Pulse power supply with voltage-stabilizing and current-stabilizing switching function

Abstract

The utility model discloses a pulse power supply with a voltage stabilization and current stabilization switching function. A rectification inverter circuit inputs power frequency alternating current and outputs controllable direct current, and a chopper circuit inputs the controllable direct current and outputs pulse current; the inversion control circuit inputs a voltage control signal and outputs a pulse width driving signal to the rectification inversion circuit; the voltage stabilization acquisition circuit is used for acquiring a voltage signal of the controllable direct current and outputting a voltage stabilization signal to the selection circuit; the steady-current acquisition circuit is used for acquiring a current signal of the controllable direct current and outputting a steady-current signal to the selection circuit; the selection circuit is used for selecting a voltage-stabilizing signal or a current-stabilizing signal according to a selection signal and outputting the signal to the input comparison circuit; the input comparison circuit is used for outputting a voltage control signal to the inversion control circuit according to the selected voltage stabilization signal or current stabilization signal and a reference voltage. The beneficial effects are that voltage stabilization and current stabilization of controllable direct current can be realized, and switching between voltage stabilization and current stabilization can be carried out.

Description

Technical Field

[0001] The utility model relates to the technical field of pulse power supplies, in particular to a pulse power supply with voltage and current stabilization switching functions. Background Art

[0002] High-frequency pulse power supply is suitable for electroplating gold, silver, nickel, tin, and alloys, and can significantly improve the functionality of the coating. It includes a rectifier and inverter circuit that converts industrial frequency AC power into DC power, and a chopper circuit that converts DC power into pulse power. By controlling the duty cycle of the pulse width drive signal sent to the rectifier and inverter circuit, the current and voltage of the DC power can be controlled.

[0003] By directly setting the duty cycle of the pulse width drive signal, the final output pulse power can reach the required voltage or current. However, when the duty cycle is directly set, the voltage or current of the DC power is open-loop controlled and there is no voltage or current stabilization function. Secondly, there is no special selection circuit to switch between voltage stabilization and current stabilization to ensure that the same pulse power supply has both voltage stabilization and current stabilization functions. Utility Model Content

[0004] In view of at least one defect of the prior art, the purpose of the present invention is to provide a pulse power supply with voltage and current stabilization switching function, which can achieve voltage and current stabilization of controllable direct current and can switch between voltage and current stabilization.

[0005] In order to achieve the above object, the utility model adopts the following technical solution: a pulse power supply with a voltage and current stabilization switching function, comprising a rectifier inverter circuit and a chopper circuit, the rectifier inverter circuit inputs industrial frequency alternating current and outputs controllable direct current, the chopper circuit inputs controllable direct current and outputs pulse power;

[0006] The inverter control circuit also includes an inverter control circuit, which inputs a voltage control signal and outputs a pulse width drive signal to the rectifier inverter circuit, controls the duty cycle of the pulse width drive signal according to the voltage control signal, and further controls the voltage and current of the controllable direct current;

[0007] The key lies in: it also includes a voltage stabilization acquisition circuit, a current stabilization acquisition circuit, a selection circuit and an input comparison circuit;

[0008] The voltage stabilization acquisition circuit is used to: collect the voltage signal of the controllable direct current and output the stabilization signal to the selection circuit;

[0009] The steady current acquisition circuit is used to: collect the current signal of the controllable direct current and output the steady current signal to the selection circuit;

[0010] The selection circuit is used to select a voltage stabilization signal or a current stabilization signal according to a selection signal and output it to the input comparison circuit;

[0011] The input comparison circuit is used to output a voltage control signal to the inverter control circuit according to the selected voltage stabilization signal or current stabilization signal and the reference voltage, thereby controlling the duty cycle of the pulse width drive signal to achieve voltage stabilization or current stabilization function.

[0012] The voltage stabilization acquisition circuit or the current stabilization acquisition circuit, the selection circuit, the input comparison circuit, the inverter control circuit and the rectifier inverter circuit constitute a closed-loop control circuit, which can perform closed-loop control on the voltage or current of the controllable direct current to achieve the voltage stabilization or current stabilization function; by adjusting the value of the reference voltage, the voltage stabilization value or current stabilization value of the controllable direct current can be adjusted; the selection of voltage stabilization or current stabilization is achieved through the selection circuit.

[0013] Furthermore, the voltage stabilization acquisition circuit mainly includes an operational amplifier U9;

[0014] The front end of the resistor R501 inputs the voltage signal of the controllable direct current, the rear end of the resistor R501 is connected to the front end of the adjustable resistor VR2, the rear end of the adjustable resistor VR2 is connected in series with a resistor R502 and then grounded, the sliding end of the adjustable resistor VR2 is connected to the front end of the resistor R503, the rear end of the resistor R503 is connected in series with a resistor R504 and then grounded, and the common end of the resistor R503 and the resistor R504 is connected in series with a resistor R506 and then connected to the same-direction end of the operational amplifier U9;

[0015] The reverse end of the operational amplifier U9 is connected in series with a resistor R507 and then grounded; between the output end and the reverse end of the operational amplifier U9, a resistor R508 and a capacitor C503 are connected in parallel; the output end of the operational amplifier U9 is connected to the front end of the resistor R510, and the rear end of the resistor R510 outputs the regulated voltage signal;

[0016] The two zero-adjust bias terminals of the operational amplifier U9 are connected to the two ends of the adjustable resistor VR1. The sliding terminal of the adjustable resistor VR1 is connected in series with the resistor R509 and then connected to the -12V power supply terminal.

[0017] The steady current acquisition circuit mainly includes an operational amplifier U10 and an operational amplifier U11;

[0018] The front end of the resistor R511 inputs the current signal of the controllable direct current, the rear end of the resistor R511 is connected to the front end of the resistor R512, the rear end of the resistor R512 is connected to the reverse terminal of the operational amplifier U10, the same-direction terminal of the operational amplifier U10 is grounded, and a resistor R513 is connected in parallel between the reverse terminal and the output terminal of the operational amplifier U10, and a capacitor C508 is connected in parallel at both ends of the resistor R513;

[0019] The output end of the operational amplifier U10 is connected to the front end of the resistor R514, the rear end of the resistor R514 is connected in series with the resistor R515 and then grounded, the two ends of the resistor R514 are connected in parallel with the two ends of the adjustable resistor VR4, the sliding end of the adjustable resistor VR4 is connected to the same direction end of the operational amplifier U11, and the reverse direction end of the operational amplifier U11 is connected in series with the resistor R516 and then grounded;

[0020] A resistor R517 is connected in parallel between the reverse terminal and the output terminal of the operational amplifier U11, and a capacitor C512 is connected in parallel across both ends of the resistor R517; the output terminal of the operational amplifier U11 is connected to the front end of the resistor R519, and the rear end of the resistor R519 outputs the regulated voltage signal;

[0021] The two zero-adjust bias terminals of the operational amplifier U11 are connected to the two ends of the adjustable resistor VR3. The sliding terminal of the adjustable resistor VR3 is connected in series with the resistor R512 and then connected to the -12V power supply terminal.

[0022] The selection circuit mainly includes an operational amplifier U15C and a selection chip U16;

[0023] The L5V power supply end is connected to the front end of resistor R703, the rear end of resistor R703 is connected to the same-direction terminal of operational amplifier U15C, the +12V power supply end is connected to the cathode of diode D703, the anode of diode D703 is connected to the cathode of diode D704, and the anode of diode D704 is grounded; the common end of diode D703 and diode D704 is connected to the front end of resistor R704, the front end of resistor R704 also inputs the selection signal, the rear end of resistor R704 is connected to the reverse terminal of operational amplifier U15C, and resistor R702 is connected in parallel between the cathode and anode of diode D703;

[0024] The output end of the operational amplifier U15C is connected to the positive electrode of the light-emitting diode ED4, and the negative electrode of the light-emitting diode ED4 is connected in series with the resistor R705 and then grounded;

[0025] The selection chip U16 is a four-way selection chip CD4066; the first input end of the selection chip U16 is connected to the output end of the voltage stabilization acquisition circuit, the second input end of the selection chip U16 is connected to the output end of the current stabilization acquisition circuit, and the first output end and the second output end of the selection chip U16 are connected together and connected to the input comparison circuit;

[0026] The +12V power supply terminal is connected to the front end of the resistor R710, the rear end of the resistor R710 is connected to the first control terminal and the third input terminal of the selection chip U16, and the third output terminal of the selection chip is grounded;

[0027] The output end of the operational amplifier U15C is connected to the front end of the resistor R706, and the rear end of the resistor R706 is connected to the second control end and the third control end of the selection chip U16;

[0028] The input comparison circuit mainly includes an operational amplifier U5A;

[0029] The reference voltage is input to the front end of resistor R307, the rear end of resistor R307 is connected to the front end of resistor R308, the rear end of resistor R308 is grounded, the common end of resistor R307 and resistor R308 is connected in series with resistor R309 and then connected to the reverse end of operational amplifier U5A, the same-direction end of operational amplifier U5A is connected to the output end of the selection circuit, the output end of operational amplifier U5A is connected to the positive electrode of diode D304, and the negative electrode of diode D304 outputs the voltage-controlled signal.

[0030] In the selection circuit, when the selection signal is low or floating;

[0031] When the selection signal is left floating, after the 12V voltage is divided by the diodes D703 and D704, the voltage at the same-direction terminal of the operational amplifier U15C is less than the voltage at the reverse terminal. The operational amplifier U15C outputs a low level to the second control terminal and the third control terminal of the selection chip U16. The second input terminal and the output terminal of the selection chip U16 are disconnected, the third input terminal and the output terminal of the selection chip U16 are disconnected, the first control terminal of the selection chip U16 is high, the first input terminal and the output terminal of the selection chip U16 are turned on, and the signal of the voltage stabilization acquisition circuit is selected;

[0032] When the selection signal is at a low level, the voltage at the same-direction terminal of the operational amplifier U15C is greater than the voltage at the reverse terminal. The operational amplifier U15C outputs a high level to the second control terminal and the third control terminal of the selection chip U16. The second input terminal and the output terminal of the selection chip U16 are turned on, and the third input terminal and the output terminal of the selection chip U16 are turned on, pulling the first control terminal of the selection chip U16 to a low level, thereby disconnecting the first input terminal and the output terminal of the selection chip U16, and selecting the signal of the steady current acquisition circuit.

[0033] Furthermore, the selection circuit further includes an operational amplifier U15D;

[0034] The first control terminal of the selection chip U16 is also connected to the front end of the capacitor C705, the rear end of the capacitor C705 is connected in series with the resistor R709 and then grounded, and the rear end of the capacitor C705 is connected to the positive electrode of the diode D706;

[0035] The second control end of the selection chip U16 is also connected to the front end of the capacitor C704, the rear end of the capacitor C704 is connected in series with a resistor R707 and then grounded, and the rear end of the capacitor C704 is connected to the positive electrode of the diode D705; the cathode of the diode D705 is connected to the cathode of the diode D706, the common end of the diode D705 and the diode D706 is connected in series with a resistor R708 and then grounded, the common end of the diode D705 and the diode D706 is connected to the same direction end of the operational amplifier U15D, the +12V power supply end is connected to the front end of the resistor R701, the rear end of the resistor R701 is connected in series with a reverse voltage zener diode D701 and then grounded, the common end of the resistor R701 and the voltage zener diode D701 is connected to the reverse end of the operational amplifier U15D, the output end of the operational amplifier U15 is connected to the front end of the diode D702, and the rear end of the diode D706 outputs a switching signal;

[0036] The input comparison circuit also includes a selection chip U20,

[0037] The positive electrode of the diode D904 inputs the switching signal, the negative electrode of the diode D904 is connected to the ground after being connected to the resistor R914, the negative electrode of the diode D904 is connected to the control end of the selection chip U20, the input end of the selection chip U20 is connected to the front end of the resistor R318, the front end of the resistor R915, the back end of the resistor R915 is connected to the input end of the selection chip U20, the output end of the selection chip U20 is grounded, and the resistance of the resistor R915 is 5Ω.

[0038] During the switching process of selecting the voltage-stabilized signal or the current-stabilized signal, a switching signal is generated, and the switching signal is used to pull the reverse end of the input comparison circuit to a low level, thereby ensuring that the duty cycle of the pulse width drive signal is zero during the switching process, thereby avoiding circuit failure during the switching process.

[0039] Furthermore, the inverter control circuit also obtains the switching signal and directly controls the duty cycle of the pulse width drive signal outputted by the inverter control circuit to be zero.

[0040] The duty cycle of the pulse width drive signal is controlled to be zero by switching the signal, thereby avoiding circuit failure during the switching process.

[0041] Furthermore, the inverter control circuit includes a pulse width modulation circuit and a pulse width drive circuit;

[0042] After the pulse width modulation circuit inputs the voltage control signal, it outputs a pulse width control signal; after the inverter drive circuit inputs the pulse width control signal, it outputs a pulse width drive signal;

[0043] The pulse width modulation circuit is used to: control the duty cycle of the pulse width control signal according to the voltage control signal;

[0044] The pulse width drive circuit is used to: isolate and improve the driving capability of the pulse width drive signal.

[0045] Since the switching tubes in the rectifier and inverter circuits have high power and are fragile devices, directly using a pulse width modulation circuit for control will firstly result in insufficient driving capability and secondly easily damage the pulse width modulation circuit and other circuits connected to the pulse width modulation circuit. However, using a pulse width drive circuit can achieve isolation and improve the driving capability of the pulse width drive signal.

[0046] Furthermore, the pulse width modulation circuit includes a pulse width modulation chip U4, and the model of the pulse width modulation chip U4 is SW494;

[0047] The +V1 terminal of the pulse width modulation chip U4 is connected to a resistor R302 in series and then to ground. The +V2 terminal of the pulse width modulation chip U4 is connected to a resistor R301 in series and then to ground. The -V1 terminal and -V2 terminal of the pulse width modulation chip U4 are connected to a resistor R303 in series and then to ground. The voltage control signal is input to the +V1 terminal or the +V2 terminal of the pulse width modulation chip U4.

[0048] The E1 and E2 terminals of the pulse width modulation chip U4 output two sets of pulse width control signals with complementary dead zones;

[0049] Short-circuit the first and third pins of terminal group JP7 to ground the E1 and E2 terminals of the pulse width modulation chip U4, forcing the duty cycle to zero.

[0050] By using a complementary pulse width control signal with a dead zone, current conflicts and short circuits caused by the conduction and switching of the switch tubes in the rectifier inverter circuit can be avoided.

[0051] Furthermore, the -V1 and -V2 terminals of the pulse width modulation chip U4 are connected in series with capacitors C304 and then grounded; the +V1 terminal of the pulse width modulation chip U4 is connected in series with capacitors C303 and then grounded; the +V2 terminal of the pulse width modulation chip U4 is connected in series with capacitors C301 and then grounded; and the +V2 terminal of the pulse width modulation chip U4 is connected in series with capacitors C302 and then grounded.

[0052] The voltage control signal input from the +V1 terminal of the pulse width modulation chip U4 is filtered through capacitor C303, and the voltage control signal input from the +V2 terminal of the pulse width modulation chip U4 is filtered and prevented from sudden changes through capacitors C301 and C302.

[0053] Furthermore, the pulse width driving circuit includes an optocoupler isolation chip U1;

[0054] The E1 terminal of the pulse width modulation chip U4 is connected to the front end of the resistor R103, the rear end of the resistor R103 is connected to the positive input terminal of the optocoupler isolation chip U1, and the negative input terminal of the optocoupler isolation chip U1 is grounded;

[0055] The output end of the optocoupler isolation chip U1 is connected to the base of the NPN transistor Q1 and the PNP transistor Q2, the +20V power supply end is connected to the collector of the transistor Q1, the emitter of the transistor Q1 is connected to the emitter of the transistor Q2, and the collector of the transistor Q2 is grounded; the common end of the transistor Q1 and the transistor Q2 outputs the pulse width drive signal.

[0056] The isolation function is achieved through the optocoupler isolation chip of the pulse width drive circuit, and the driving capability of the pulse width drive signal is enhanced through the push-pull output circuit composed of NPN type transistors and PNP type transistors.

[0057] Furthermore, the +20V power supply terminal is connected to the front end of the resistor R101, the rear end of the resistor R101 is connected in series with a reverse voltage zener diode D101 and then grounded, and the common end of the resistor R101 and the voltage zener diode D101 is connected to the second pin of the terminal group JP1;

[0058] The common end of the transistor Q1 and the transistor Q2 is connected to the front end of the resistor R107, the rear end of the resistor R107 is connected to the front end of the resistor R108, and the rear end of the resistor R108 is connected to the second pin of the terminal group JP1; the common end of the resistor R107 and the resistor R108 is connected to the first pin of the terminal group JP1;

[0059] A bidirectional voltage regulator diode DW1 is connected in series between the first and second pins of the terminal group JP1;

[0060] When the transistor Q1 is turned on, a positive voltage is applied between the first pin and the second pin of the terminal group JP1; when the transistor Q2 is turned on, a negative voltage is applied between the first pin and the second pin of the terminal group JP1;

[0061] The first pin and the second pin of the terminal group JP1 output a group of pulse width driving signals.

[0062] When the transistor Q2 is turned on, a negative voltage is present between the first and second pins of the terminal group JP1, realizing the reverse shutdown function of the pulse width drive signal. The reverse shutdown voltage value of the pulse width drive signal is the regulated voltage value of the Zener diode D101, and the forward conduction voltage value of the pulse width drive signal is the regulated voltage value of the bidirectional Zener diode DW1.

[0063] Furthermore, the collector series capacitor C101 of the transistor Q1 is connected to the collector of the transistor Q2; the collector series capacitor C102 of the transistor Q1 is connected to the collector of the transistor Q2; the reverse voltage zener diode D101 is connected in parallel with the capacitor C103; and the reverse voltage zener diode D101 is connected in parallel with the capacitor C104.

[0064] The capacitors C103 and C104 can filter the signal output from the first pin of the terminal group JP1 and smooth the startup impact; the capacitors C103 and C104 can filter the signal output from the second pin of the terminal group JP1 and smooth the startup impact.

[0065] Significant effect: The utility model provides a pulse power supply with voltage and current stabilization switching function, which realizes voltage and current stabilization of controllable direct current and can switch between voltage and current stabilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 This is a module structure diagram of the utility model;

[0067] Figure 2 This is the schematic diagram of the rectifier inverter circuit;

[0068] Figure 3 This is the schematic diagram of the pulse width modulation circuit;

[0069] Figure 4 This is the schematic diagram of the pulse width drive circuit;

[0070] Figure 5 This is the schematic diagram of the voltage stabilization acquisition circuit;

[0071] Figure 6 This is the schematic diagram of the steady current acquisition circuit;

[0072] Figure 7 Schematic diagram for selecting circuit;

[0073] Figure 8 This is the schematic diagram of the input comparison circuit. DETAILED DESCRIPTION

[0074] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0075] like Figure 1 As shown, a pulse power supply with a voltage and current stabilization switching function includes a rectifier inverter circuit and a chopper circuit. The rectifier inverter circuit inputs industrial frequency AC power and outputs controllable DC power. The chopper circuit inputs controllable DC power and outputs pulse power.

[0076] The inverter control circuit also includes an inverter control circuit, which inputs a voltage control signal and outputs a pulse width drive signal to the rectifier inverter circuit, controls the duty cycle of the pulse width drive signal according to the voltage control signal, and further controls the voltage and current of the controllable direct current;

[0077] It also includes a voltage stabilization acquisition circuit, a current stabilization acquisition circuit, a selection circuit and an input comparison circuit;

[0078] The voltage stabilization acquisition circuit is used to: collect the voltage signal of the controllable direct current and output the stabilization signal to the selection circuit;

[0079] The steady current acquisition circuit is used to: collect the current signal of the controllable direct current and output the steady current signal to the selection circuit;

[0080] The selection circuit is used to select a voltage stabilization signal or a current stabilization signal according to a selection signal and output it to the input comparison circuit;

[0081] The input comparison circuit is used to output a voltage control signal to the inverter control circuit according to the selected voltage stabilization signal or current stabilization signal and the reference voltage, thereby controlling the duty cycle of the pulse width drive signal to achieve voltage stabilization or current stabilization function.

[0082] The voltage stabilization acquisition circuit or the current stabilization acquisition circuit, the selection circuit, the input comparison circuit, the inverter control circuit and the rectifier inverter circuit constitute a closed-loop control circuit, which can perform closed-loop control on the voltage or current of the controllable direct current to achieve the voltage stabilization or current stabilization function; by adjusting the value of the reference voltage, the voltage stabilization value or current stabilization value of the controllable direct current can be adjusted; the selection of voltage stabilization or current stabilization is achieved through the selection circuit.

[0083] It also includes a low-power power supply, which uses existing mature technology to provide +20V power supply end, +12V power supply end, -12V power supply end, and L5V power supply end to power the inverter control circuit, voltage stabilization acquisition circuit, current stabilization acquisition circuit, selection circuit and input comparison circuit.

[0084] The rectifier and inverter circuit includes an industrial frequency rectifier circuit, a first filter circuit, a high frequency inverter circuit, a high frequency rectifier circuit, and a second filter circuit connected in sequence;

[0085] The power frequency rectifier circuit is used to: rectify the input three-phase AC power;

[0086] The first filter circuit is used to filter out the three-phase ripple generated after rectification by the power frequency rectification circuit.

[0087] The high-frequency inverter circuit is used to: invert the direct current output by the first filter circuit into high-frequency alternating current according to the pulse width drive signal, and perform voltage boosting or voltage reduction;

[0088] High-frequency rectifier circuit is used to: rectify high-frequency AC power into DC power;

[0089] The second filter circuit is used to filter out the high-frequency ripple generated after rectification by the high-frequency rectification circuit and output the controllable direct current.

[0090] like Figure 2 As shown, the power frequency rectifier circuit is a three-phase full-bridge rectifier circuit composed of diode D91, diode D92, diode D93, diode D94, diode D5 and diode D6. The power frequency rectifier circuit inputs three-phase AC power and outputs DC power with three-phase ripple.

[0091] The first filter circuit is composed of an inductor L11, a capacitor C11 and a capacitor C12, and filters the DC power with three-phase ripple;

[0092] The high-frequency inverter circuit is composed of switching tubes IGBT1, IGBT2, IGBT3, IGBT4, an overcurrent sampling resistor R815, and a transformer T1. The inverter circuit composed of switching tubes IGBT1, IGBT2, IGBT3, and IGBT4 inverts the DC power output by the first filter circuit into high-frequency AC power, which is then stepped up or down by transformer T1. The overcurrent sampling resistor R815 can perform current sampling on the inverted high-frequency AC power.

[0093] The high-frequency rectifier circuit mainly includes diode D96 and diode D97. The two ends of the secondary side of transformer T1 are connected to the positive electrodes of diode D96 and diode D97 respectively. The negative electrodes of diode D96 and diode D97 serve as the positive output terminal of the high-frequency rectifier circuit. The center tap of the secondary side of transformer T1 serves as the negative output terminal of the high-frequency rectifier circuit. The high-frequency rectifier circuit rectifies the high-frequency AC power that has been stepped up or down by transformer T1 into DC power with high-frequency ripple.

[0094] The second filter circuit mainly includes an inductor L12, which filters out high-frequency ripples so that the controllable DC power it outputs has no ripples.

[0095] By inputting a set of pulse width drive signals to the gates of IGBT1 and IGBT4, or inputting another set of pulse width drive signals to the gates of IGBT2 and IGBT3, the controllable DC power output by the second filter circuit can be controlled. The two sets of pulse width drive signals are complementary and have dead zones. When the duty cycle of the pulse width drive signal is zero, the high-frequency inverter circuit stops inverting, and the voltage and current of the controllable DC power output are zero.

[0096] The pulse width drive signal is output by the inverter control circuit, and the duty cycle of the pulse width drive signal is controlled by the voltage control signal input to the inverter control circuit;

[0097] like Figure 1 As shown, the inverter control circuit includes a pulse width modulation circuit and a pulse width drive circuit;

[0098] After the pulse width modulation circuit inputs the voltage control signal, it outputs a pulse width control signal; after the inverter drive circuit inputs the pulse width control signal, it outputs a pulse width drive signal;

[0099] The pulse width modulation circuit is used to: control the duty cycle of the pulse width control signal according to the voltage control signal;

[0100] The pulse width drive circuit is used to: isolate and improve the driving capability of the pulse width drive signal.

[0101] Since the switching tubes in the rectifier and inverter circuits have high power and are fragile devices, when the pulse width modulation circuit is directly used for control, firstly, the driving capability is insufficient, and secondly, the pulse width modulation circuit and other circuits connected to the pulse width modulation circuit are easily damaged. However, the pulse width drive circuit not only achieves isolation, but also improves the driving capability of the pulse width drive signal.

[0102] like Figure 3 As shown, the pulse width modulation circuit includes a pulse width modulation chip U4, and the model of the pulse width modulation chip U4 is SW494;

[0103] The +V1 terminal of the pulse width modulation chip U4 is connected to a resistor R302 in series and then to ground. The +V2 terminal of the pulse width modulation chip U4 is connected to a resistor R301 in series and then to ground. The -V1 terminal and -V2 terminal of the pulse width modulation chip U4 are connected to a resistor R303 in series and then to ground. The voltage control signal is input to the +V1 terminal or the +V2 terminal of the pulse width modulation chip U4.

[0104] The E1 and E2 terminals of the pulse width modulation chip U4 output two sets of pulse width control signals with complementary dead zones;

[0105] The RT end of the pulse width modulation chip U4 is connected to the front end of the resistor R305, the rear end of the resistor R305 is connected to the front end of the resistor R306, and the rear end of the resistor R306 is grounded; the CT end of the pulse width modulation chip U4 is connected in series with the capacitor C306 and then grounded, the VREF end of the pulse width modulation chip U4 is connected to the front end of the resistor R330, the rear end of the resistor R330 is connected to the front end of the resistor R304, and the rear end of the resistor R304 is grounded, and the common end of the resistor R330 and the resistor R304 is connected to the DTC end of the pulse width modulation chip U4; the VREF end and the 0C end of the pulse width modulation chip U4 are connected to the L5V power supply end;

[0106] By adjusting the capacitance or resistance of capacitor C306, resistor R305 and resistor R306, the frequency of the pulse width control signal is adjusted; by adjusting the resistance of resistor R330 and resistor R304, the dead time of the pulse width control signal output from the E1 terminal and the E2 terminal of the pulse width modulation chip U4 is adjusted;

[0107] By adjusting the voltage control signal input to the +V1 terminal or the +V2 terminal of the pulse width modulation chip U4, the duty cycle of the pulse width control signal output from the E1 terminal and the E2 terminal of the pulse width modulation chip U4 is adjusted;

[0108] By using a complementary pulse width control signal with a dead zone, current conflicts and short circuits caused by the conduction and switching of the switch tubes in the rectifier inverter circuit can be avoided.

[0109] The E1 terminal of the pulse width modulation chip U4 is connected to the anode of the diode D301, the E2 terminal of the pulse width modulation chip U4 is connected to the anode of the diode D302, the cathode of the diode D301 is connected to the cathode of the diode D302, the common terminal of the diode D301 and the diode D302 is connected in series with a resistor R313 and then grounded, the common terminal of the diode D301 and the diode D302 is connected to the first pin of the terminal group JP7, and the third pin of the terminal group JP7 is grounded;

[0110] Short-circuit the first and third pins of terminal group JP7 to ground the E1 and E2 terminals of the pulse width modulation chip U4, forcing the duty cycle to zero.

[0111] The -V1 and -V2 terminals of the pulse width modulation chip U4 are connected in series with capacitors C304 and then grounded; the +V1 terminal of the pulse width modulation chip U4 is connected in series with capacitors C303 and then grounded; the +V2 terminal of the pulse width modulation chip U4 is connected in series with capacitors C301 and then grounded; the +V2 terminal of the pulse width modulation chip U4 is connected in series with capacitors C302 and then grounded.

[0112] The voltage control signal input from the +V1 terminal of the pulse width modulation chip U4 is filtered through the capacitor C303, and the voltage control signal input from the +V2 terminal of the pulse width modulation chip U4 is filtered through the capacitors C301 and C302.

[0113] like Figure 4 As shown, the pulse width driving circuit includes two groups of isolated driving circuits with the same structure. Taking the first group of isolated driving circuits as an example:

[0114] The E1 terminal of the pulse width modulation chip U4 is connected to the front end of the resistor R103, the rear end of the resistor R103 is connected to the positive input terminal of the optocoupler isolation chip U1, and the negative input terminal of the optocoupler isolation chip U1 is grounded;

[0115] The output end of the optocoupler isolation chip U1 is connected to the base of the NPN transistor Q1 and the PNP transistor Q2, the +20V power supply end is connected to the collector of the transistor Q1, the emitter of the transistor Q1 is connected to the emitter of the transistor Q2, and the collector of the transistor Q2 is grounded; the common end of the transistor Q1 and the transistor Q2 outputs the pulse width drive signal;

[0116] The isolation function is achieved through the optocoupler isolation chip of the pulse width drive circuit, and the driving capability of the pulse width drive signal is enhanced through the push-pull output circuit composed of NPN type transistors and PNP type transistors.

[0117] The +20V power supply terminal is connected to the front end of the resistor R101, the rear end of the resistor R101 is connected in series with a reverse voltage zener diode D101 and then grounded, and the common end of the resistor R101 and the voltage zener diode D101 is connected to the second pin of the terminal group JP1;

[0118] The common end of the transistor Q1 and the transistor Q2 is connected to the front end of the resistor R107, the rear end of the resistor R107 is connected to the front end of the resistor R108, and the rear end of the resistor R108 is connected to the second pin of the terminal group JP1; the common end of the resistor R107 and the resistor R108 is connected to the first pin of the terminal group JP1;

[0119] A bidirectional voltage regulator diode DW1 is connected in series between the first and second pins of the terminal group JP1;

[0120] When the transistor Q1 is turned on, a positive voltage is applied between the first pin and the second pin of the terminal group JP1; when the transistor Q2 is turned on, a negative voltage is applied between the first pin and the second pin of the terminal group JP1;

[0121] The first pin and the second pin of the terminal group JP1 output a group of pulse width driving signals.

[0122] When the transistor Q2 is turned on, a negative voltage is present between the first and second pins of the terminal group JP1, realizing the reverse shutdown function of the pulse width drive signal. The reverse shutdown voltage value of the pulse width drive signal is the regulated voltage value of the Zener diode D101, and the forward conduction voltage value of the pulse width drive signal is the regulated voltage value of the bidirectional Zener diode DW1.

[0123] The collector series capacitor C101 of the transistor Q1 is connected to the collector of the transistor Q2; the collector series capacitor C102 of the transistor Q1 is connected to the collector of the transistor Q2; the reverse voltage zener diode D101 is connected in parallel with the capacitor C103; the reverse voltage zener diode D101 is connected in parallel with the capacitor C104.

[0124] The capacitors C103 and C104 can filter the signal output from the first pin of the terminal group JP1 and smooth the startup impact; the capacitors C103 and C104 can filter the signal output from the second pin of the terminal group JP1 and smooth the startup impact.

[0125] like Figure 5 As shown, the voltage stabilization acquisition circuit mainly includes an operational amplifier U9;

[0126] The front end of the resistor R501 inputs the voltage signal of the controllable direct current, the rear end of the resistor R501 is connected to the front end of the adjustable resistor VR2, the rear end of the adjustable resistor VR2 is connected in series with a resistor R502 and then grounded, the sliding end of the adjustable resistor VR2 is connected to the front end of the resistor R503, the rear end of the resistor R503 is connected in series with a resistor R504 and then grounded, and the common end of the resistor R503 and the resistor R504 is connected in series with a resistor R506 and then connected to the same-direction end of the operational amplifier U9;

[0127] The reverse end of the operational amplifier U9 is connected in series with a resistor R507 and then grounded; between the output end and the reverse end of the operational amplifier U9, a resistor R508 and a capacitor C503 are connected in parallel; the output end of the operational amplifier U9 is connected to the front end of the resistor R510, and the rear end of the resistor R510 outputs the regulated voltage signal;

[0128] The two zero-adjust bias terminals of the operational amplifier U9 are connected to the two ends of the adjustable resistor VR1. The sliding terminal of the adjustable resistor VR1 is connected in series with the resistor R509 and then connected to the -12V power supply terminal.

[0129] like Figure 6 As shown, the steady current acquisition circuit mainly includes operational amplifier U10 and operational amplifier U11;

[0130] The front end of the resistor R511 inputs the current signal of the controllable direct current, the rear end of the resistor R511 is connected to the front end of the resistor R512, the rear end of the resistor R512 is connected to the reverse terminal of the operational amplifier U10, the same-direction terminal of the operational amplifier U10 is grounded, and a resistor R513 is connected in parallel between the reverse terminal and the output terminal of the operational amplifier U10, and a capacitor C508 is connected in parallel at both ends of the resistor R513;

[0131] The output end of the operational amplifier U10 is connected to the front end of the resistor R514, the rear end of the resistor R514 is connected in series with the resistor R515 and then grounded, the two ends of the resistor R514 are connected in parallel with the two ends of the adjustable resistor VR4, the sliding end of the adjustable resistor VR4 is connected to the same direction end of the operational amplifier U11, and the reverse direction end of the operational amplifier U11 is connected in series with the resistor R516 and then grounded;

[0132] A resistor R517 is connected in parallel between the reverse terminal and the output terminal of the operational amplifier U11, and a capacitor C512 is connected in parallel across both ends of the resistor R517; the output terminal of the operational amplifier U11 is connected to the front end of the resistor R519, and the rear end of the resistor R519 outputs the regulated voltage signal;

[0133] The two zero-adjust bias terminals of the operational amplifier U11 are connected to the two ends of the adjustable resistor VR3. The sliding terminal of the adjustable resistor VR3 is connected in series with the resistor R512 and then connected to the -12V power supply terminal.

[0134] like Figure 7 As shown, the selection circuit mainly includes an operational amplifier U15C and a selection chip U16;

[0135] The L5V power supply end is connected to the front end of resistor R703, the rear end of resistor R703 is connected to the same-direction terminal of operational amplifier U15C, the +12V power supply end is connected to the cathode of diode D703, the anode of diode D703 is connected to the cathode of diode D704, and the anode of diode D704 is grounded; the common end of diode D703 and diode D704 is connected to the front end of resistor R704, the front end of resistor R704 also inputs the selection signal, the rear end of resistor R704 is connected to the reverse terminal of operational amplifier U15C, and resistor R702 is connected in parallel between the cathode and anode of diode D703;

[0136] The output end of the operational amplifier U15C is connected to the positive electrode of the light-emitting diode ED4, and the negative electrode of the light-emitting diode ED4 is connected in series with the resistor R705 and then grounded;

[0137] The selection chip U16 is a four-way selection chip CD4066; the first input end of the selection chip U16 is connected to the output end of the voltage stabilization acquisition circuit, the second input end of the selection chip U16 is connected to the output end of the current stabilization acquisition circuit, and the first output end and the second output end of the selection chip U16 are connected together and connected to the input comparison circuit;

[0138] The +12V power supply terminal is connected to the front end of the resistor R710, the rear end of the resistor R710 is connected to the first control terminal and the third input terminal of the selection chip U16, and the third output terminal of the selection chip is grounded;

[0139] The output end of the operational amplifier U15C is connected to the front end of the resistor R706, and the rear end of the resistor R706 is connected to the second control end and the third control end of the selection chip U16;

[0140] like Figure 8 As shown, the input comparison circuit mainly includes the operational amplifier U5A;

[0141] The reference voltage is input to the front end of resistor R307, the rear end of resistor R307 is connected to the front end of resistor R308, the rear end of resistor R308 is grounded, the common end of resistor R307 and resistor R308 is connected in series with resistor R309 and then connected to the reverse end of operational amplifier U5A, the same-direction end of operational amplifier U5A is connected to the output end of the selection circuit, the output end of operational amplifier U5A is connected to the positive electrode of diode D304, and the negative electrode of diode D304 outputs the voltage-controlled signal.

[0142] In the selection circuit, when the selection signal is low or floating;

[0143] When the selection signal is left floating, after the 12V voltage is divided by the diodes D703 and D704, the voltage at the same-direction terminal of the operational amplifier U15C is less than the voltage at the reverse terminal. The operational amplifier U15C outputs a low level to the second control terminal and the third control terminal of the selection chip U16. The second input terminal and the output terminal of the selection chip U16 are disconnected, the third input terminal and the output terminal of the selection chip U16 are disconnected, the first control terminal of the selection chip U16 is high, the first input terminal and the output terminal of the selection chip U16 are turned on, and the signal of the voltage stabilization acquisition circuit is selected;

[0144] When the selection signal is at a low level, the voltage at the same-direction terminal of the operational amplifier U15C is greater than the voltage at the reverse terminal. The operational amplifier U15C outputs a high level to the second control terminal and the third control terminal of the selection chip U16. The second input terminal and the output terminal of the selection chip U16 are turned on, and the third input terminal and the output terminal of the selection chip U16 are turned on, pulling the first control terminal of the selection chip U16 to a low level, thereby disconnecting the first input terminal and the output terminal of the selection chip U16, and selecting the signal of the steady current acquisition circuit.

[0145] like Figure 6 As shown, the selection circuit also includes an operational amplifier U15D;

[0146] The first control terminal of the selection chip U16 is also connected to the front end of the capacitor C705, the rear end of the capacitor C705 is connected in series with the resistor R709 and then grounded, and the rear end of the capacitor C705 is connected to the positive electrode of the diode D706;

[0147] The second control end of the selection chip U16 is also connected to the front end of the capacitor C704, the rear end of the capacitor C704 is connected in series with a resistor R707 and then grounded, and the rear end of the capacitor C704 is connected to the positive electrode of the diode D705; the cathode of the diode D705 is connected to the cathode of the diode D706, the common end of the diode D705 and the diode D706 is connected in series with a resistor R708 and then grounded, the common end of the diode D705 and the diode D706 is connected to the same direction end of the operational amplifier U15D, the +12V power supply end is connected to the front end of the resistor R701, the rear end of the resistor R701 is connected in series with a reverse voltage zener diode D701 and then grounded, the common end of the resistor R701 and the voltage zener diode D701 is connected to the reverse end of the operational amplifier U15D, the output end of the operational amplifier U15 is connected to the front end of the diode D702, and the rear end of the diode D706 outputs a switching signal;

[0148] like Figure 7 As shown, the input comparison circuit also includes a selection chip U20,

[0149] The positive electrode of the diode D904 inputs the switching signal, the negative electrode of the diode D904 is connected to the ground after being connected to the resistor R914, the negative electrode of the diode D904 is connected to the control end of the selection chip U20, the input end of the selection chip U20 is connected to the front end of the resistor R318, the front end of the resistor R915, the back end of the resistor R915 is connected to the input end of the selection chip U20, the output end of the selection chip U20 is grounded, and the resistance of the resistor R915 is 5Ω.

[0150] During the switching process of selecting the voltage-stabilized signal or the current-stabilized signal, a switching signal is generated, and the switching signal is used to pull the reverse end of the operational amplifier U5A of the input comparison circuit to a low level, thereby ensuring that the duty cycle of the pulse width drive signal is zero during the switching process, thereby avoiding circuit failure during the switching process.

[0151] like Figure 6 and Figure 3 As shown, the +V2 terminal of the pulse width modulation chip U4 also obtains the switching signal output by the selection circuit.

[0152] The duty cycle of the pulse width drive signal is controlled to be zero by switching the signal, thereby avoiding circuit failure during the switching process.

[0153] Figure 5 and Figure 6 The voltage signal and current signal of the controllable DC power are collected respectively. Figure 7 After choosing one of the two, Figure 8 The same-direction terminal of the input comparison circuit of the op amp U5A, the reverse terminal of the op amp U5A inputs the reference voltage, and the output terminal of the op amp U5A outputs the voltage control signal to Figure 3 The pulse width modulation circuit in; Figure 3 The E1 and E2 terminals of the pulse width modulation circuit output two sets of complementary pulse width control signals with dead zones to Figure 4 Pulse width drive circuit in; Select Figure 4 The first and second pins of the middle group JP1 drive Figure 2 IGBT1 and IGBT4, Figure 2 The current on the primary side of the transformer flows in the forward direction, or select Figure 4 The third and fourth pins of the mid-range group JP1 drive Figure 2 IGBT2 and IGBT3, Figure 2 The current on the primary side of the transformer flows in the reverse direction;

[0154] Figure 7 When the selection is switched, a switching signal is generated. Figure 8 The reverse end of the op amp U5A is pulled down to 0V, so that the duty cycle of the pulse width drive signal is zero during the switching process; at the same time, the switching signal is directly given to Figure 3 The +V2 terminal of the pulse width modulation chip U4 directly controls the duty cycle of the pulse width drive signal to zero.

[0155] Finally, it should be noted that the above examples are only specific implementation examples of the present invention. Of course, those skilled in the art can make changes and modifications to the present invention. If these modifications and modifications fall within the scope of the claims of the present invention and their equivalent technologies, they should be considered to be within the scope of protection of the present invention.

Claims

1. A pulse power supply with a voltage and current stabilization switching function, comprising a rectifier and inverter circuit and a chopper circuit. The rectifier and inverter circuit inputs industrial frequency alternating current and outputs controllable direct current, while the chopper circuit inputs controllable direct current and outputs pulse power. The inverter control circuit also includes an inverter control circuit, which inputs a voltage control signal and outputs a pulse width drive signal to the rectifier inverter circuit, controls the duty cycle of the pulse width drive signal according to the voltage control signal, and further controls the voltage and current of the controllable direct current; Its characteristics are: It also includes a voltage stabilization acquisition circuit, a current stabilization acquisition circuit, a selection circuit and an input comparison circuit; The voltage stabilization acquisition circuit is used to: collect the voltage signal of the controllable direct current and output the stabilization signal to the selection circuit; The steady current acquisition circuit is used to: collect the current signal of the controllable direct current and output the steady current signal to the selection circuit; The selection circuit is used to select a voltage stabilization signal or a current stabilization signal according to a selection signal and output it to the input comparison circuit; The input comparison circuit is used to output a voltage control signal to the inverter control circuit according to the selected voltage stabilization signal or current stabilization signal and the reference voltage, thereby controlling the duty cycle of the pulse width drive signal to achieve voltage stabilization or current stabilization function.

2. The pulse power supply with voltage and current stabilization switching function according to claim 1 is characterized in that: The voltage stabilization acquisition circuit mainly includes an operational amplifier U9; The front end of the resistor R501 inputs the voltage signal of the controllable direct current, the rear end of the resistor R501 is connected to the front end of the adjustable resistor VR2, the rear end of the adjustable resistor VR2 is connected in series with a resistor R502 and then grounded, the sliding end of the adjustable resistor VR2 is connected to the front end of the resistor R503, the rear end of the resistor R503 is connected in series with a resistor R504 and then grounded, and the common end of the resistor R503 and the resistor R504 is connected in series with a resistor R506 and then connected to the same-direction end of the operational amplifier U9; The reverse end of the operational amplifier U9 is connected in series with a resistor R507 and then grounded; between the output end and the reverse end of the operational amplifier U9, a resistor R508 and a capacitor C503 are connected in parallel; the output end of the operational amplifier U9 is connected to the front end of the resistor R510, and the rear end of the resistor R510 outputs the regulated voltage signal; The two zero-adjust bias terminals of the operational amplifier U9 are connected to the two ends of the adjustable resistor VR1. The sliding terminal of the adjustable resistor VR1 is connected in series with the resistor R509 and then connected to the -12V power supply terminal. The steady current acquisition circuit mainly includes an operational amplifier U10 and an operational amplifier U11; The front end of the resistor R511 inputs the current signal of the controllable direct current, the rear end of the resistor R511 is connected to the front end of the resistor R512, the rear end of the resistor R512 is connected to the reverse terminal of the operational amplifier U10, the same-direction terminal of the operational amplifier U10 is grounded, and a resistor R513 is connected in parallel between the reverse terminal and the output terminal of the operational amplifier U10, and a capacitor C508 is connected in parallel at both ends of the resistor R513; The output end of the operational amplifier U10 is connected to the front end of the resistor R514, the rear end of the resistor R514 is connected in series with the resistor R515 and then grounded, the two ends of the resistor R514 are connected in parallel with the two ends of the adjustable resistor VR4, the sliding end of the adjustable resistor VR4 is connected to the same direction end of the operational amplifier U11, and the reverse direction end of the operational amplifier U11 is connected in series with the resistor R516 and then grounded; A resistor R517 is connected in parallel between the reverse terminal and the output terminal of the operational amplifier U11, and a capacitor C512 is connected in parallel across both ends of the resistor R517; the output terminal of the operational amplifier U11 is connected to the front end of the resistor R519, and the rear end of the resistor R519 outputs the regulated voltage signal; The two zero-adjust bias terminals of the operational amplifier U11 are connected to the two ends of the adjustable resistor VR3. The sliding terminal of the adjustable resistor VR3 is connected in series with the resistor R512 and then connected to the -12V power supply terminal. The selection circuit mainly includes an operational amplifier U15C and a selection chip U16; The L5V power supply end is connected to the front end of resistor R703, the rear end of resistor R703 is connected to the same-direction terminal of operational amplifier U15C, the +12V power supply end is connected to the cathode of diode D703, the anode of diode D703 is connected to the cathode of diode D704, and the anode of diode D704 is grounded; the common end of diode D703 and diode D704 is connected to the front end of resistor R704, the front end of resistor R704 also inputs the selection signal, the rear end of resistor R704 is connected to the reverse terminal of operational amplifier U15C, and resistor R702 is connected in parallel between the cathode and anode of diode D703; The output end of the operational amplifier U15C is connected to the positive electrode of the light-emitting diode ED4, and the negative electrode of the light-emitting diode ED4 is connected in series with the resistor R705 and then grounded; The selection chip U16 is a four-way selection chip CD4066; the first input end of the selection chip U16 is connected to the output end of the voltage stabilization acquisition circuit, the second input end of the selection chip U16 is connected to the output end of the current stabilization acquisition circuit, and the first output end and the second output end of the selection chip U16 are connected together and connected to the input comparison circuit; The +12V power supply terminal is connected to the front end of the resistor R710, the rear end of the resistor R710 is connected to the first control terminal and the third input terminal of the selection chip U16, and the third output terminal of the selection chip is grounded; The output end of the operational amplifier U15C is connected to the front end of the resistor R706, and the rear end of the resistor R706 is connected to the second control end and the third control end of the selection chip U16; The input comparison circuit mainly includes an operational amplifier U5A; The reference voltage is input to the front end of resistor R307, the rear end of resistor R307 is connected to the front end of resistor R308, the rear end of resistor R308 is grounded, the common end of resistor R307 and resistor R308 is connected in series with resistor R309 and then connected to the reverse end of operational amplifier U5A, the same-direction end of operational amplifier U5A is connected to the output end of the selection circuit, the output end of operational amplifier U5A is connected to the positive electrode of diode D304, and the negative electrode of diode D304 outputs the voltage-controlled signal.

3. The pulse power supply with voltage and current stabilization switching function according to claim 2 is characterized in that: The selection circuit also includes an operational amplifier U15D; The first control terminal of the selection chip U16 is also connected to the front end of the capacitor C705, the rear end of the capacitor C705 is connected in series with the resistor R709 and then grounded, and the rear end of the capacitor C705 is connected to the positive electrode of the diode D706; The second control end of the selection chip U16 is also connected to the front end of the capacitor C704, the rear end of the capacitor C704 is connected in series with a resistor R707 and then grounded, and the rear end of the capacitor C704 is connected to the positive electrode of the diode D705; the cathode of the diode D705 is connected to the cathode of the diode D706, the common end of the diode D705 and the diode D706 is connected in series with a resistor R708 and then grounded, the common end of the diode D705 and the diode D706 is connected to the same direction end of the operational amplifier U15D, the +12V power supply end is connected to the front end of the resistor R701, the rear end of the resistor R701 is connected in series with a reverse voltage zener diode D701 and then grounded, the common end of the resistor R701 and the voltage zener diode D701 is connected to the reverse end of the operational amplifier U15D, the output end of the operational amplifier U15 is connected to the front end of the diode D702, and the rear end of the diode D706 outputs a switching signal; The input comparison circuit also includes a selection chip U20, The positive electrode of the diode D904 inputs the switching signal, the negative electrode of the diode D904 is connected to the ground after being connected to the resistor R914, the negative electrode of the diode D904 is connected to the control end of the selection chip U20, the input end of the selection chip U20 is connected to the front end of the resistor R318, the front end of the resistor R915, the back end of the resistor R915 is connected to the input end of the selection chip U20, the output end of the selection chip U20 is grounded, and the resistance of the resistor R915 is 5Ω.

4. The pulse power supply with voltage and current stabilization switching function according to claim 3 is characterized in that: The inverter control circuit also obtains the switching signal and directly controls the duty cycle of the pulse width drive signal output by the inverter control circuit to be zero.

5. The pulse power supply with voltage and current stabilization switching function according to claim 3 is characterized in that: The inverter control circuit includes a pulse width modulation circuit and a pulse width drive circuit; After the pulse width modulation circuit inputs the voltage control signal, it outputs a pulse width control signal; after the inverter drive circuit inputs the pulse width control signal, it outputs a pulse width drive signal; The pulse width modulation circuit is used to: control the duty cycle of the pulse width control signal according to the voltage control signal; The pulse width drive circuit is used to: isolate and improve the driving capability of the pulse width drive signal.

6. The pulse power supply with voltage and current stabilization switching function according to claim 5, characterized in that: The pulse width modulation circuit includes a pulse width modulation chip U4, and the model of the pulse width modulation chip U4 is SW494; The +V1 terminal of the pulse width modulation chip U4 is connected to a resistor R302 in series and then to ground. The +V2 terminal of the pulse width modulation chip U4 is connected to a resistor R301 in series and then to ground. The -V1 terminal and -V2 terminal of the pulse width modulation chip U4 are connected to a resistor R303 in series and then to ground. The voltage control signal is input to the +V1 terminal or the +V2 terminal of the pulse width modulation chip U4. The E1 and E2 terminals of the pulse width modulation chip U4 output two sets of pulse width control signals with complementary dead zones; The E1 terminal of the pulse width modulation chip U4 is connected to the anode of the diode D301, the E2 terminal of the pulse width modulation chip U4 is connected to the anode of the diode D302, the cathode of the diode D301 is connected to the cathode of the diode D302, the common terminal of the diode D301 and the diode D302 is connected in series with a resistor R313 and then grounded, the common terminal of the diode D301 and the diode D302 is connected to the first pin of the terminal group JP7, and the third pin of the terminal group JP7 is grounded; Short-circuit the first and third pins of terminal group JP7 to ground the E1 and E2 terminals of the pulse width modulation chip U4, forcing the duty cycle to zero.

7. The pulse power supply with voltage and current stabilization switching function according to claim 6, characterized in that: The -V1 and -V2 terminals of the pulse width modulation chip U4 are connected in series with capacitors C304 and then grounded; the +V1 terminal of the pulse width modulation chip U4 is connected in series with capacitors C303 and then grounded; the +V2 terminal of the pulse width modulation chip U4 is connected in series with capacitors C301 and then grounded; the +V2 terminal of the pulse width modulation chip U4 is connected in series with capacitors C302 and then grounded.

8. The pulse power supply with voltage and current stabilization switching function according to claim 5, characterized in that: The pulse width driving circuit includes an optical coupling isolation chip U1; The E1 terminal of the pulse width modulation chip U4 is connected to the front end of the resistor R103, the rear end of the resistor R103 is connected to the positive input terminal of the optocoupler isolation chip U1, and the negative input terminal of the optocoupler isolation chip U1 is grounded; The output end of the optocoupler isolation chip U1 is connected to the base of the NPN transistor Q1 and the PNP transistor Q2, the +20V power supply end is connected to the collector of the transistor Q1, the emitter of the transistor Q1 is connected to the emitter collector of the transistor Q2, and the collector of the transistor Q2 is grounded; the common end of the transistor Q1 and the transistor Q2 outputs the pulse width drive signal.

9. The pulse power supply with voltage and current stabilization switching function according to claim 8, characterized in that: The +20V power supply terminal is connected to the front end of the resistor R101, the rear end of the resistor R101 is connected in series with a reverse voltage zener diode D101 and then grounded, and the common end of the resistor R101 and the voltage zener diode D101 is connected to the second pin of the terminal group JP1; The common end of the transistor Q1 and the transistor Q2 is connected to the front end of the resistor R107, the rear end of the resistor R107 is connected to the front end of the resistor R108, and the rear end of the resistor R108 is connected to the second pin of the terminal group JP1; the common end of the resistor R107 and the resistor R108 is connected to the first pin of the terminal group JP1; A bidirectional voltage regulator diode DW1 is connected in series between the first and second pins of the terminal group JP1; When the transistor Q1 is turned on, a positive voltage is applied between the first pin and the second pin of the terminal group JP1; when the transistor Q2 is turned on, a negative voltage is applied between the first pin and the second pin of the terminal group JP1; The first pin and the second pin of the terminal group JP1 output a group of pulse width driving signals.

10. The pulse power supply with voltage and current stabilization switching function according to claim 9, characterized in that: The collector series capacitor C101 of the transistor Q1 is connected to the collector of the transistor Q2; the collector series capacitor C102 of the transistor Q1 is connected to the collector of the transistor Q2; the reverse voltage zener diode D101 is connected in parallel with the capacitor C103; the reverse voltage zener diode D101 is connected in parallel with the capacitor C104.

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