CN2671223Y - Laser impulse power supply without main transformer - Google Patents

Abstract

The utility model discloses a transformerless laser pulse power supply. It includes a rectifier diode (4) and an energy storage capacitor (6) electrically connected to the AC power supply (1), especially the positive terminal of the rectifier diode (4) and one end of the energy storage capacitor (6), and the AC power supply (1) One end of the rectifying diode (4) is electrically connected to the other end of the AC power supply (1) via the capacitor (3), and the negative end of the rectifying diode (4) is connected in series with the other end of the energy storage capacitor (6). A silicon controlled rectifier (5) is connected, a pulse trigger (2) is connected across the two ends of the AC power supply (1), and the output terminal of the pulse trigger (2) is electrically connected with the gate of the silicon controlled rectifier (5). So that the thyristor (5) is turned on when the AC power supply (1) has a maximum value in the negative half cycle. It has the advantages of simple structure, small size and strong impact resistance. The charging voltage of the energy storage capacitor can be adjusted between 0 and 2× times of the AC power supply voltage; it can be used as a solid-state laser pulse power supply.

Description

No main transformer laser pulse power supply

Technical field The utility model relates to a pulse power supply, especially a transformerless laser pulse power supply.

Background Art At present, people often use pulse trigger power supplies in various forms of solid-state lasers, such as commercially available ones, which are mainly composed of electrically connected transformers, rectifier diodes, inductors, and energy storage capacitors. When working, the transformer is used to boost the 50Hz power frequency AC voltage and achieve isolation from the power grid. The rectifier diode converts the AC high voltage into DC, and then sends it to the energy storage capacitor after the current is limited by the inductor. However, this pulse-triggered power supply has the disadvantages of bulky, expensive, and low-efficiency power frequency transformers during high-power output. In order to solve this problem, there is a technical solution to use the three-phase grid voltage to be directly rectified by the bridge and then resonantly charged, but the upper limit of the discharge voltage is strictly limited, that is, it is only about 900V; The silicon-controlled silicon directly controls the phase voltage of the grid voltage, and then uses the voltage doubler rectification method to increase the phase-modulated voltage to make it reach the upper limit of the charging voltage. However, this scheme has a greater impact and interference on the grid. Moreover, the discharge frequency of the energy storage capacitor must be synchronized with the 50Hz frequency of the power grid, making it difficult to replace the existing trigger power supply.

Summary of the invention The technical problem to be solved by this utility model is to overcome the deficiencies in the prior art and provide a transformerless laser pulse power supply with simple structure, practicality and easy use.

The adopted technical scheme comprises a rectifier diode and an energy storage capacitor electrically connected to an AC power supply, particularly the positive end of the rectifier diode is electrically connected to one end of the energy storage capacitor and one end of the AC power supply, and the rectifier The negative end of the diode is electrically connected to the other end of the AC power supply via a capacitor, and a silicon controlled rectifier is connected in series between the negative end of the rectifier diode and the other end of the energy storage capacitor. A pulse trigger is connected, and the output terminal of the pulse trigger is electrically connected with the gate electrode of the silicon controlled rectifier, so that the silicon controlled rectifier is turned on when the alternating current power supply is at the maximum value in the negative half cycle.

As a further improvement of the technical solution, the pulse trigger is composed of an alternating voltage sampling part, a frequency division part and a time delay part which are electrically connected in series in sequence, and the said alternating voltage sampling part consists of a voltage divider and a half-wave shaping Circuit composition, wherein, the two ends of the voltage divider composed of resistors R1 and R2 connected in series are connected across the AC power supply, so as to obtain the alternating voltage signal of the AC power supply at the junction of the resistors R1 and R2, and the diode D1, Resistor R3 and the base of transistor BG1 are connected in series to form a half-wave shaping circuit, which is used to convert the alternating voltage signal output by the voltage divider into a rectangular wave signal. The frequency division component is a CD4520 integrated block. The input terminal pin ① of the block is connected to the output terminal of the alternating voltage sampling component, pins ③～⑥ are the output terminals, pin  is connected to VCC, and pin ⑧ is grounded, which is used to set the charging frequency relative to the frequency of the AC power supply. The components are composed of CD4538 integrated block, variable resistor RW1, and capacitor C1. Among them, the input pin ④ of the CD4538 integrated block is connected to the output end of the frequency division component, pin ⑩ is the output end, and the capacitor C1 is connected in series between pin ① and VCC. Variable resistor RW1, pin ② is connected to the contact point of capacitor C1 and variable resistor RW1, pin  is connected to VCC, and pin ⑧ is grounded, which is used to determine the delay time relative to the zero-crossing of the AC power output, and at this delay time When it arrives, the output width is greater than the trigger pulse between zero and the half cycle of the AC power supply; the input terminal pin ① of the CD4520 integrated block of the frequency division component and the output terminal of the alternating voltage sampling component are connected in series by a triode BG2 and the amplifier formed by resistor R5; the output terminal pin 10 of the CD4538 integrated block of the delay component is connected to the amplifier; the contact between the capacitor and the negative end of the rectifier diode and the silicon controlled rectifier is connected in series with a turn-off switch, A charging voltage controller is connected across the two ends of the energy storage capacitor, and the output terminal of the charging voltage controller is connected to the control terminal of the switch that can be turned off; the switch that can be turned off is a high-power MOSFET tube; the The charging voltage controller is that the input terminal of the comparison circuit is electrically connected with the sampling circuit and the voltage setter, and the output terminal is connected in series with an amplifier circuit and an isolation circuit. The input terminal of the sampling circuit is connected across the two ends of the energy storage capacitor, so It is said that the output terminal of the isolation circuit is electrically connected with the control terminal of the turn-off switch.

Compared with the prior art, the beneficial effects are as follows: firstly, since the alternating fluctuations of the AC power supply are used as a charging power supply with a monotonous and continuous rising voltage, the energy of the AC power supply is directly injected into the energy storage capacitor, so its Similar to a charging module with continuous and linear voltage rise, it saves the bulky transformer, making it simple in structure, small in size, low in manufacturing cost, practical, and has the characteristics of strong impact resistance, especially suitable for xenon lamp pulse discharge of solid-state lasers ; Second, by controlling the turn-off time of the switch that can be turned off, the charging voltage of the energy storage capacitor can be effectively and accurately controlled, so that it can be controlled at the AC power voltage It can be adjusted arbitrarily between multiples. If the AC power supply is 220V or 380V, the charging peak voltage can reach 620V or 1074V, which is enough to meet the demand of quite a lot of YAG pulsed lasers for excitation power. At the same time, the charging error and voltage fluctuation are very small. Small, after grouping and measuring the set 7 charging voltage values, each group is measured 10 times, the result is: the charging error as the difference between the set voltage and the actual charging voltage average value is only -0.3 ~ 0.3v, according to The fluctuation of the charging voltage calculated by the variance of each group of data statistics is only 0.77 ~ 1.35V; third, there is no impact and interference on the power supply grid, and the charging frequency of the energy storage capacitor can be adjusted arbitrarily within the frequency of the AC power supply .

BRIEF DESCRIPTION OF THE DRAWINGS The preferred mode of the present utility model will be further described in detail below in conjunction with the accompanying drawings.

Fig. 1 is a kind of embodiment circuit structure diagram of the utility model;

Fig. 2 is the circuit principle diagram of the pulse trigger among Fig. 1;

Fig. 3 is the time sequence diagram of the charging trigger pulse of the present invention, wherein, the figure a is the alternating voltage waveform of the AC power supply, the figure b is the waveform after sampling and shaping by the alternating voltage sampling part in the pulse trigger, and the figure c is the waveform through the pulse The waveform after frequency division by the frequency division component in the trigger, the charging frequency here is selected as 12.5Hz, the figure d is the waveform after the delay by the delay component in the pulse trigger, and the figure e is the charging waveform of the energy storage capacitor ; The ordinate in the figure is voltage, and the abscissa is time.

DETAILED DESCRIPTION Referring to Fig. 1, one end of AC power source 1, pulse trigger 2, and energy storage capacitor 6 are all electrically connected to the positive end of rectifier diode 4, and the other end of AC power source 1 and pulse trigger 2 is connected to rectifier diode through capacitor 3 The negative end of rectifier diode 4 is electrically connected to the negative end of the rectifier diode 4 and the other end of the energy storage capacitor 6 is sequentially connected in series with a turn-off switch 7 and a thyristor 5, and the two ends of the energy storage capacitor 6 are connected across a charge voltage control 8; wherein, the gate of the thyristor 5 is electrically connected to the output terminal of the pulse trigger 2, and the output terminal of the charging voltage controller 8 is connected to the control terminal of the switch 7 which can be turned off. The aforementioned turn-off switch 7 selects a high-power MOSFET tube; the charging voltage controller 8 is electrically connected to the sampling circuit and the voltage setting device for the input terminal of the comparison circuit, and the output terminal is connected in series with an amplifier circuit and an isolation circuit, wherein the sampling circuit The input end of the isolation circuit is connected across the two ends of the energy storage capacitor 6, and the output end of the isolation circuit is electrically connected with the control end of the switch 7 which can be turned off.

Referring to FIG. 2 , the pulse trigger 2 is composed of an alternating voltage sampling component 21 , a frequency dividing component 22 , and a delay component 23 , etc., which are electrically connected in series in sequence. one of them:

The alternating voltage sampling part 21 is composed of a voltage divider and a half-wave shaping circuit; wherein, the two ends of the voltage divider composed of resistors R1 and R2 connected in series are connected across the AC power supply 1, and the diode D1 and resistor R3 It is connected in series with the base of the triode BG1 to form a half-wave shaping circuit, which is used to convert the alternating voltage signal of the AC power source 1 obtained at the junction of the resistors R1 and R2 into a rectangular wave signal.

In order to make the rectangular wave signal strong enough, at the output end of the half-wave shaping circuit, that is, at the junction of the collector of the triode BG1 and the resistor R4, there is connected in series between the power supply VCC and the ground, which is composed of the triode BG2 and the resistor R5. amplifier.

The frequency dividing part 22 is a CD4520 integrated block; wherein, the input terminal pin ① of the CD4520 integrated block is connected to the output end of the aforementioned amplifier, the pins ③～⑥ are the output terminals, the pin  is connected to VCC, and the pin ⑧ is grounded, which is used for setting relative to the AC The charging frequency of power supply 1 frequency; the charging frequency set here can be selected as 3.0625Hz or 6.125Hz or 12.5Hz or 25Hz respectively.

The delay component 23 is composed of a CD4538 integrated block, a variable resistor RW1, and a capacitor C1. Among them, the input terminal pin ④ of the CD4538 integrated block is connected to the output terminal of the frequency division component 22, the pin ⑩ is the output terminal, and the pin ① is connected in series with VCC Capacitor C1 and variable resistor RW1, pin ② are connected to the contact point of capacitor C1 and variable resistor RW1, pin  is connected to VCC, and pin ⑧ is grounded, which is used to determine the delay time when the zero-crossing point is output relative to the AC power supply 1, and When the delay time arrives, output a trigger pulse with a width greater than zero and one half cycle of the AC power supply; here, the parameters of the variable resistor RW1 and capacitor C1 are selected to make the trigger pulse trigger at the set time.

In order to increase the driving power of the trigger pulse, an amplifier 24 is connected in series between the output end of the delay component 23, that is, the pin ⑩ of the CD4538 integrated block and the gate of the thyristor 5.

Now take the AC power supply 1 as the mains 220V with a power frequency of 50Hz (see a diagram in Figure 3), and when the charging frequency is selected as 12.5Hz, the working process of the present utility model is described: when the mains 220V crosses the zero point, the pulse trigger The alternating voltage sampling part in the device 2 sends the zero-crossing signal to the delay part 23 through the frequency division part 22, so that it starts to delay. When the negative half cycle of the mains 220V arrives, the negative half cycle voltage charges the capacitor 3 through the rectifier diode 4, until the 1/4 alternating cycle of the AC power supply 1, the voltage charged on the capacitor 3 is $220V\×\sqrt{2}=311V;$ The voltage divider of the alternating voltage sampling part in the pulse trigger 2 samples the negative half-cycle signal, and it is shaped into a rectangular wave by the half-wave shaping circuit (see figure b in Figure 3), and then through the triode BG2 and After the amplifier formed by resistor R5 is amplified, it enters the frequency division part 22, and the power frequency of 50 Hz is converted into a charging frequency of 12.5 Hz by the frequency division part 22 (see figure c in Fig. 3), and then sent to the delay part 23, and then by Delay part 23 is in the 1/4 alternating period of AC power supply 1 to amplifier 24 output width is the trigger pulse of the half period of AC power supply 1 (see d figure in Fig. 3), this trigger pulse is sent after amplifier 24 amplifies To the gate of SCR 5. The thyristor 5 is turned on at the peak value of the negative half cycle of the AC power supply 1, and the voltage of the rising half cycle of the AC power supply 1, that is, $2\×220V\×\sqrt{2}=622V$ Charge to the energy storage capacitor 6 (see e diagram among Fig. 3). If the voltage charged on the energy storage capacitor 6 only needs to be a certain voltage value between 0～622V, then the voltage value can be input into the voltage setting device of the charging voltage controller 8, when the energy storage capacitor 6 When the charged voltage reaches the voltage value, the turn-off switch 7 automatically cuts off the charging circuit of the thyristor 5 under the control of the charging voltage controller 8 . After that, the pulse discharge of the xenon lamp of the solid-state laser is completed by other functional components.

Apparently, those skilled in the art can make various changes and modifications to the transformerless laser pulse power supply of the utility model without departing from the spirit and scope of the utility model. In this way, if these modifications and variations of the utility model fall within the scope of the claims of the utility model and equivalent technologies thereof, the utility model is also intended to include these modifications and variations.

Claims (7)

1, a kind of dereliction transformer type laser pulse power supply, comprise the rectifier diode (4) and the energy storage capacitor (6) that are electrically connected with AC power (1), it is characterized in that the anode of said rectifier diode (4) and an end of said energy storage capacitor (6), and an end of said AC power (1) is electrically connected, the negative terminal of said rectifier diode (4) is electrically connected through capacitor (3) with the other end of said AC power (1), be serially connected with controllable silicon (5) between the other end of the negative terminal of said rectifier diode (4) and said energy storage capacitor (6), the two ends span of said AC power (1) is connected to pulse trigger (2), the output of said pulse trigger (2) is electrically connected with the gate pole of said controllable silicon (5), so that controllable silicon (5) conducting when AC power (1) negative half period maximum.

2, dereliction transformer type laser pulse power supply according to claim 1 is characterized in that pulse trigger (2) is by alternating voltage sampled part (21), frequency division parts (22) and the time delay part (23) of electricity serial connection constitute successively; Said alternating voltage sampled part (21) is made up of voltage divider and half-wave shaping circuit, wherein, the two ends cross-over connection of the voltage divider that is composed in series by resistance R 1, R2 is on AC power (1), obtain the alternating voltage signal of AC power (1) with contact place by resistance R 1, R2, be connected in series mutually by the base stage of diode D1, resistance R 3 and triode BG1 and constitute the half-wave shaping circuit, be used for the alternating voltage conversion of signals of voltage divider output is become square-wave signal; Said frequency division parts (22) are the CD4520 integrated package, wherein, 3.～6. output, pin that 1. the input pin of CD4520 integrated package connects alternating voltage sampled part (21) connect 8. ground connection of VCC, pin for output, pin , are used for setting the charge frequency with respect to AC power (1) frequency; Said time delay part (23) is made up of CD4538 integrated package and variable resistor RW1, capacitor C 1, wherein, 1. with between VCC the output, pin that 4. the input pin of CD4538 integrated package connects frequency division parts (22) 10. be connected in series that 2. capacitor C 1 and variable resistor RW1, pin join with the contact of capacitor C 1 and variable resistor RW1, pin  connects 8. ground connection of VCC, pin for output, pin, delay time when being used for determining with respect to AC power (1) output zero crossing, and when this delay time arrives the output width greater than the trigger impulse of zero-sum AC power between (1) half period.

3, dereliction transformer type laser pulse power supply according to claim 2, it is characterized in that frequency division parts (22) the CD4520 integrated package the input pin 1. and be serially connected with the amplifier that constitutes by triode BG2 and resistance R 5 between the output of alternating voltage sampled part (21).

4, dereliction transformer type laser pulse power supply according to claim 2 is characterized in that the output pin of the CD4538 integrated package of time delay part (23) 10. connects amplifier (24).

5, dereliction transformer type laser pulse power supply according to claim 1, it is characterized in that the contact of capacitor (3) and rectifier diode (4) negative terminal and controllable silicon (5) but between be serially connected with stopcock (7), the two ends cross-over connection of energy storage capacitor (6) has charging voltage controller (8), said charging voltage controller (8) but the control end of the said stopcock of output termination (7).

6, dereliction transformer type laser pulse power supply according to claim 5, but it is characterized in that stopcock (7) is a high-power MOSFET tube.

7, dereliction transformer type laser pulse power supply according to claim 5, it is characterized in that charging voltage controller (8) is for the input of comparison circuit is electrically connected with sample circuit and voltage setting device, output is serially connected with amplifying circuit and buffer circuit, the input cross-over connection of said sample circuit is in the two ends of energy storage capacitor (6), but the output of said buffer circuit is electrically connected with the control end of stopcock (7).

Images