CN115065342A

CN115065342A - Program-controlled pulse voltage generating device based on Marx generation principle

Info

Publication number: CN115065342A
Application number: CN202210834911.9A
Authority: CN
Inventors: 赵昭; 高子兴; 李洁
Original assignee: China Electronics Standardization Institute
Current assignee: China Electronics Standardization Institute
Priority date: 2022-07-15
Filing date: 2022-07-15
Publication date: 2022-09-16

Abstract

The embodiment of the invention discloses a program-controlled pulse voltage generating device based on a Marx generating principle, and relates to the technical field of voltage generating devices. The program-controlled pulse voltage generating device comprises a core control unit, a program-controlled charging unit and a Marx pulse voltage generating unit, wherein the core control unit comprises a single chip microcomputer; the program-controlled charging unit comprises a power supply rectifying circuit, a high-frequency transformer circuit, a power supply management circuit and a voltage output circuit; the Marx pulse voltage generating unit comprises a Marx generating circuit and a driving circuit, and the Marx generating circuit does not adopt a boosting inductor. The embodiment of the invention can solve the problem that the amplitude and the width of the pulse voltage cannot be simultaneously controlled by the output pulse voltage.

Description

Program-controlled pulse voltage generating device based on Marx generation principle

Technical Field

The invention relates to the technical field of voltage generation devices, in particular to a program-controlled pulse voltage generation device based on a Marx generation principle.

Background

With the development of power semiconductor technology in recent years, gas switches in the traditional Marx circuit are gradually replaced by solid-state switches to realize high repetition frequency and high reliability pulse design. In order to improve the efficiency of the Marx generator, an inductor and a diode are used for replacing a charging resistor, and the energy storage function of the inductor is utilized to realize the boosting charging of the energy storage capacitor by controlling the on-off time and frequency of the solid-state switch. When the solid-state switch is turned off, the energy storage capacitor is in a parallel state, the electric energy stored by the inductor and the power supply charge the energy storage capacitor through the diode at the same time, and the charging voltage is higher than the power supply voltage at the moment, so that the energy storage capacitor is boosted and charged; when the solid-state switch is turned on, the energy storage capacitors are connected in series to discharge to the load, and the voltage amplitude of the energy storage capacitors is equal to n times of the voltage value of the energy storage capacitors (n is the number of the energy storage capacitors).

In the scheme, the solid-state switch is in a continuous on-off state, so that countless repeated pulses can be applied to two ends of the load, and the solid-state switch cannot be applied to occasions requiring single pulse voltage; in practical operation, the switching frequency of the solid-state switch is generally fixed, and the charging voltage of the energy storage capacitor depends on the switching time of the solid-state switch. If pulse voltages with different amplitudes are obtained, the on-off time of the solid-state switch needs to be changed continuously, so that the width of the pulse voltage applied to the two ends of the load is also changed. Therefore, if a fixed pulse voltage amplitude is desired, a fixed pulse voltage width cannot be obtained; a fixed pulse voltage amplitude cannot be obtained if a fixed pulse voltage width is desired.

Disclosure of Invention

In view of this, embodiments of the present invention provide a program-controlled pulse voltage generating device based on a Marx generation principle, so as to solve a problem that an output pulse voltage cannot control an amplitude and a width of the pulse voltage at the same time.

The utility model provides a programme-controlled pulse voltage generating device based on Marx principle of taking place, includes power supply unit, core control unit, programme-controlled charging unit and Marx pulse voltage generating unit, wherein:

the power supply unit is used for converting alternating current into stable direct current to supply power to the whole device;

the core control unit comprises a singlechip;

the program-controlled charging unit comprises a power supply rectifying circuit, a high-frequency transformer circuit, a power supply management circuit and a voltage output circuit;

the Marx pulse voltage generating unit comprises a Marx generating circuit and a driving circuit, and the Marx generating circuit does not adopt a boost inductor;

the power supply rectifying circuit is used for converting alternating current into stable direct current and supplying the stable direct current to the high-frequency transformer circuit; the power management circuit comprises a pulse width modulation chip and is used for receiving voltage data provided by the single chip microcomputer and outputting pulse signals to the high-frequency transformer circuit; the high-frequency transformer circuit adopts a flyback power supply principle, stores electric energy in a high-frequency transformer in the high-frequency transformer circuit according to the output frequency and the duty ratio of a pulse signal output by the power management circuit, and provides the electric energy to the Marx generation circuit through the voltage output circuit; and the driving circuit receives a control signal of the singlechip to control the on-off time of a solid-state switch in the Marx generating circuit.

Further, the power supply unit includes transformers L connected in sequence ₁ Rectifier bridge D ₁ And a plurality of power supply voltage stabilizing modules U ₁ ～U ₄ 。

Further, the power supply rectifying circuit comprises a first output end and a second output end, and a first filter capacitor C is connected in series between the first output end and the second output end ₁₃ And a second filter capacitor C ₁₄ And a first equalizing resistor R is also connected in series ₁ And a second voltage equalizing resistor R ₂ Said first filter capacitor C ₁₃ And a first voltage equalizing resistor R ₁ Connected in parallel, the second filter capacitor C ₁₄ And a second voltage equalizing resistor R ₂ Are connected in parallel.

Furthermore, the power supply rectifying circuit passes through an X safety capacitorCX ₁ 、CX ₃ Y-type capacitor CY ₁ 、CY ₂ Common mode inductor L ₂ Filtering together, and passing through a rectifier bridge D ₂ Rectified and finally passes through the first filter capacitor C ₁₃ A second filter capacitor C ₁₄ A first voltage equalizing resistor R ₁ And a second voltage equalizing resistor R ₂ To obtain stable direct current.

Further, the high frequency transformer circuit includes a first transformer L ₅ A second transformer L ₃ A first NPN transistor Q ₁ A second NPN transistor Q ₂ A third NPN transistor Q ₃ And a fourth NPN transistor Q ₄ ；

The pulse width modulation chip comprises a first pulse signal output end and a second pulse signal output end, and the first pulse signal output end is connected with the fourth NPN transistor Q ₄ The second pulse signal output end is connected with the third NPN transistor Q ₃ The base electrode of (1);

DC power supply through protective resistor R ₁₂ The rear part is divided into three paths, and one path is connected with the fourth NPN transistor Q ₄ Said fourth NPN transistor Q ₄ The emitter of (2) is grounded; the other path is connected with the first transformer L ₅ The first transformer L, the intermediate lead of the primary winding of ₅ The leads at the two ends of the primary winding are respectively connected with the third NPN transistor Q ₃ Collector of (a) and a fourth NPN transistor Q ₄ A collector electrode of (a); the last path is connected with the third NPN transistor Q ₃ The base of said third NPN transistor Q ₃ The emitter of (2) is grounded;

the first output end of the power supply rectifying circuit is connected with the first NPN transistor Q ₁ The first NPN transistor Q ₁ Is connected to the second NPN transistor Q ₂ The second NPN transistor Q ₂ The emitter of the power supply rectifying circuit is connected with the second output end of the power supply rectifying circuit;

the first transformer L ₅ The secondary winding comprises a first secondary winding and a second secondary winding, one end of the first primary winding is led out through a second terminalPolar tube D ₄ And a protective resistor R ₆ Post-connecting the second NPN transistor Q ₂ And the other end of the base is connected with the second NPN transistor Q through a lead wire ₂ An emitter of (1); the second primary winding has three-terminal leads, one of which is connected to the second transformer L ₃ Is connected to said first filter capacitor C ₁₃ And a second filter capacitor C ₁₄ Between, the lead wire at the other end passes through a diode D ₃ And a protective resistor R ₃ Post-connecting the first NPN transistor Q ₁ With the intermediate lead connected to the first NPN transistor Q ₁ An emitter of (1);

the voltage output circuit is used for the second transformer L ₃ The output of the secondary winding of (a) is rectified and filtered and then provided to the Marx generation circuit.

Further, the first pulse signal output by the first pulse signal output terminal and the second pulse signal output by the second pulse signal output terminal are a pair of complementary pulse signals;

and/or the second transformer L ₃ The two ends of the primary winding are connected with a resistor R in parallel ₉ And a capacitor C ₁₈ 。

Further, the pulse width modulation chip includes an output voltage collecting end for collecting an output voltage between two output ends of the voltage output circuit and a reference voltage receiving end for obtaining a reference voltage from the single chip microcomputer, and the pulse width modulation chip compares the obtained output voltage with the reference voltage to adjust a duty ratio of the output pulse signal.

Furthermore, the power management circuit further comprises a digital-to-analog conversion chip, wherein an input end of the digital-to-analog conversion chip is connected to the single chip microcomputer, and an output end of the digital-to-analog conversion chip is connected to the pulse width modulation chip so as to provide reference voltage for the pulse width modulation chip.

Further, in the voltage output circuit, the second transformer L ₃ The secondary winding passes through a rectifier bridge D in sequence ₇ Energy storage inductor L ₄ Filter capacitor C ₁₉ ～C ₂₂ The output is then provided to the Marx generating circuit;

and/or two divider resistors R are connected in series between two output ends of the voltage output circuit ₁₀ 、R ₁₁ And a connection point between the two divider resistors is connected to an output voltage acquisition end of the pulse width modulation chip.

Further, the driving circuit comprises a control switch U ₅ The control switch U ₅ The control end of the control switch is connected with the control signal output end of the singlechip, and the control switch U ₅ A plurality of photoelectric couplers U connected in series ₆ ～U ₉ A plurality of photoelectric couplers U ₆ ～U ₉ Respectively controlling a solid-state switch Q in the Marx generating circuit ₅ ～Q ₈ The control switch U ₅ Is a photoelectric coupler, and the solid-state switch Q in the Marx generating circuit ₅ ～Q ₈ Are both NPN transistors.

According to the program-controlled pulse voltage generating device based on the Marx generation principle, on one hand, a power supply management circuit comprises a pulse width modulation chip, the power supply management circuit is used for receiving voltage data provided by a single chip microcomputer and outputting pulse signals to a high-frequency transformer circuit, the high-frequency transformer circuit adopts a flyback power supply principle, electric energy is stored in a high-frequency transformer in the high-frequency transformer circuit according to the output frequency and the duty ratio of the pulse signals output by the power supply management circuit, and the electric energy is supplied to the Marx generation circuit through a voltage output circuit, so that the power supply management circuit can adjust the duty ratio of the output pulse signals by means of the pulse width modulation chip, the energy storage time of the high-frequency transformer is adjusted, the amplitude of the output voltage is adjusted, and the purpose of controlling the amplitude of the pulse voltage is achieved; on the other hand, the Marx generating circuit does not adopt a boost inductor, so that the circuit per se loses the function of boosting by controlling the on-off of the solid-state switch, and just as the circuit receives the control signal of the single chip microcomputer to control the on-off time of the solid-state switch in the Marx generating circuit, so that the output pulse width depends on the on-off time of the solid-state switch, and the purpose of controlling the pulse voltage width is achieved. Therefore, the embodiment of the invention is obtained by improving on the basis of the Marx generation principle, and can solve the problem that the amplitude and the width of the output pulse voltage cannot be controlled simultaneously, so that the aim of directly controlling the amplitude and the width of the output pulse voltage by an upper computer is fulfilled.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a circuit diagram of a power supply unit according to the present invention;

FIG. 2 is a circuit diagram of a core control unit according to the present invention;

FIG. 3 is a circuit diagram of the programmable charging unit of the present invention;

fig. 4 is a circuit diagram of a driving circuit of the Marx pulse voltage generating unit in the present invention;

fig. 5 is a circuit diagram of a Marx generation circuit of the Marx pulse voltage generation unit of the present invention.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

It should be understood that the described embodiments are only some embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The embodiment of the invention provides a program-controlled pulse voltage generating device based on a Marx generation principle, which comprises a core control unit 11, a program-controlled charging unit 12 and a Marx pulse voltage generating unit 13, as shown in FIGS. 1 to 5, wherein:

the core control unit 11 comprises a single chip microcomputer which can be of various types, and in the embodiment shown in the figure, the single chip microcomputer is an STM32 single chip microcomputer; the single chip microcomputer can carry out data transmission with an upper computer in a serial port communication mode and complete data transmission with related units by an SPI (serial peripheral interface) communication protocol;

the program-controlled charging unit 12 comprises a power supply rectifying circuit 121, a high-frequency transformer circuit 122, a power supply management circuit 123 and a voltage output circuit 124;

the Marx pulse voltage generating unit 13 comprises a Marx generating circuit 131 and a driving circuit 132, wherein the Marx generating circuit 131 does not adopt a boosting inductor;

the power supply rectifying circuit 121 is configured to convert the alternating current into a stable direct current and supply the stable direct current to the high-frequency transformer circuit 122; the power management circuit 123 comprises a pulse width modulation chip, and the power management circuit 123 is used for receiving voltage data provided by the single chip microcomputer and outputting a pulse signal to the high-frequency transformer circuit 122; the high-frequency transformer circuit 122 stores electric energy in a high-frequency transformer in the high-frequency transformer circuit 122 according to the output frequency and duty ratio of the pulse signal output from the power management circuit 123 by using a flyback power supply principle, and supplies the electric energy to the Marx generation circuit 131 through the voltage output circuit 124; the driving circuit 132 receives a control signal of the single chip microcomputer to control the on-off time of the solid-state switch in the Marx generating circuit 131.

According to the program-controlled pulse voltage generating device based on the Marx generation principle, on one hand, a power supply management circuit comprises a pulse width modulation chip, the power supply management circuit is used for receiving voltage data provided by a single chip microcomputer and outputting pulse signals to a high-frequency transformer circuit, the high-frequency transformer circuit adopts a flyback power supply principle, electric energy is stored in a high-frequency transformer in the high-frequency transformer circuit according to the output frequency and the duty ratio of the pulse signals output by the power supply management circuit, and the electric energy is supplied to the Marx generation circuit through a voltage output circuit, so that the power supply management circuit can adjust the duty ratio of the output pulse signals by means of the pulse width modulation chip, the energy storage time of the high-frequency transformer is adjusted, the amplitude of the output voltage is adjusted, and the purpose of controlling the amplitude of the pulse voltage is achieved; on the other hand, the Marx generating circuit does not adopt a boost inductor, so that the circuit per se loses the function of boosting by controlling the on-off of the solid-state switch, and just as the Marx generating circuit receives the control signal of the single chip microcomputer to control the on-off time of the solid-state switch in the Marx generating circuit, so that the output pulse width depends on the on-off time of the solid-state switch, and the purpose of controlling the pulse voltage width is achieved. Therefore, the embodiment of the invention is obtained by improving on the basis of the Marx generation principle, and can solve the problem that the amplitude and the width of the output pulse voltage cannot be controlled simultaneously, so that the aim of directly controlling the amplitude and the width of the output pulse voltage by an upper computer is fulfilled.

Power supply unit

Considering that there are many different chips in the circuit and the power supply voltage is different, in order to facilitate power supply, a power supply unit 10 may be provided for converting the alternating current into the stable direct current to supply power to the whole device.

The power supply unit 10 may employ various designs in the art. For example, fig. 1 shows a circuit diagram of an embodiment of a power supply unit 10, whose main function is to supply power to the entire system. 220V commercial power passes through a transformer L ₁ Rectifier bridge D ₁ Converted into required direct current voltage and then passes through a power supply voltage stabilizing module U ₁ 、U ₂ 、U ₃ 、U ₄ And converting into a required voltage value. Wherein U is ₁ For supplying +12V DC power, U ₂ For supplying +5V DC power, U ₃ For supplying +3.3V DC power, U ₄ The direct current power supply is used for supplying +2.048V direct current power supply; the number of the power supply voltage stabilizing modules can be flexibly designed according to needs, is not limited to 4 shown in the figure, and can be more or less. For filtering and voltage-stabilizing, the figure shows a rectifier bridge D ₁ The output end of each power supply voltage stabilizing module is also provided with a capacitor C ₁ ～C ₁₀ 。

Core control unit

Fig. 2 shows a circuit diagram of an embodiment of the core control unit 11. The unit is a core control part of the program control pulse voltage generating device based on the Marx generation principle, consists of an STM32 single chip microcomputer and a crystal oscillator, and mainly has the functions of processing received pulse amplitude and pulse width data and then controlling capacitor parallel charging voltage and capacitor serial discharging time. The PA9 and the PA10 are respectively connected with a serial port TX and a serial port RX, and play a role in data transmission with an upper computer (not shown); PB0, PB1, and PB2 are connected to DIN, SCLK, and CS pins of a digital-to-analog DA conversion chip (TLC5618 chip) of the program-controlled charging unit 12, and provide digital quantity data thereto. PB3 and PB4 are pulse width output control pins and charging voltage feedback pins.

Program-controlled charging unit

Fig. 3 is a circuit diagram of an embodiment of the programmable charging unit 12. The part is based on the basic principle of a flyback power supply, and voltage program control and stable output are realized by combining the voltage comparison function of

pins

1 and 2 of a pulse width modulation chip (TL494 power supply management chip). The power supply circuit mainly comprises a power supply rectifying circuit 121, a high-frequency transformer circuit 122, a power supply management circuit 123 and a voltage output circuit 124.

The working principle is as follows: when the core control unit 11 transmits the preset voltage value digital quantity data to the program-controlled charging unit 12 through the SPI communication protocol, a digital-to-analog conversion chip (TLC5618 chip) of the program-controlled charging unit 12 converts the digital quantity into a voltage value as a reference voltage of a pulse width modulation chip (TL494 chip), and the pulse width modulation chip outputs a pulse signal with dead time to control the high-frequency transformer to operate, so that voltage is output on a secondary winding of the high-frequency transformer, and then the pulse width modulation chip compares the acquired output voltage value with the reference voltage to adjust a duty ratio of the output pulse signal, so that energy storage time of the high-frequency transformer is adjusted, and further amplitude of the output voltage is adjusted, and the output voltage is more stable.

(1) Power supply rectifying circuit

The power rectifying circuit 121 is for converting an alternating current into a stable direct current to be supplied to the high frequency transformer circuit 122, and may adopt various designs as will be apparent to those skilled in the art.

As shown in fig. 3, in the output portion, the power supply rectification circuit 121 preferably includes a first output terminal and a second output terminal, and a first filter capacitor C is connected in series between the first output terminal and the second output terminal ₁₃ And a second filter capacitor C ₁₄ And a first equalizing resistor R is also connected in series ₁ And a second equalizing resistor R ₂ First filter capacitor C ₁₃ And a first voltage equalizing resistor R ₁ Connected in parallel, a second filter capacitor C ₁₄ And a second voltage equalizing resistor R ₂ Are connected in parallel.

In specific implementation, the power rectification circuit 121 passes 220VAC through an X safety capacitor CX ₁ And CX ₃ Y safety capacitor CY ₁ And CY ₂ Common mode inductor L ₂ Filtering together, and passing through a rectifier bridge D ₂ Rectifying, and filtering with a filter capacitor C ₁₃ And C ₁₄ Voltage equalizing resistor R ₁ And R ₂ To obtain stable direct current.

(2) High-frequency voltage device circuit

The high-frequency transformer circuit 122 functions to store electric energy in the high-frequency transformer by the direct current obtained from the power supply rectifying circuit 121 in accordance with the output frequency and duty ratio of the pulse width modulation chip (TL494 chip), and then to output the electric energy in the secondary winding.

The high frequency transformer circuit 122 may take various designs as will be readily apparent to those skilled in the art, and in one embodiment, as shown in FIG. 3, preferably includes a first transformer L ₅ A second transformer L ₃ A first NPN transistor Q ₁ A second NPN transistor Q ₂ A third NPN transistor Q ₃ And a fourth NPN transistor Q ₄ (ii) a Here, a transformer L ₃ 、L ₅ Namely the high-frequency transformer;

the pulse width modulation chip (TL494 chip in the figure) comprises a first pulse signal output end (C1, pin 8) and a second pulse signal output end (C2, pin 11), wherein the first pulse signal output end is connected with a fourth NPN transistor Q ₄ A second pulse signal output terminal is connected with a third NPN transistor Q ₃ A base electrode of (1);

DC power supply +12V via protective resistor R ₁₂ The rear part is divided into three paths, and one path is connected with a fourth NPN transistor Q ₄ Base of (1), fourth NPN transistor Q ₄ Is grounded (for protection, the emitter can be connected via a capacitor C ₂₃ Ground, Q ₄ Base electrode ofR ₁₂ Can be connected in series with a resistor R ₁₅ ) (ii) a The other path is connected with a first transformer L ₅ Of the primary winding of the first transformer L ₅ The leads at the two ends of the primary winding are respectively connected with a third NPN transistor Q ₃ Collector of and a fourth NPN transistor Q ₄ A collector electrode of (a); the last path is connected with a third NPN transistor Q ₃ Base of (2), third NPN transistor Q ₃ Is grounded (for protection, the emitter can be connected via a diode D) ₁₀ Ground, Q ₃ Base and R of ₁₂ Can be connected in series with a resistor R ₁₃ ) (ii) a For protection, Q ₃ And Q ₄ Can be respectively connected with resistors R between the base electrode and the emitter electrode ₁₄ 、R ₁₆ ，Q ₃ And Q ₄ Between the collector and the emitter can be respectively connected with a diode D ₈ 、D ₉ ；

A first output terminal of the power rectification circuit 121 is connected to the first NPN transistor Q ₁ A first NPN transistor Q ₁ Is connected to a second NPN transistor Q ₂ A second NPN transistor Q ₂ Is connected to the second output terminal of the power supply rectification circuit 121; for protection, Q ₁ And Q ₂ Between the collector and the emitter can be respectively connected with a diode D ₅ 、D ₆ ；

First transformer L ₅ The secondary winding comprises a first secondary winding and a second secondary winding, one end lead (pin 5) of the first primary winding passes through a diode D ₄ And a protective resistor R ₆ Rear-connected second NPN transistor Q ₂ Base (for protection, D) ₄ And R ₆ Two ends can be connected with a capacitor C in parallel ₁₇ ，R ₆ And Q ₂ A resistor R can be connected in series between the base electrodes ₇ ) The other end lead (pin 4) is connected with a second NPN transistor Q ₂ An emitter of (1); the second primary winding has three-terminal leads, one of which (pin 3) passes through the second transformer L ₃ Is connected to a first filter capacitor C ₁₃ And a second filter capacitor C ₁₄ Between (for protection, a capacitor C can be connected in series at the same time ₁₅ ) The lead wire (pin 1) at the other end passes through a diode D ₃ And a protective resistor R ₃ Back connected first NPN transistor Q ₁ Base (for protection, D) ₃ And R ₃ Two ends can be connected with a capacitor C in parallel ₁₆ ，R ₃ And Q ₁ Can be connected in series with a resistor R between the base electrodes ₄ ) The middle lead (pin 2) is connected with a first NPN transistor Q ₁ An emitter of (1); for protection, Q ₁ And Q ₂ Can be respectively connected with resistors R between the base electrode and the emitter electrode ₅ 、R ₈ ；

The voltage output circuit 124 is used for the second transformer L ₃ The output of the secondary winding of (a) is rectified and filtered and then supplied to a Marx generation circuit 131.

Here, the circuit operating principle is as follows:

when Q is ₃ Conducting, Q ₄ At the time of cutoff: DC 12V voltage across R ₁₂ 、Q ₃ At the transformer L ₅ Induces an electromotive force on the secondary winding, which passes through D ₃ 、R ₃ 、R ₄ 、R ₅ Make Q ₁ And conducting. At this time, the dc voltage rectified by the power rectifying circuit 121 is converted into the dc voltage from the capacitor C ₁₃ Positive electrode flowing out through Q ₁ 、L ₅ Secondary winding, L ₃ Primary winding current return capacitor C ₁₃ A negative electrode of (1), passing electric energy through L ₃ A secondary winding output;

when Q is ₃ Cutoff, Q ₄ When the circuit is conducted: DC 12V voltage across R ₁₂ 、Q ₄ At the transformer L ₅ Induces an electromotive force, which passes through D ₄ 、R ₆ 、R ₇ 、R ₈ Make Q ₂ And conducting. At the moment, the direct-current voltage rectified by the power supply rectifying circuit is driven by the capacitor C ₁₄ The positive electrode flows out through L ₃ Primary winding, L ₅ Secondary winding, Q ₂ Return capacitance C ₁₄ A negative electrode of (1), passing electric energy through L ₃ And outputting the secondary winding.

A second transformer L ₃ Preferably connected in parallel across the primary winding with a resistor R ₉ And a capacitor C ₁₈ Resistance R ₉ And a capacitor C ₁₈ Has the function of an absorption transformer L ₃ The back-induced electromotive force during current commutation prevents the induced high voltage from damaging components.

(3) Power management circuit

The pwm chip may be a fixed frequency pwm chip, and may be of various types, in the figure, a TL494 chip. The TL494 chip has the function of collecting a voltage-dividing resistor R through a pin 1 ₁₁ And the voltage at the two ends is compared with the reference voltage value of the pin 2, so that the duty ratio of the output pulse of the pin 8 and the pin 11 is changed. That is, the pulse width modulation chip (TL494 chip) includes an output voltage collecting terminal (1IN +, pin 1) for collecting an output voltage between two output terminals of the voltage output circuit 124 and a reference voltage receiving terminal (1IN-, pin 2) for obtaining a reference voltage from the single chip microcomputer, and compares the obtained output voltage with the reference voltage to adjust the duty ratio of the output pulse signal.

To facilitate the collection of the output voltage, two voltage dividing resistors R may be connected in series between the two output terminals of the voltage output circuit 124 ₁₀ 、R ₁₁ And a connection point between the two divider resistors is connected to an output voltage acquisition end (1IN +, pin 1) of a pulse width modulation chip (TL494 chip).

In order to obtain the reference voltage conveniently, the power management circuit 123 further includes a digital-to-analog conversion chip, which may be of various types, in the figure, a TLC5618 chip, an input end of the TLC5618 chip is connected to the single chip, and an output end of the TLC5618 chip is connected to the TL494 chip to provide the reference voltage to the TL494 chip. Specifically, the voltage value at pin 2 of the TL494 chip is provided by the digital-to-analog conversion chip TLC5618 receiving the voltage converted from the data sent by the core control unit 11 in the form of SPI communication protocol, where pins 1, 2, and 3 of the TLC5618 are connected to DIN, SCLK, and CS of the core control unit 11.

After connecting pin 13 and pin 14 of the TL494 chip, the TL494 chip will output in a push-pull manner, that is, pins 8 and 11 will output a pair of complementary pulse signals, that is, the first pulse signal output from the first pulse signal output terminal (C1, pin 8) and the second pulse signal output from the second pulse signal output terminal (C2, pin 11) are preferably a pair of pulse signalsComplementary pulse signals. A capacitor C with pulse frequency externally connected by a pin 5 ₂₆ And a resistor R externally connected with the pin 6 ₂₂ The dead time is determined by the voltage externally connected to pin 4, i.e. the reference 5V voltage output on pin 14 is applied to resistor R ₁₉ Is determined by the partial pressure of (c).

(4) Voltage output circuit

The voltage output circuit 124 may have various designs as will be apparent to those skilled in the art, and in one embodiment, as shown in FIG. 3, the second transformer L ₃ The secondary winding passes through a rectifier bridge D in sequence ₇ Energy storage inductor L ₄ Filter capacitor C ₁₉ ～C ₂₂ The post output is provided to a Marx generation circuit 131.

Marx pulse voltage generating unit

The Marx pulse voltage generating unit 13 is mainly composed of two parts, a Marx generating circuit 131 and a driving circuit 132. The programmable charging unit 12 charges the parallel energy storage capacitor, and when the charging reaches a preset voltage, the driving circuit 132 receives an X signal from the core control unit 11 to control the solid-state switch Q ₅ ～Q ₈ And conducting to enable the energy storage capacitor to output pulse voltage to the load in series, wherein the output pulse width depends on the conducting time of the solid-state switch.

(1) Driving circuit

The driving circuit 132 may be designed in various ways as will be apparent to those skilled in the art, and in one embodiment, as shown in fig. 4, it is mainly composed of an optical coupler isolator and a current limiting resistor.

The driving circuit 132 includes a control switch U ₅ (preferably also a photocoupler), the control switch U ₅ The control end of the control switch is connected with the control signal output end (X signal) of the singlechip and controls the switch U ₅ A plurality of photoelectric couplers U connected in series ₆ ～U ₉ A plurality of photoelectric couplers U ₆ ～U ₉ Respectively controlling a solid-state switch Q in the Marx generation circuit 131 ₅ ～Q ₈ 。

When the optical coupler isolator U ₅ When receiving the high level signal of the core control unit X, the output end is conducted. Then pass throughCurrent limiting resistor R ₂₄ Optocoupler isolator U ₆ 、U ₇ 、U ₈ 、U ₉ Voltage is applied to turn on the output terminal, and 12V DC voltage is output.

(2) Marx generating circuit

Fig. 5 is a circuit diagram of an embodiment of the Marx generation circuit 131, where in this embodiment, n is 4, and n is the number of stages of the Marx generator, and specifically, a value can be flexibly selected according to actual needs. Solid state switch (Q) in Marx generation circuit 131 ₅ ～Q ₈ ) May be all NPN transistors. The Marx generating circuit 131 is an improvement on the prior Marx generator, and the boosting inductance is removed, so that the circuit per se loses the function of switching on and off the boosting by controlling the solid-state switch. Therefore, the programmable charging circuit 12 is adopted to charge the parallel energy storage capacitor, and the function of adjusting the output pulse width is realized.

Before the driving circuit 132 does not receive the X signal of the core control unit 11, the solid-state switch of the Marx generating circuit 131 is in an off state, and the programmable charging unit 12 passes through the diode D ₁₂ ～D ₁₉ 4 groups of energy storage capacitors connected in parallel are charged. When the core control unit 11 detects that the energy storage capacitors are charged completely, a control signal is sent to enable the solid-state switches to be conducted, and 4 groups of energy storage capacitors are connected in series to discharge to the load.

In summary, the technical scheme of the embodiment of the invention realizes that the pulse width is adjustable and the output pulse amplitude is continuously adjustable on the premise of meeting the requirement of the pulse voltage output amplitude. The pulse voltage generating device is simple and convenient to use, and can directly input pulse voltage amplitude and pulse width through the serial port of the upper computer.

The above description is only for the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The utility model provides a programme-controlled pulse voltage generating device based on Marx principle of taking place which characterized in that, includes power supply unit, core control unit, programme-controlled charging unit and Marx pulse voltage generating unit, wherein:

the core control unit comprises a singlechip;

the power supply rectifying circuit is used for converting alternating current into stable direct current and supplying the stable direct current to the high-frequency transformer circuit; the power management circuit comprises a pulse width modulation chip and is used for receiving voltage data provided by the single chip microcomputer and outputting pulse signals to the high-frequency transformer circuit; the high-frequency transformer circuit adopts a flyback power supply principle, stores electric energy in a high-frequency transformer in the high-frequency transformer circuit according to the output frequency and the duty ratio of a pulse signal output by the power management circuit, and provides the electric energy to the Marx generating circuit through the voltage output circuit; and the driving circuit receives a control signal of the singlechip to control the on-off time of a solid-state switch in the Marx generating circuit.

2. Marx generation principle-based program-controlled pulsed voltage generation device according to claim 1, characterized in that the power supply unit comprises successively connected transformers (L) ₁ ) Rectifier bridge (D) ₁ ) And a plurality of power supply voltage stabilizing modules (U) ₁ ～U ₄ )。

3. The Marx generation principle-based program-controlled pulsed voltage generation device according to claim 1, characterized in that the power supply rectification circuit comprises a first output end and a second output end, and a first output end is connected in series between the first output end and the second output endA filter capacitor (C) ₁₃ ) And a second filter capacitor (C) ₁₄ ) And a first voltage-sharing resistor (R) is also connected in series ₁ ) And a second voltage equalizing resistor (R) ₂ ) Said first filter capacitance (C) ₁₃ ) And a first voltage equalizing resistor (R) ₁ ) Connected in parallel, the second filter capacitor (C) ₁₄ ) And a second voltage equalizing resistor (R) ₂ ) Are connected in parallel.

4. Marx-generation-principle-based program-controlled pulse voltage generation device according to claim 3, characterized in that the power rectification circuit passes through an X safety Capacitor (CX) ₁ 、CX ₃ ) Y-type Capacitor (CY) ₁ 、CY ₂ ) Common mode inductor (L) ₂ ) Filtered together and passed through a rectifier bridge (D) ₂ ) Rectified and finally passed through said first filter capacitor (C) ₁₃ ) A second filter capacitor (C) ₁₄ ) A first voltage equalizing resistor (R) ₁ ) And a second voltage equalizing resistor (R) ₂ ) To obtain stable direct current.

5. Marx-generation-principle-based program-controlled pulsed voltage generation device according to claim 3, characterized in that the high-frequency transformer circuit comprises a first transformer (L) ₅ ) A second transformer (L) ₃ ) A first NPN transistor (Q) ₁ ) A second NPN transistor (Q) ₂ ) A third NPN transistor (Q) ₃ ) And a fourth NPN transistor (Q) ₄ )；

The pulse width modulation chip comprises a first pulse signal output end and a second pulse signal output end, and the first pulse signal output end is connected with the fourth NPN transistor (Q) ₄ ) Said second pulse signal output terminal is connected to said third NPN transistor (Q) ₃ ) A base electrode of (1);

DC power supply protected resistor (R) ₁₂ ) The rear part is divided into three paths, and one path is connected with the fourth NPN transistor (Q) ₄ ) Said fourth NPN transistor (Q) ₄ ) The emitter of (2) is grounded; the other path is connected with the first transformer (L) ₅ ) The first transformer (L), the intermediate lead of the primary winding of ₅ ) Of the primary winding ofIs connected to the third NPN transistor (Q) ₃ ) Collector and a fourth NPN transistor (Q) ₄ ) A collector electrode of (a); the last path is connected with the third NPN transistor (Q) ₃ ) The third NPN transistor (Q) ₃ ) The emitter of (2) is grounded;

the first output end of the power supply rectifying circuit is connected with the first NPN transistor (Q) ₁ ) The first NPN transistor (Q) ₁ ) Is connected to the second NPN transistor (Q) ₂ ) The second NPN transistor (Q), a collector of (B), a second NPN transistor (Q), a collector of (B), a second NPN transistor (Q), a source of (B), a drain, and a drain, a transistor (e ₂ ) The emitter of the power supply rectifying circuit is connected with the second output end of the power supply rectifying circuit;

the first transformer (L) ₅ ) Comprises a first secondary winding and a second secondary winding, one end of the first primary winding is led through a diode (D) ₄ ) And a protective resistor (R) ₆ ) Post-connecting the second NPN transistor (Q) ₂ ) And the other end of the base is connected with the second NPN transistor (Q) by a lead wire ₂ ) An emitter of (1); the second primary winding has a three-terminal lead, wherein one terminal lead passes through the second transformer (L) ₃ ) Is connected to said first filter capacitance (C) ₁₃ ) And a second filter capacitor (C) ₁₄ ) Between, the other end leads through a diode (D) ₃ ) And a protective resistor (R) ₃ ) Post-connecting the first NPN transistor (Q) ₁ ) With intermediate lead connected to said first NPN transistor (Q) ₁ ) An emitter of (1);

the voltage output circuit is used for the second transformer (L) ₃ ) The output of the secondary winding of (b) is rectified and filtered and then provided to the Marx generation circuit.

6. The programmable pulse voltage generating device based on the Marx generation principle of claim 5, wherein the first pulse signal output by the first pulse signal output terminal and the second pulse signal output by the second pulse signal output terminal are a pair of complementary pulse signals;

and/or the second transformer (L) ₃ ) Is connected in parallel with a resistor (R) at two ends ₉ ) And a capacitor (C) ₁₈ )。

7. The program-controlled pulse voltage generating device based on the Marx generation principle of claim 5, wherein the pulse width modulation chip comprises an output voltage collecting terminal for collecting the output voltage between the two output terminals of the voltage output circuit and a reference voltage receiving terminal for obtaining the reference voltage from the single chip microcomputer, and the pulse width modulation chip compares the obtained output voltage with the reference voltage to adjust the duty ratio of the output pulse signal.

8. The Marx generation principle-based program-controlled pulse voltage generation device according to claim 7, wherein the power management circuit further comprises a digital-to-analog conversion chip, an input end of the digital-to-analog conversion chip is connected to the single chip microcomputer, and an output end of the digital-to-analog conversion chip is connected to the pulse width modulation chip to provide a reference voltage for the pulse width modulation chip.

9. Marx generation principle-based program-controlled pulsed voltage generation device according to claim 8, characterized in that in the voltage output circuit the second transformer (L) ₃ ) In turn through a rectifier bridge (D) ₇ ) Energy storage inductor (L) ₄ ) Filter capacitor (C) ₁₉ ～C ₂₂ ) The output is then provided to the Marx generating circuit;

and/or two divider resistors (R) are connected in series between two output ends of the voltage output circuit ₁₀ 、R ₁₁ ) And a connection point between the two divider resistors is connected to an output voltage acquisition end of the pulse width modulation chip.

10. Marx-generation-principle-based program-controlled pulsed voltage generation device according to claim 1, characterized in that the drive circuit comprises a control switch (U) ₅ ) Said control switch (U) ₅ ) The control end of the control switch (U) is connected with the control signal output end of the singlechip ₅ ) A plurality of photoelectric couplers (U) connected in series are connected ₆ ～U ₉ ) Said plurality of photo-couplers (U) ₆ ～U ₉ ) Respectively controlling a solid state switch (Q) in said Marx generating circuit ₅ ～Q ₈ ) Said control switch (U) ₅ ) Is a photoelectric coupler, a solid-state switch (Q) in the Marx generating circuit ₅ ～Q ₈ ) Are all NPN transistors.