Vo ( The voltage control that makes t) constant is taken into consideration.

  As the current control taking the multiplication result into account, if the switching operation control 14h and the current control 14j are configured as shown in FIG. 24, the output voltage command value in the current control may be changed.

  As described above, there are variations in the voltage dividing resistors R1 and R2, variations in the A / D converter reference voltage AVR, and the like. Even if an error occurs in voltage detection in the current control, there is no influence due to the detection error due to the voltage control. The output voltage Vo (t) is kept constant, the current control is stabilized, the variation of the input current waveform by the device is suppressed, and the applicability of the power supply device is improved.

(Example 2)
Since the input current waveform also affects the input voltage Vi, the A / D conversion processing system may be executed by the routine shown in FIG. In the method of obtaining the voltage command value Vo * (t) in this example 2, the ratio of the output voltage multiplied by the ratio value A to the output voltage Vo (0) at the time of no load and the input voltage Vi at the time of load and no load It is obtained by multiplying Vi (t) / Vi (0) (steps ST30 and ST31).

  As a result, since fluctuations in the input voltage Vi are taken into account, even if the power supply voltage fluctuates, the current control can be further stabilized by keeping the input current waveform similar to the input voltage waveform. Further, according to the above-described first embodiment, the voltage command value Vo * (t) is set by the output voltage when there is no load. Therefore, the power supply voltage decreases due to the decrease in the power supply voltage due to the increase in the input current or the influence of other system connection devices. Regardless of the increase / decrease, the ratio between the input voltage peak value and the output voltage can be kept constant.

  In Example 1 described above, voltage control is performed using the no-load output voltage and the load output voltage, but means for detecting the rectified average value or effective value of the DC voltage rectified by the rectifier circuit 2 is used. And storage means for storing the rectified average value or effective value at no load, and instead of the no-load output voltage and the load output voltage, the rectified average value or effective value and detected rectified average value of the storage means Alternatively, an effective value may be used.

  In this embodiment, as shown in FIG. 18, the control (reference numeral 200) described as the third embodiment and the load voltage ratio control (reference numeral 300) described as the second embodiment with reference to FIG. 12 to FIG. Can be combined to stabilize the load voltage, and the converter system as a whole can exhibit robustness against component variations. At this time, as shown in the control block diagram of FIG. 18, the product cost can be suppressed by configuring the control requiring a relatively high speed with hardware and configuring the control that may be a slow processing system with software. The current controller 22 in the figure can be configured by a hysteresis comparator 8d shown in FIG. Further, the fourth embodiment can be easily combined with other embodiments.

Next, Example 5 will be described with reference to FIG.
In the fifth embodiment, only the lower limit value (2.75) of the time Ton is set in the Ton lower limit value calculation unit 102. In the fifth embodiment, the use of the pulse counter 13a is omitted.

  As shown in FIG. 19, the timer counter 101 is reset by a reset signal (zero cross timing in the figure) of the detected power phase signal (zero cross) by the power zero cross detector 5. As a result, the timer counter 101 starts measuring the time Ton. Immediately after the measured value by the timer counter 101 exceeds the lower limit (2.75), the switching permission signal is detected when the falling edge of the switching-off signal of the switching element 3c (IGBT falling edge in the figure) is detected. Is prohibited output.

  Thus, immediately after exceeding the lower limit value (2.75) of the time Ton, at the timing of the falling edge of the switching-off signal of the switching element 3c, the switching permission signal is set to the prohibited output, thereby reliably. The time Ton can be entered between the lower limit (2.75) and the upper limit (3.10) in FIG. That is, even if the upper limit value (3.10) is not set in advance, immediately after the lower limit value (2.75) is exceeded, the switching permission signal is set to the prohibited output, so that the time Ton becomes the upper limit value (3 .10) is not exceeded.

  According to the fifth embodiment, since it is not necessary to use the pulse counter 13a, it is possible to reduce hardware cost or reduce software load.

  Next, Example 6 will be described.

  Furthermore, in a simple converter device in which it is not necessary to stabilize the load voltage too much, the time Ton is not synchronized with the switching signal (IGBT gate drive signal in FIG. 19) and the upper limit value (3.10). The switching permission signal may be forcibly set as a prohibited output so that the switching permission signal falls between the threshold value and the lower limit (2.75). Even in this case, the instantaneous average values of the switching operation sections shown in FIGS. 9 and 10 can be made equal, the power supply harmonic characteristics can be stabilized, and the harmonic current can be suppressed.

  That is, in the fifth embodiment shown in FIG. 19, after the measured value by the timer counter 101 exceeds the lower limit value (2.75), the switching permission signal is prohibited from output after waiting for the falling timing of the IGBT gate drive signal. On the other hand, in the sixth embodiment, when the measured value by the timer counter 101 exceeds the lower limit (2.75), immediately (forcibly) without waiting for the falling timing of the IGBT gate drive signal. B) The switching permission signal is set as a prohibited output.

  In the sixth embodiment, the timing at which the switching permission signal is set to be prohibited is set to the time when the measured value by the timer counter 101 exceeds the lower limit value (2.75), but instead, the upper limit value (3.10) is set. Or a predetermined value between the lower limit value and the upper limit value.

  Next, Example 7 will be described.

Example 7 relates to how to determine the upper limit value / lower limit value.
When the number of times of switching is changed, the time Ton increases. For example, as shown in FIG. 21, when the number of switching is changed from n times to (n + 1) times in a state where the input current is I1, Ton increases by {T (n + 1) −T (n)}.

FIG. 22 is a diagram schematically showing the tendency of Ymax-Ton in FIG.
As shown in FIG. 22, assuming that the lower limit value and the upper limit value of Ton are T1 and T2, T1 is a value larger than 2.75 which is the first threshold value Tmin of Ymax <1, and T2 is Ymax < The value is smaller than 3.10 which is the second threshold value Tmax of 1. The width of T1 and T2 is set to be larger than the increment {T (n + 1) −T (n)} due to the change in the number of switching of Ton. Must.

  Ton when the number of switching is n is less than T1, and when Tn is increased by {T (n + 1) −T (n)} by changing the number of switching from n to (n + 1) times, it exceeds T2. In this case, Ton cannot be controlled to an appropriate value (between T1 and T2) by changing the number of switching times.

  Note that T1 and T2 must be set inside two threshold values Tmin and Tmax of Ymax <1 shown in FIG.

The eighth embodiment also relates to how to determine the upper limit value and the lower limit value.
In this converter device, the lower limit value = Tmin and the upper limit value = Tmax may be set. However, when the range between the lower limit value and the upper limit value is set wide, even if the number of times of switching is n times within this range, (n + 1) A situation occurs that satisfies multiple conditions of the number of times of switching, which may be the number of times. At this time, as shown in FIG. 14, T1 may be set to a value larger than Tmin, T2 may be set to a value smaller than Tmax, and the values for outputting the maximum power factor may be T1 and T2. . As a tendency, the larger Ton, the better the power factor, so T2 = Tmax and T1 = T2−ΔTon may be set. Here, ΔTon is the amount of Ton increase per switching. Since the maximum power factor point may vary depending on the input current value, the above T1 and T2 may be corrected.

The ninth embodiment is a modification of the eighth embodiment.
Since switching loss increases when the number of times of switching is increased, T1 and T2 may be set based on the maximum efficiency point instead of the maximum power factor point in the eighth embodiment.

  As described above, when the control range by T1 and T2 is set to be small in order to achieve the maximum power factor and maximum efficiency, the Ton for one switching is increased due to the influence of power supply voltage fluctuation and component variation. May not fall within the control range (T1 to T2). For example, when the number of times of switching is n and Ton <T1, switching is increased to (n + 1) times, and Ton> T2. In such a case, T1 or T2 may be changed to widen the Ton control range.

  7 and 22 which are Ton-Ymax characteristics are results at a certain output voltage. The results corresponding to FIGS. 7 and 22 vary based on the magnitude of the output voltage, more precisely based on the relationship between the input voltage and the output voltage. Therefore, the results corresponding to FIG. 7 and FIG. 22 are obtained in advance according to the magnitude of the output voltage, and T1 and T2 are corrected based on the magnitude of the output voltage with reference to those results. May be.

(Application circuit)
Since the above embodiment uses a boost chopper type power factor correction circuit, not only the representative circuit shown in FIG. 1, but also reactors as shown in FIGS. 20-1 to 20-4. It can be applied to all power supply short circuit via

  As described above, according to the above-described embodiment, it is possible to perform control corresponding to power supply harmonic regulations that is resistant to component variations and power supply fluctuations while improving the power factor with a small number of switching operations. In addition, it is possible to suppress power supply harmonics that are compatible with the world wide, and it is easy to globalize products equipped with this device.

  According to the present invention, the current control in the power supply device is stabilized, and the power supply harmonic regulation is easily supported. Therefore, the present invention is applicable not only to air conditioners and refrigerator compressors, but also to home appliances in general, and also to industrial equipment. Is possible.

The schematic block diagram which shows embodiment of the power supply device by this invention. The schematic block diagram which shows the control means contained in the said power supply device. The schematic waveform diagram and time chart for operation | movement description of the said control means. The schematic block diagram which shows the processing system in the said control means. The figure which shows the current waveform in case the current hysteresis width is narrow and wide in the power supply device. The figure which shows the parameter when the measurement of FIG. 7 is performed, and its fluctuation range. Ton-Ymax characteristic diagram. The figure which shows the relationship between an input electric current and Ton. The figure which showed the example of the frequency | count of switching in case the current hysteresis width is narrow in the said power supply device. The figure which showed the example of the frequency | count of switching in case the current hysteresis width is wide in the said power supply device. FIG. 9 is a block diagram illustrating a configuration example of a main part of a third embodiment. FIG. 9 is a block diagram illustrating a configuration example of a fourth embodiment. FIG. 10 is a block diagram of a processing system and the like of a control unit included in the power supply device according to the fourth embodiment. 9 is a schematic flowchart for explaining the operation of the power supply device according to the fourth embodiment. 12 is a schematic flowchart for explaining another operation of the power supply device according to the fourth embodiment. 10 is a schematic flowchart for explaining still another operation of the power supply device according to the fourth embodiment. The flowchart for demonstrating the modification of the process shown in FIG. FIG. 9 is a block diagram illustrating a configuration example of a fourth embodiment. FIG. 6 is a time chart for explaining the fifth embodiment. FIG. 10 is a diagram for explaining Example 12; FIG. 20 is another diagram for explaining the twelfth embodiment. FIG. 14 is still another diagram for explaining the twelfth embodiment. FIG. 14 is still another diagram for explaining the twelfth embodiment. FIG. 10 is a diagram for explaining Example 7; The figure which showed FIG. 7 typically. The schematic circuit diagram which shows the conventional power supply device. The schematic block diagram which shows the control means contained in the said conventional power supply device. The schematic waveform diagram explaining operation | movement of the said conventional power supply device. The other schematic waveform diagram explaining operation | movement of the said conventional power supply device.

Explanation of symbols

1 Input power supply (AC power supply)
2 rectifier circuit 3 boost chopper circuit 3a boost choke coil 3b reverse blocking diode 3c switching element 3d smoothing capacitor 4 load 5 power supply phase detection circuit 6 current sensor 7 drive unit 13 control unit 10 input current detection unit 11 input voltage detection unit 12 output voltage Detector 13a Pulse counter Ii Input current Vi Input voltage Vo Output voltage

Claims (18)

When converting the AC power supply into a DC voltage to be a load voltage, the AC power supply is short-circuited through the reactor to improve the power factor.
While switching the switching element of the power factor improving means including the reactor, the output voltage of the power factor improving means is turned on and off according to the comparison result of the input current and the input current reference signal of the power supply voltage waveform. Is a load voltage, and a zero cross of the AC power supply is detected, and the switching element is switched a predetermined number of times based on the zero cross detection.   The power supply device according to claim 1, wherein a switching start time of the switching element is changed according to a load of the power supply device or a magnitude of an input current.   The power supply device according to claim 1 or 2, wherein the switching frequency of the switching element is set so that a power supply phase of the AC power supply is within 90 degrees.   4. The power supply apparatus according to claim 3, wherein the number of switching times of the switching element is determined based on at least a load of the power supply apparatus, a magnitude of an input current, or a power supply frequency, or a combination thereof.   5. When setting the number of times of switching, when the load of the power supply device is a motor via an inverter means, it is obtained based on the motor rotation speed or the inverter output frequency. The power supply device according to item.   The power supply apparatus according to any one of claims 1 to 5, further comprising voltage detection means for detecting a voltage of the AC power supply, wherein the number of times of switching of the switching element is determined by the detected voltage.   The power supply device according to any one of claims 1 to 6, wherein the switching operation of the switching element is completed in a predetermined period after the zero-cross detection.   The power supply device according to claim 7, wherein the switching frequency of the switching element is adjusted so that the switching operation of the switching element is completed in the predetermined period.   9. The switching element according to claim 8, wherein when the switching operation of the switching element is performed after the predetermined time, the switching operation is performed by subtracting the switching frequency by a predetermined number of times from the previous switching frequency. Power supply.   10. The switching operation of the switching element is performed by increasing the switching frequency by a predetermined number of times from the previous switching frequency when the switching operation of the switching element is completed before the predetermined time. The power supply device described in 1.   11. The power supply according to claim 8, further comprising means for correcting the predetermined time when the switching operation of the switching element is not completed in the predetermined time as a result of changing the number of times of switching of the switching element. apparatus.   12. The power supply device according to claim 1, wherein the switching frequency of the switching element is counted by a counter function, and the count function is reset by the zero cross detection.   When the AC voltage is converted into a DC voltage to obtain a load voltage, the AC power supply is short-circuited through the reactor to improve the power factor, and the switching element of the power factor improving means including the reactor is switched. From the comparison result between the input current and the input current reference signal of the power supply voltage waveform, the switching element is turned on and off, and the output voltage of the power factor improving means is used as the load voltage, while the zero cross of the AC power supply is detected. A power supply device characterized in that after a predetermined time has elapsed since the zero cross detection, the switching operation of the switching element is completed by the next switching off signal of the switching element.   When the AC voltage is converted into a DC voltage to obtain a load voltage, the AC power supply is short-circuited through the reactor to improve the power factor, and the switching element of the power factor improving means including the reactor is switched. From the comparison result between the input current and the input current reference signal of the power supply voltage waveform, the switching element is turned on and off to set the output voltage of the power factor improving means as the load voltage, while detecting the zero crossing of the AC power supply. A power supply apparatus forcibly terminating the switching operation of the switching element after a predetermined time from the zero cross detection.   The power supply apparatus according to any one of claims 7 to 11, 13, and 14, wherein the predetermined time is changed according to a power supply frequency, a load size, or a load voltage.   The predetermined time includes input current, power supply voltage, reactor inductance, current hysteresis width, or the number of times of switching as a parameter, time when switching of the switching element is in a permitted state, and an evaluation index related to harmonics The power supply device according to any one of claims 7 to 11 and 13 to 15, wherein the power supply device is set based on the relationship.   An output voltage when there is no load and an output voltage when there is a load are detected, and voltage control is performed so that a ratio between the output voltage when there is no load and the output voltage when there is a load is a predetermined value. Item 17. The power supply device according to any one of Items 7 to 16. The AC power supply is converted into a DC voltage by the rectifying means to be the load voltage,
18. The power supply device according to claim 17, wherein a rectified average value or an effective value is used in place of the no-load output voltage and the load-loaded output voltage.

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