A high-voltage pulse capacitor charging power supply circuit

Abstract

The utility model relates to nuclear fusion device power supply field, specifically disclose a kind of high-voltage pulse capacitor charging power supply circuit, including the isolation transformer, single-phase full-bridge rectifier circuit, BUCK circuit, push-pull circuit, step-up transformer, voltage doubler rectifier circuit, pulse capacitor, magnet coil connected in turn, the BUCK circuit is connected with voltage doubler rectifier circuit by negative feedback circuit, the negative feedback circuit includes voltage dividing circuit, voltage dividing circuit input end connects voltage doubler rectifier circuit, and output end is connected with following module, sampling module, comparison module, drive circuit in proper order, the utility model has high control precision, transformer volume is small, power supply device volume is small.

Description

Technical Field

[0001] This utility model relates to the field of power supply for nuclear fusion devices, and more specifically to a high-voltage pulse capacitor charging power supply circuit. Background Technology The power supply system is a crucial component of a linear magnetic confinement fusion device. To meet the rapidly changing current requirements of the magnet coils, each power supply must be designed to power one magnet coil. This reduces the load circuit impedance, allowing the load current to change rapidly within nanoseconds. Since a linear fusion device contains hundreds of magnet coils, corresponding to hundreds of power supplies, the power supply design must minimize size and improve the device's portability. Furthermore, the generation and maintenance of plasma in a linear fusion device depend entirely on the precisely changing magnetic field generated by the external magnet coils. Therefore, ultra-high precision current must be generated on the magnet coils to ensure the external magnetic field perfectly matches the requirements. The current generation path in a linear fusion device involves storing voltage in a pulse capacitor and directly outputting it to the magnet coils via switches and circuitry. Given a fixed circuit impedance, generating ultra-high precision current requires the voltage on the pulse capacitors to also achieve ultra-high precision. On the other hand, the pulse capacitor's factory voltage is almost 0. At the beginning of power supply use, the pulse capacitor voltage needs to be stably charged from 0V to the required tens of kV. Therefore, the previous charging power supply must meet this wide range and stable charging process.

[0002] Therefore, how to reduce the size of the charging power supply, meet the requirements of high-precision and stable pulse capacitor voltage, and meet the requirements of stable pulse capacitor voltage over a wide range are problems that must be solved in the design of power supplies for nuclear fusion devices. Utility Model Content

[0003] The purpose of this invention is to provide a high-voltage pulse capacitor charging power supply circuit for linear magnetic confinement fusion devices, especially FRC field inversion fusion devices, to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention adopts the following technical solution, including: The circuit consists of an isolation transformer, a single-phase full-bridge rectifier circuit, a BUCK circuit, a push-pull circuit, a step-up transformer, a voltage multiplier rectifier circuit, a pulse capacitor, and a magnet coil, connected in sequence; the pulse capacitor is C15, and the isolation transformer is T1. The BUCK circuit is connected to the voltage doubler rectifier circuit through a negative feedback circuit; The negative feedback circuit includes a voltage divider circuit; the input of the voltage divider circuit is connected to a voltage doubler rectifier circuit, and the output is sequentially connected to a follower module, a sampling module, a comparator module, and a driver circuit. A front-end BUCK circuit with a push-pull circuit is used to achieve high-frequency AC output, while a rear-end step-up transformer with a voltage doubler rectifier circuit is used to achieve ultra-high DC voltage output. In the event of grid fluctuations or power system oscillations in the front-end, the negative feedback circuit feeds the electrical signal back to the BUCK circuit, thereby achieving a BUCK circuit with closed-loop negative feedback mode, resulting in a high-precision and relatively stable load voltage output.

[0005] When the front-end uses a BUCK circuit, the rear-end adopts a transformer control mode. The BUCK circuit controls the switching ratio to vary between 0 and 100%, and the rear-end can achieve full-range output control from 0 to tens of kV. However, if a conventional high-voltage transformer output plus rectification mode is used, the volume of the transformer core, coil, insulation, etc. will increase exponentially, which is detrimental to the entire nuclear fusion device. Therefore, this invention uses a low-ratio transformer to convert the AC voltage into a few kV voltage, and then outputs tens of kV high voltage through a voltage doubler rectifier circuit.

[0006] Preferably, the single-phase full-bridge rectifier circuit includes a bridge rectifier composed of four diodes D1, D2, D3, and D4, and a capacitor C2 connected in parallel.

[0007] Preferably, the BUCK circuit includes a switching transistor Q1; the base of the switching transistor Q1 is connected to the output terminal of the drive circuit, the collector is connected to the positive terminal of the input voltage, and the emitter is connected to the energy storage inductor L1 and the diode D5 respectively; the diode D5 is connected in parallel with the filter capacitor C3. The BUCK circuit is used to connect to the output terminal of the single-phase full-bridge rectifier circuit, and the PWM output by the drive circuit adjusts the operating state of the BUCK circuit so that the entire circuit stably outputs a 54kV voltage, thereby forming a closed-loop circuit.

[0008] Preferably, the voltage multiplier rectifier circuit includes cascaded voltage multiplier units; the voltage multiplier unit includes a voltage multiplier capacitor and a voltage multiplier diode.

[0009] Preferably, the push-pull circuit includes transistors Q2 and Q3; the emitter of transistor Q3 is connected to one end of the primary winding of the step-up transformer; the emitter of transistor Q2 is connected to the other end of the primary winding of the step-up transformer; and the collectors of transistors Q2 and Q3 are connected in parallel to the negative terminal of the circuit.

[0010] Preferably, the driving circuit includes a driving module; the output terminal of the driving module is connected to a resistor R4 and a diode D16 in parallel; the driving module uses a chip of model UCC23513.

[0011] Compared with the prior art, the embodiments of this utility model have at least the following advantages or beneficial effects: This invention features high control precision, employing a BUCK circuit with a closed-loop negative feedback system to achieve highly accurate and stable charging voltage for the pulse capacitor. It also boasts excellent linearity, utilizing a BUCK circuit combined with a push-pull circuit and a transformer mode to achieve a full-range adjustable voltage output with a wider output voltage range.

[0012] The transformer of this utility model is small in size. It uses a transformer combined with a voltage multiplier rectifier circuit mode, which makes the insulation level of each component in the transformer lower and the insulation treatment simpler. This greatly reduces the volume of the magnetic core, coil, insulation and other components in the transformer. Furthermore, the transformer is installed in the charging power supply box to achieve integration, making the entire power supply device even smaller.

[0013] The power supply device of this utility model is smaller in size. The full-bridge rectifier, BUCK circuit and push-pull circuit in the power supply are integrated on a circuit board. Combined with the circuit board form of voltage doubler rectifier circuit and small-volume transformer, the entire circuit can be installed in a drawer-type box. The overall structure is more flexible, which greatly reduces the size of the device and reduces the cost of the device. Attached Figure Description

[0014] Figure 1 This is an overall structural diagram of the present invention; Figure 2 This is the circuit diagram of this utility model; As shown in the figure: 1-Single-phase full-bridge rectifier circuit, 2-BUCK circuit, 3-Push-pull circuit, 4-Step-up transformer, 5-Voltage multiplier rectifier circuit, 501-Voltage multiplier unit, 6-Negative feedback circuit, 7-Voltage divider circuit, 8-Follower module, 9-Sampling module, 10-Comparison module, 11-Drive circuit, 12-Pulse capacitor, 13-Isolation transformer, 14-Magnetic coil. Detailed Implementation

[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the protection scope of the present utility model.

[0016] Reference Figure 1-2 As shown, this utility model provides a high-voltage pulse capacitor charging power supply circuit: It includes an isolation transformer 13, a single-phase full-bridge rectifier circuit 1, a BUCK circuit 2, a push-pull circuit 3, a step-up transformer 4, a voltage multiplier rectifier circuit 5, a pulse capacitor 12, and a magnet coil 14 connected in sequence. according to Figure 2 As shown, the pulse capacitor 12 is C15, and the isolation transformer 13 is T1; The BUCK circuit 2 is connected to the voltage doubler rectifier circuit 5 through the negative feedback circuit 6; The negative feedback circuit 6 includes a voltage divider circuit 7; the input of the voltage divider circuit is connected to a voltage multiplier rectifier circuit 5, and the output is connected in sequence to a follower module 8, a sampling module 9, a comparison module 10, and a drive circuit 11.

[0017] Specifically, the single-phase full-bridge rectifier circuit 1 includes a bridge rectifier composed of four diodes D1, D2, D3, and D4, and a capacitor C2 connected in parallel.

[0018] Specifically, the BUCK circuit 2 includes a switching transistor Q1; the base of the switching transistor Q1 is connected to the output terminal of the driving circuit 11, the collector is connected to the positive terminal of the input voltage, and the emitter is connected to the energy storage inductor L1 and the diode D5 respectively; the diode D5 is connected in parallel with the filter capacitor C3.

[0019] Specifically, the push-pull circuit 3 includes transistors Q2 and Q3; the emitter of transistor Q3 is connected to one end of the primary winding of the step-up transformer 4; the emitter of transistor Q2 is connected to the other end of the primary winding of the step-up transformer 4; and the collectors of transistors Q2 and Q3 are connected in parallel to the negative terminal of the circuit.

[0020] Specifically, the voltage multiplier rectifier circuit 5 includes cascaded voltage multiplier units 501; the voltage multiplier unit 501 includes a voltage multiplier capacitor and a voltage multiplier diode.

[0021] In a specific scenario, there are 10 voltage multiplier units. The voltage multiplier capacitors include C5, C6, C7, C8, C9, C10, C11, C12, C13, and C14, and the voltage multiplier diodes include D6, D7, D8, D9, D10, D11, D12, D13, D14, and D15. In the first-stage voltage multiplier unit, one end of the voltage multiplier capacitor C5 is connected to one end of the boost transformer T2, and the anode of the voltage multiplier diode D6 is connected to the other end of the boost transformer T2. In the second-stage voltage multiplier unit, one end of the voltage multiplier capacitor C6 is connected to the anode of diode D6, and the other end is connected to the cathode of diode D7. In the third-stage voltage multiplier unit, one end of the voltage multiplier capacitor C7 is connected to the anode of voltage multiplier diode D7, and the other end is connected to the cathode of voltage multiplier diode D8. In the fourth-stage voltage multiplier unit, one end of the voltage multiplier capacitor C8 is connected to the anode of voltage multiplier diode D8, and the other end is connected to the cathode of voltage multiplier diode D7. The cathode of voltage multiplier unit C9 is connected to the anode of voltage multiplier diode D9 and the cathode of voltage multiplier diode D10. The capacitor C10 of the sixth voltage multiplier unit is connected to the anode of voltage multiplier diode D10 and the cathode of voltage multiplier diode D11. The capacitor C11 of the seventh voltage multiplier unit is connected to the anode of voltage multiplier diode D11 and the cathode of voltage multiplier diode D12. The capacitor C12 of the eighth voltage multiplier unit is connected to the anode of voltage multiplier diode D12 and the cathode of voltage multiplier diode D13. The capacitor C13 of the ninth voltage multiplier unit is connected to the anode of voltage multiplier diode D13 and the cathode of voltage multiplier diode D14. The capacitor C14 of the tenth voltage multiplier unit is connected to the anode of voltage multiplier diode D14 and the cathode of voltage multiplier diode D15.

[0022] The voltage doubler rectifier circuit 5 outputs DC 54kV. This 54kV high voltage is then passed through a voltage divider circuit 7, which includes resistors R2 and R3, with resistor R3 having a voltage rating of 600Ω. The resistance value for R2 is 70. The voltage output of the voltage doubler rectifier circuit 5 is proportionally reduced to a safe 6.3V low voltage signal.

[0023] Specifically, the follower module includes a follower chip; the follower chip model is LM358.

[0024] Specifically, the sampling module includes a sampling device; the sampling device is model LV25-NP.

[0025] Specifically, the comparison module includes a feedback chip; the feedback chip is model TL494.

[0026] The 6.3V low voltage signal is voltage followed by the follower chip in the follower module 8. The follower chip outputs a voltage signal, which is linearly converted into a small current signal through the series resistor R7 in the loop.

[0027] The small current signal input sampling module 9 undergoes current isolation conversion through the sampling device LV25-NP Hall sensor. The Hall secondary side outputs a converted current value, which is then converted back into a voltage signal through the parallel bidirectional TVSV1, capacitor C16, and resistor R6. This voltage signal is the feedback voltage that needs to be sampled.

[0028] The feedback voltage input comparison module 10 compares the feedback voltage inside the feedback chip TL494 with a precise reference voltage through pin 1 of the feedback chip, which is the input terminal of the error amplifier. The error signal generated by the comparison changes the duty cycle of the PWM output by TL494.

[0029] The duty cycle input drive circuit 11 includes a drive module; the output terminal of the drive module is connected to a parallel resistor R4 and a diode D16; the drive circuit inputs the PWM signal to the base of the switching transistor Q1 of the BUCK circuit; the BUCK circuit adjusts its operating state to make the entire circuit stably output a 54kV voltage, thereby forming a closed-loop network.

[0030] The above description is merely an example and illustration of the structure of this utility model. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the structure of the utility model or exceed the scope defined in the claims, they should all fall within the protection scope of this utility model.

Claims

1. A high-voltage pulse capacitor charging power supply circuit, characterized in that, The circuit consists of an isolation transformer (13), a single-phase full-bridge rectifier circuit (1), a BUCK circuit (2), a push-pull circuit (3), a step-up transformer (4), a voltage multiplier rectifier circuit (5), a pulse capacitor (12), and a magnet coil (14), which are connected in sequence. The BUCK circuit (2) is connected to the voltage doubler rectifier circuit (5) through the negative feedback circuit (6); The negative feedback circuit (6) includes a voltage divider circuit (7); the input of the voltage divider circuit (7) is connected to a voltage multiplier rectifier circuit (5), and the output is connected in sequence to a follower module (8), a sampling module (9), a comparison module (10), and a driving circuit (11); the output of the driving circuit (11) is connected to the BUCK circuit (2).

2. The high-voltage pulse capacitor charging power supply circuit according to claim 1, characterized in that, The single-phase full-bridge rectifier circuit (1) includes a bridge rectifier composed of diodes D1, D2, D3, and D4.

3. The high-voltage pulse capacitor charging power supply circuit according to claim 1, characterized in that, The BUCK circuit (2) includes a switching transistor Q1; the base of the switching transistor Q1 is connected to the output terminal of the driving circuit (11), the collector is connected to the positive terminal of the input voltage, and the emitter is connected to the energy storage inductor L1 and the diode D5 respectively.

4. The high-voltage pulse capacitor charging power supply circuit according to claim 1, characterized in that, The voltage multiplier rectifier circuit (5) includes multiple cascaded voltage multiplier units (501); each voltage multiplier unit (501) includes a voltage multiplier capacitor and a voltage multiplier diode.

5. The high-voltage pulse capacitor charging power supply circuit according to claim 1, characterized in that, The driving circuit (11) includes a driving module; the output terminal of the driving module is connected to a resistor R4 and a diode D16 in parallel.

6. The high-voltage pulse capacitor charging power supply circuit according to claim 1, characterized in that, The push-pull circuit (3) includes transistors Q2 and Q3; the emitter of transistor Q3 is connected to one end of the primary winding of the step-up transformer (4); the emitter of transistor Q2 is connected to the other end of the primary winding of the step-up transformer (4); the collectors of transistors Q2 and Q3 are connected in parallel and then connected to the input signal.

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