CN201197117Y

CN201197117Y - Frequency conversion type voltage regulating circuit

Info

Publication number: CN201197117Y
Application number: CNU2008200099750U
Authority: CN
Inventors: 张裕渊; 王奕桦
Original assignee: Zippy Technology Corp
Current assignee: Zippy Technology Corp
Priority date: 2008-04-29
Filing date: 2008-04-29
Publication date: 2009-02-18
Anticipated expiration: 2018-04-29

Abstract

A frequency conversion type voltage regulating circuit is used for a power supply with a boosting unit and a power conversion unit, wherein the boosting unit modulates input power to be converted into boosting power, the boosting control circuit is also connected with the frequency conversion type voltage regulating circuit, the frequency conversion type voltage regulating circuit comprises a voltage detecting circuit and a frequency setting circuit, the voltage detecting circuit detects the input power transmitted to the boosting unit and generates an input level signal according to the magnitude of the input power, the frequency setting circuit generates a corresponding reference frequency signal according to the input level signal and adjusts the frequency of the power converted by the boosting unit according to the reference frequency signal; the circuit architecture judges the level of the input power, and the booster unit works at different frequencies according to the level of the input power, so that the beneficial effects of reducing the working load of the conventional booster unit, reducing the switching loss and reducing harmonic waves and noise are achieved.

Description

The frequency conversion type regulating circuit

Technical field

The utility model relates to a kind of frequency conversion type regulating circuit, is a kind of circuit of importing the input electric power of a power supply unit by converter technique and switching voltage-regulating technique with adjustment.

Background technology

As shown in Figure 1, most power supply unit (transducer that comprises AC/DC or DC/DC) all comprises filtering and rectification unit 1, the power conversion unit 3 of one boosting unit 2 (comprise known power factor correction function unit and also have the effect of boosting) and a suitching type, this power supply unit is obtained an input electric power 8 by this filtering and rectification unit 1 after connecting a power source, (the same via this boosting unit 2 again, also comprise known power factor correction function unit) adjust the voltage of this input electric power 8 and form the electric power that boosts, and is that an output power 9 drives at least one load via this power conversion unit 3 with this power conversions of boosting, wherein this boosting unit 2 comprises a charging and discharging circuit, one switch element and one produces the boost control circuit of this switch element conducting of a drive, this boost control circuit is adjusted the empty accounting (duty ratio) of this drive signal, that is the turn-on cycle width of controlling this drive signal to be to adjust the ON time of this switch element, further controls the voltage of this charging and discharging circuit and reaches this input electric power 8 boosted and form the purpose of this electric power that boosts; Above-mentioned boosting unit 2 is except the empty accounting (dutyratio) of adjusting this drive signal, known boosting unit 2 also is divided into continuous current pattern (Continuous Current Mode, CCM) with discontinuous current-mode (Discintinuous Current Mode, DCM) two kinds, discontinuous current-mode major part now only is used for low power power supply unit, and power supply unit is controlled to be main flow with the continuous current pattern now, wherein, because of this continuous current pattern that limits of its operation principle is all and decides frequency formula control, that is this boosting unit 2 this switch element of drive of utilizing fixed frequency to be controlling the current cycle of this charging and discharging circuit, and the empty accounting of its drive signal (duty ratio) is subjected to the influence of load height; Yet, above-mentioned boosting unit 2 (comprising known power factor correction function unit) provides the electric power that boosts of deciding voltage for reaching, the turn-on cycle of its switch element must very significantly change with input current, for example importing electric power 8 has height and floats between may be from 90V to 150V when fluctuating, and this boosting unit 2 is in order to provide the electric power that boosts of 380V, must make the turn-on cycle of this switch element significantly prolong so that the voltage liter of 290V to be provided, therefore make this switch element bear sizable electric current, and under high pressure the handoff loss of Chan Shenging (switching loss) is very big, relatedly make the influence of harmonic wave and noise (NOISE) very obvious, remain to be improved.

The utility model content

When working in the continuous current pattern in view of known booster circuit, need significantly adjust the turn-on cycle of switch element in this booster circuit because of fixed-frequency, and produce tangible handoff loss, harmonic wave and noise, and this switch element need bear bigger electric current, causes the problem that cost improves or the life-span reduces.

The utility model is a kind of frequency conversion type regulating circuit, be used in power supply unit with a boosting unit and a power conversion unit, and this power supply unit connects an input source to obtain an input electric power, wherein comprise a boost control circuit in this boosting unit and a continuous current pattern is provided, this boost control circuit obtain a reference frequency with this input electric power of modulation to be converted to the electric power that boosts, and this boost control circuit also connects a frequency conversion type regulating circuit, this frequency conversion type regulating circuit comprises a voltage detection circuit and a frequency setting circuit, wherein this voltage detection circuit detecting is sent to the input electric power of this boosting unit, and produce an input position calibration signal according to the size of this input electric power, this frequency setting circuit then produces a corresponding reference frequency signal according to this input position calibration signal, and transmit this reference frequency signal to this boost control circuit to adjust the frequency of this boosting unit power conversion; Judge the height of this input electric power by above-mentioned circuit framework, and make this boosting unit import the height of electric power and to work in different frequencies according to this, change by operating frequency can make this boosting unit reach the effect that this input electric power is boosted to the certain bits standard with lower handoff loss, and lower frequency is also being represented and can be in the identical time had long turn-on cycle with less switching times, thereby can reduce the operating load of this boosting unit and reduce handoff loss and harmonic wave, generating noise.

In sum, the beneficial effect that the utility model reached is as follows:

1. can reduce the operating load of this boosting unit.

2. reduce handoff loss and harmonic wave, generating noise.

Description of drawings

Fig. 1 is a known power source supply framework calcspar.

Fig. 2 is the framework calcspar of the utility model one embodiment.

Fig. 3 is the framework calcspar of the utility model preferred embodiment.

Fig. 4 is the frequency curve chart () of the utility model and known technology.

Fig. 5 is the frequency curve chart (two) of the utility model and known technology.

Embodiment

Relevant detailed description of the present utility model and technology contents now cooperate schematic view illustrating as follows:

See also Fig. 2, wherein this power supply unit has filtering and rectification unit 1, one boosting unit 2 and a power conversion unit 3, this filtering is connected an input source and obtains an input electric power 8 with rectification unit 1, this input electric power 8 is delivered to this boosting unit 2 after filtering and rectification, this boosting unit 2 comprises a boost control circuit 21, by an energy storage inductor 22, the charging and discharging circuit that one diode 24 and a storage capacitor 25 are constituted, an and switch element 23 that is connected in this charging and discharging circuit, this boosting unit 2 provides a continuous current pattern (Continuous Current Mode, CCM) modulation should be imported electric power 8, this charging and discharging circuit obtains this input electric power 8 chargings, this boost control circuit 21 produces a pulse wave signal to control the turn-on cycle of this switch element 23 according to a reference frequency, thereby further control the sequential that discharges and recharges of 8 pairs of these charging and discharging circuit of this input electric power, thereby should import electric power 8 and be converted to the electric power that boosts and deliver to this power conversion unit 3, is that an output power 9 is to drive load by this power conversion unit 3 with this power conversions of boosting, this boost control circuit 21 can be obtained a feedback signal from this power conversion unit 3, and adjusts the empty accounting (duty ratio) of this pulse wave signal according to this feedback signal; Yet, this boost control circuit 21 also connects a frequency conversion type regulating circuit 4, this frequency conversion type regulating circuit 4 comprises a voltage detection circuit 41 and a frequency setting circuit 42, wherein these voltage detection circuit 41 detectings are sent to the input electric power 8 of this boosting unit 2, and produce an input position calibration signal according to the size of this input

electric power

8,42 of this frequency setting circuits produce a corresponding reference frequency signal according to this input position calibration signal, and transmit this reference frequency signal to this boost control circuit 21 to adjust the frequency of these boosting unit 2 power conversions; The input position calibration signal that above-mentioned voltage detection circuit 41 produces can be imported the proportional linearity change of electric power 8 with this, and after this frequency setting circuit 42 obtains this input position calibration signal, the linearity change that can make reference frequency that this reference frequency signal provides and this input position calibration signal be inverse ratio, as shown in Figure 4, Fig. 4 is the curve chart of this input electric power 8 with these boosting unit 2 operating frequencies, the frequency curve 71 that wherein comprises a given frequency curve 70 and a modulation, known boosting unit 2 is with continuous current pattern (Continuous Current Mode, this given frequency curve 70 is a straight line (frequently fixed) when CCM) working, the electric power that boosts that empty accounting (duty ratio) that only utilize to adjust this pulse wave signal is kept behind the modulation has fixed voltage, the frequency curve 71 of reviewing this modulation is the straight line that is inversely proportional to this input electric power 8, when therefore the voltage of this input electric power 8 is higher, this frequency setting circuit 42 can produce the lower reference frequency signal of frequency, make this boosting unit 2 with lower frequency work, to reduce switch cost and harmonic wave, noise, and the operating load that reduces this boosting unit 2.

Another embodiment of foregoing circuit framework also can make this voltage detection circuit 41 set a fiducial value and compare with this input electric power 8, on behalf of this input electric power 8, make this input position calibration signal have be higher than a high levle of this fiducial value, and represent this input electric power 8 to be lower than a low level of this fiducial value, and this frequency setting circuit 42 is set this reference frequency signal and can be tuned as a different first frequency or a second frequency, this reference frequency signal was tuned as this first frequency when wherein this input position calibration signal was high levle, this reference frequency signal was tuned as this second frequency when this input position calibration signal was low level, thereby make this frequency conversion type regulating circuit 4 can provide this boosting unit 2 two different reference frequencies, and above-mentioned first frequency is lower than this second frequency, to make the frequency work that this boosting unit 2 can be lower when these input electric power 8 voltages are higher; And the voltage detection circuit 41 of above-mentioned another embodiment also connects a hysteresis circuit 43 and adjusts this fiducial value (as shown in Figure 3) to produce a buffer voltagc, wherein this buffer voltagc is turned down this fiducial value according to the reverse buffer voltagc of high levle triggering for generating of this input position calibration signal, and this fiducial value is heightened according to the low level triggering for generating forward buffer voltagc of this input position calibration signal, so can after sending the input position calibration signal of high levle, this voltage detection circuit 41 make this fiducial value descend, to avoid this input electric power 8 floating and frequency is beated fast slightly, in like manner, this hysteresis circuit 43 makes this fiducial value rise send the input position calibration signal of low level in this voltage detection circuit 41 after, also has identical effect; This input electric power 8 sees also Fig. 5 with the curve chart of these boosting unit 2 operating frequencies in the foregoing description, also visible this given frequency curve 70 among this figure, the frequency curve 72 of this modulation then is divided into a lower first frequency and a higher second frequency, when wherein the voltage of this input electric power 8 is higher than the fiducial value of setting then the frequency curve 72 of this modulation drop to about 65KHz, when these input electric power 8 voltages are lower than the fiducial value of setting then the frequency curve 72 of this modulation rise to 130KHz, thereby reach above-mentioned minimizing switch cost and harmonic wave, noise, and the beneficial functional that reduces these boosting unit 2 operating loads.

Though the utility model discloses as above with preferred embodiment; right its is not in order to limit the utility model; any those skilled in the art; in not breaking away from spirit and scope of the present utility model; and a little change and the retouching done; all should be covered by in the utility model, therefore protection range of the present utility model is as the criterion when looking the claim person of defining.

Claims

1. A frequency conversion voltage regulation circuit, used for a power supply with a boost unit (2) and a power conversion unit (3), and the power supply is connected to an input source to obtain an input power (8 ), wherein the boost unit (2) includes a boost control circuit (21) and provides a continuous current mode, and the boost control circuit (21) modulates the input power (8) according to a reference frequency ) to be converted into a boosted power, and the boost control circuit (21) is also connected to a frequency conversion voltage regulation circuit (4), characterized in that the frequency conversion voltage regulation circuit (4) includes:

A voltage detection circuit (41), which detects the input power (8) sent to the boost unit (2), and generates an input level signal according to the magnitude of the input power (8);

A frequency setting circuit (42), which generates a corresponding reference frequency signal according to the input level signal, and transmits the reference frequency signal to the boost control circuit (21) to adjust the boost unit ( 2) Convert the frequency of the electric power.

2. The frequency conversion voltage regulating circuit according to claim 1, characterized in that, the voltage detection circuit (41) sets a reference value to compare with the input power (8), so that the input level The signal has a high level indicating that the input power (8) is higher than the reference value, and a low level indicating that the input power (8) is lower than the reference value.

3. The frequency conversion voltage regulating circuit according to claim 2, characterized in that, the frequency setting circuit (42) sets the reference frequency signal to be adjustable to a different first frequency or a second frequency frequency, wherein the reference frequency signal is modulated to the first frequency when the input level signal is a high level, and the reference frequency signal is modulated to the first frequency when the input level signal is a low level Second frequency.

4. The frequency conversion voltage regulating circuit according to claim 3, wherein the first frequency is lower than the second frequency.

5. The frequency conversion voltage regulating circuit according to claim 2, characterized in that, the voltage detection circuit (41) is also connected to a hysteresis circuit (43) to generate a buffer voltage to adjust the reference value, wherein the The buffer voltage is triggered according to the high level of the input level signal to generate a reverse buffer voltage to lower the reference value, and is triggered according to the low level of the input level signal to generate a forward buffer voltage to lower the reference value. The value is adjusted up.

6. The frequency conversion voltage regulating circuit according to claim 1, characterized in that the input level signal generated by the voltage detection circuit (41) changes linearly in direct proportion to the input power (8).

7. The frequency conversion voltage regulating circuit according to claim 1, characterized in that, the frequency setting circuit (42) makes the reference frequency provided by the reference frequency signal linearly vary inversely proportional to the input level signal .

8. The frequency conversion voltage regulating circuit according to claim 1, characterized in that, the boost unit (2) includes a charging and discharging circuit for charging the input power (8), a charging and discharging circuit connected to the charging and discharging circuit The switch element (23) of the loop and the boost control circuit (21), the boost control circuit (21) generates a pulse signal according to the reference frequency to control the conduction period of the switch element (23) , controlling the charge and discharge sequence of the charge and discharge circuit by the input power (8) through the conduction period of the switch element (23).

9. The frequency conversion voltage regulation circuit according to claim 8, characterized in that, the boost control circuit (21) obtains a feedback signal from the power conversion unit (3), and adjusts the voltage according to the feedback signal. The duty cycle of the pulse wave signal.