Field antiposition configuration magnetized plasma forming system based on Marx high-voltage pulse generating circuit

Abstract

The invention provides a field antiposition configuration magnetized plasma forming system based on a Marx high-voltage pulse generating circuit, and the system comprises a Marx pulse generating module which is used for generating a high-voltage pulse with high amplitude and narrow pulse width; the voltage stabilization charging module is connected with the Marx pulse generation module and is used for converting the alternating current voltage of the power grid into stable direct current voltage and charging the multi-stage capacitor; the FRC field inversion main body device comprises a restraining coil and a magnetic field detection unit, and the restraining coil is connected with the output end of the Marx pulse generation module and used for receiving the high-voltage pulse and generating a pulsed magnetic field to restrain plasma; the control module is respectively connected with the Marx pulse generation module, the voltage stabilization charging module and the magnetic field detection unit; and the control module dynamically feeds back and adjusts the Marx pulse generation module.

Description

Technical Field

[0001] This invention relates to a plasma formation system, and more specifically to a field-reverse configuration magnetized plasma formation system based on a Marx high-voltage pulse generation circuit. Background Technology

[0002] Controlled nuclear fusion, as a clean, efficient, and sustainable new energy technology, is an important direction for future energy development. Among the many magnetic confinement fusion pathways, field-inverse configuration devices, due to their high β value, can effectively improve fusion power density and significantly reduce dependence on external strong magnetic fields. Especially in the research field of advanced fuel fusion (such as proton-boron-11 and deuterium-helium-3 fusion), FRC devices have demonstrated unique application advantages.

[0003] The core working mechanism of an FRC device lies in constructing a basic magnetic field through external linear coils, which then guides the formation of a reverse magnetic field region within the plasma. This magnetic field is used to confine the ultra-high temperature (up to hundreds of millions of degrees Celsius) plasma, enabling it to meet the conditions for nuclear fusion. This dynamic formation and maintenance process relies on a high-voltage pulsed power supply to drive the confinement coils, generating a pulsed magnetic field with a specific waveform and extremely high amplitude. Therefore, the high-voltage pulse generator is an indispensable core component of the FRC system. However, as controlled nuclear fusion research progresses towards the engineering stage of high-power, long-term stable operation, the high-voltage pulse generation systems used in existing FRC devices have gradually revealed the following serious technical defects that severely restrict their development: First, safety is severely inadequate. Existing high-voltage power supply components mostly employ traditional series discharge circuits, lacking fast and effective overcurrent and short-circuit protection mechanisms. During FRC device operation, plasma states are highly susceptible to transient fluctuations, often leading to sudden load changes or even short circuits at the pulse output terminals. Due to the lack of isolation protection, a failure in any component can easily cause the entire circuit to burn out, potentially affecting core components such as coils and vacuum chambers, resulting in a major safety accident.

[0004] Second, the operational reliability is poor, and pulse parameters are prone to drift. The functional units of the existing device are highly coupled, resulting in severe mutual interference. They are extremely susceptible to fluctuations in grid voltage and changes in ambient temperature, leading to poor stability of the output pulse amplitude and pulse width. In addition, traditional switching elements suffer from huge losses and short service life, forcing experiments to require frequent shutdowns for maintenance, which simply cannot meet the stringent requirements for continuous and stable operation of fusion devices.

[0005] Third, the degree of customization is high but the degree of modularity is low. Most existing high-voltage pulse generators are integrated designs, with charging, discharging, and control units being fixed and bound together, resulting in extremely poor compatibility and scalability. Not only can the number of output stages not be flexibly increased or decreased according to the expansion needs of experiments, but once a part is damaged, the entire unit must be shut down for maintenance, resulting in high maintenance costs and long repair cycles, which seriously hinders the upgrading, transformation, and engineering promotion of FRC devices.

[0006] Marx high-voltage pulse generation circuits, as a mature high-voltage pulse generation technology, can efficiently generate high-amplitude, narrow-pulse-width high-voltage pulses through multi-stage capacitor parallel charging and series discharging, and inherently possess the potential for compact structure and adjustable parameters. However, currently, there is no mature solution in the industry that specifically integrates it deeply into FRC field inversion devices. How to combine the special operating conditions of FRC devices, completely solve the aforementioned pain points of lack of safety, reliability, and modularity, and fully leverage the advantages of Marx circuits and the performance potential of FRC devices has become a pressing technical challenge in this field. Summary of the Invention

[0007] The purpose of this invention is to overcome the technical defects of existing FRC (Field Inversion Configuration) devices, such as insufficient safety, poor reliability, and low modularity. Specifically, this invention aims to solve the problems of easy cascading burnout of existing series components, the inability of traditional open-loop power supplies to adapt to transient plasma changes, and the difficulty of maintenance and upgrades due to integrated design. Therefore, this invention provides a field inversion configuration magnetized plasma formation system and its control method based on a Marx high-voltage pulse generation circuit. The core technical solution of this invention is as follows: To solve the above-mentioned technical problems, the present invention provides a field-reversed configuration magnetized plasma formation system based on a Marx high-voltage pulse generation circuit, comprising: The Marx pulse generation module is used to generate high-amplitude, narrow-pulse-width high-voltage pulses. The Marx pulse generation module includes multi-stage capacitors, all-solid-state switching elements and discharge resistors arranged in series, and adopts a topology structure of multi-stage capacitors charging in parallel and discharging in series. A voltage-regulated charging module, connected to the Marx pulse generator module, is used to convert the AC voltage of the power grid into a stable DC voltage and charge the multi-stage capacitor. The FRC field inversion main device includes a confinement coil and a magnetic field detection unit. The confinement coil is connected to the output terminal of the Marx pulse generation module and is used to receive high-voltage pulses and generate pulsed magnetic fields to confine the plasma. The control module is connected to the Marx pulse generation module, the voltage regulated charging module, and the magnetic field detection unit, respectively. The control module is configured to receive the current magnetic field strength collected in real time by the magnetic field detection unit, calculate the deviation between the current magnetic field strength and the preset target magnetic field strength, as well as the time change rate of the current magnetic field strength, and perform closed-loop control based on the deviation and the time change rate to dynamically adjust the pulse amplitude, pulse width, or frequency of the Marx pulse generation module.

[0008] Furthermore, the control module internally operates a dual closed-loop control strategy based on the deviation and the rate of change over time, and its specific adjustment logic includes: When the rate of decrease of the current magnetic field strength exceeds a set threshold, the Marx pulse generation module is controlled to increase the pulse width to increase the energy injection density. When the current magnetic field strength is lower than the preset target magnetic field strength, the pulse amplitude of the Marx pulse generation module is reduced to decrease the intensity of a single excitation. When the rate of increase of the current magnetic field strength exceeds a set threshold, reverse adjustment is performed to prevent magnetic field overshoot.

[0009] Furthermore, the Marx pulse generation module includes a multi-level cascaded basic unit circuit, and each level of the basic unit circuit includes an energy storage capacitor, an all-solid-state switching element, and a charging isolation diode; During the parallel charging phase, the all-solid-state switching element is in the off state, and the DC voltage output by the voltage regulator charging module charges the energy storage capacitors in each level of the basic unit circuit in parallel through the charging resistor and the charging isolation diode. During the series discharge stage, the control module outputs a synchronous drive signal to drive all the all-solid-state switching elements to conduct simultaneously, so that the energy storage capacitors and all-solid-state switching elements in each level of the basic unit circuit are connected in series, and the superimposed high voltage pulse is output to the constraint coil. The Marx pulse generation module adopts a modular design. According to the pulse amplitude requirements of the FRC field inversion main device, the pulse output amplitude can be directly adjusted by increasing or decreasing the number of stages of the basic unit circuit.

[0010] Furthermore, the voltage-regulated charging module includes a rectifier unit, a filter unit, and a voltage regulator unit connected in sequence; The rectifier unit is used to convert the input AC grid voltage into DC voltage; The filtering unit is used to filter out noise in the DC voltage; The voltage stabilizing unit has a feedback regulation mechanism to eliminate the impact of grid voltage fluctuations on the charging voltage, ensuring that the charging voltage provided to the multi-stage capacitor remains stable.

[0011] Furthermore, the control module uses an FPGA controller as the core control unit; the FPGA controller is configured with an input terminal for receiving voltage sampling signals, current sampling signals, temperature sampling signals and magnetic field sampling signals; the FPGA controller collects the charging voltage, discharging current and system operating temperature of the Marx pulse generator module in real time through the input terminal, and processes them synchronously with the magnetic field strength signal input by the magnetic field detection unit to support the execution of the dual closed-loop control strategy.

[0012] Furthermore, it also includes a protection module; the protection module is communicatively connected to the control module and is used to monitor the operating status of the system in real time; when an overcurrent, overvoltage, short circuit, or surge fault is detected, the protection module triggers a protection action to cut off the relevant circuit and sends a fault signal to the control module to perform alarm and shutdown operations.

[0013] Furthermore, it also includes a heat dissipation module; The heat dissipation module includes heat sinks disposed on the surface of the core components of the Marx pulse generation module and the voltage regulator charging module, as well as a cooling fan for forced air cooling. The heat dissipation module is connected to and controlled by the control module, and is used to maintain the operating temperature of the system within a preset range.

[0014] Furthermore, it also includes a protection module, a heat dissipation module, and an isolation output module; the Marx pulse generation module, the voltage regulated charging module, the protection module, the control module, the heat dissipation module, and the isolation output module are all set as independent functional modules, and the functional modules are detachably connected through standardized interfaces.

[0015] The present invention also provides a control method for a field-inverse configuration magnetized plasma formation system, comprising the following steps: Charging phase: The voltage stabilizing charging module converts the AC voltage of the power grid into a stable DC voltage, and charges the multi-stage capacitors in the Marx pulse generator module in parallel; Discharge and magnetization stage: The control module controls the all-solid-state switching elements to conduct synchronously, causing the Marx pulse generation module to discharge in series, outputting a high-voltage pulse to the constraint coil of the FRC field inversion main device, driving the constraint coil to generate a pulsed magnetic field to constrain the plasma; Real-time feedback adjustment stage: The magnetic field detection unit collects the current magnetic field strength in the FRC field inversion main body device in real time and feeds it back to the control module; The control module calculates the deviation between the current magnetic field strength and the preset target magnetic field strength, as well as the time change rate of the current magnetic field strength, and performs closed-loop control based on the deviation and the time change rate to automatically adjust the amplitude, pulse width or frequency of the next pulse cycle to maintain stable confinement of the plasma.

[0016] The present invention has the following beneficial effects: 1. Precise Closed-Loop Adaptive Control Capability: This application overcomes the bottleneck of traditional pulsed power supplies that rely solely on preset timing for open-loop control. By innovatively introducing a dual closed-loop control strategy based on "magnetic field strength deviation" and "magnetic field change rate," the system can dynamically adjust the pulse amplitude and pulse width with extreme sensitivity and precision according to the transient changes in the plasma confinement state within the FRC device. This adaptive mechanism greatly improves the stability and accuracy of plasma confinement in nuclear fusion experiments.

[0017] 2. Superior system safety and anti-interference capabilities: Abandoning the traditional high-voltage power supply structure that is prone to cascading damage, the system combines a multi-level cascaded architecture with independent protection modules to achieve millisecond-level fault isolation, ensuring that other circuits remain safe and reliable even when a single component is short-circuited. Simultaneously, the independent voltage regulation feedback charging mechanism completely eliminates the impact of grid voltage fluctuations on capacitor charging voltage, guaranteeing absolute stability of pulse output parameters.

[0018] 3. Extremely high modularity and engineering compatibility: The system creatively decomposes the high-voltage pulse generation circuit into multiple independent functional modules, including pulse generation, voltage regulation, control, protection, heat dissipation, and isolated output. These modules are connected detachably using standardized interfaces. This highly modular design not only allows for flexible adjustment of the amplitude by adding or removing stages of the Marx circuit according to experimental needs, but also enables independent disassembly and replacement of single-point faults without requiring a complete system shutdown, significantly reducing maintenance costs and perfectly adapting to the upgrade, modification, and commercialization needs of fusion devices.

[0019] 4. Significantly extended operating life: The adoption of all-solid-state switches completely replaces traditional switching elements, effectively reducing switching losses under high-frequency and high-voltage conditions; and combined with the forced air cooling heat dissipation module that is linked in real time to the controlled module, the temperature of the core components of the system is strictly locked within the safe threshold, thereby fully meeting the stringent operating conditions of high power and long-term continuous operation of controlled nuclear fusion. Attached Figure Description

[0020] Figure 1 This is a block diagram illustrating the overall modular structure of a field-reverse configuration magnetized plasma formation system based on a Marx high-voltage pulse generator circuit, provided in an embodiment of the present invention. Figure 2 The logic block diagram of the dual closed-loop control algorithm based on the FPGA controller provided in the embodiment of the present invention; Figure 3 This is a schematic diagram showing the basic unit circuit of the Marx pulse generation module and the specific circuit connection principle of the FPGA sampling control provided in the embodiments of the present invention. Figure 4 A flowchart illustrating the control method for a field-reverse configuration magnetized plasma formation system provided in an embodiment of the present invention.

[0021] Figure Labels

[0022] 1-Marx pulse generator module; 2- Regulated charging module; 3-FRC field inversion main body device; 31-Constraint coil; 32 - Magnetic field detection unit.

[0023] 4-Control Module Detailed Implementation

[0024] This invention provides a field-reversed configuration magnetized plasma formation system based on a Marx high-voltage pulse generation circuit, comprising: Marx pulse generation module 1 is used to generate high-amplitude, narrow-pulse-width high-voltage pulses. The Marx pulse generation module 1 includes multi-stage capacitors, all-solid-state switching elements and discharge resistors arranged in series, and adopts a topology structure of multi-stage capacitors charging in parallel and discharging in series. The voltage regulator charging module 2 is connected to the Marx pulse generator module 1 and is used to convert the AC voltage of the power grid into a stable DC voltage and charge the multi-stage capacitor. The FRC field inversion main device 3 includes a confinement coil 31 and a magnetic field detection unit 32. The confinement coil 31 is connected to the output terminal of the Marx pulse generation module 1 and is used to receive high voltage pulses and generate pulsed magnetic fields to confine plasma. The control module 4 is connected to the Marx pulse generation module 1, the voltage stabilization charging module 2 and the magnetic field detection unit 32 respectively; The control module 4 is configured to receive the current magnetic field strength collected in real time by the magnetic field detection unit 32, calculate the deviation between the current magnetic field strength and the preset target magnetic field strength, as well as the time change rate of the current magnetic field strength, and perform closed-loop control based on the deviation and the time change rate to dynamically adjust the pulse amplitude, pulse width or frequency of the Marx pulse generation module 1.

[0025] Furthermore, the control module 4 internally operates a dual closed-loop control strategy based on the deviation and the rate of change over time, and its specific adjustment logic includes: When the rate of decrease of the current magnetic field strength exceeds a set threshold, the Marx pulse generation module 1 is controlled to increase the pulse width to increase the energy injection density. When the current magnetic field strength is lower than the preset target magnetic field strength, the pulse amplitude of the Marx pulse generation module 1 is reduced to decrease the intensity of a single excitation. When the rate of increase of the current magnetic field strength exceeds a set threshold, reverse adjustment is performed to prevent magnetic field overshoot.

[0026] Furthermore, the Marx pulse generation module 1 includes a multi-level cascaded basic unit circuit, and each level of the basic unit circuit includes an energy storage capacitor, an all-solid-state switching element, and a charging isolation diode; During the parallel charging phase, the all-solid-state switching element is in the off state, and the DC voltage output by the voltage regulator charging module 2 charges the energy storage capacitors in each level of the basic unit circuit in parallel through the charging resistor and the charging isolation diode. During the series discharge stage, the control module 4 outputs a synchronous drive signal to drive all the all-solid-state switching elements to conduct simultaneously, so that the energy storage capacitors and all-solid-state switching elements in each level of the basic unit circuit are connected in series, and output superimposed high voltage pulses to the constraint coil 31. The Marx pulse generation module 1 adopts a modular design. According to the pulse amplitude requirements of the FRC field inversion main device 3, the pulse output amplitude can be directly adjusted by increasing or decreasing the number of stages of the basic unit circuit.

[0027] Furthermore, the voltage-regulated charging module 2 includes a rectifier unit, a filter unit, and a voltage regulator unit connected in sequence; The rectifier unit is used to convert the input AC grid voltage into DC voltage; The filtering unit is used to filter out noise in the DC voltage; The voltage stabilizing unit has a feedback regulation mechanism to eliminate the impact of grid voltage fluctuations on the charging voltage, ensuring that the charging voltage provided to the multi-stage capacitor remains stable.

[0028] Furthermore, the control module 4 uses an FPGA controller as the core control unit; the FPGA controller is configured with an input terminal for receiving voltage sampling signals, current sampling signals, temperature sampling signals and magnetic field sampling signals; the FPGA controller collects the charging voltage, discharging current and system operating temperature of the Marx pulse generation module 1 in real time through the input terminal, and processes them synchronously with the magnetic field strength signal input by the magnetic field detection unit 32 to support the execution of the dual closed-loop control strategy.

[0029] Furthermore, it also includes a protection module; the protection module is communicatively connected to the control module 4 and is used to monitor the operating status of the system in real time; when an overcurrent, overvoltage, short circuit or surge fault is detected, the protection module triggers a protection action to cut off the relevant circuit and sends a fault signal to the control module 4 to perform alarm and shutdown operations.

[0030] Furthermore, it also includes a heat dissipation module; The heat dissipation module includes heat sinks disposed on the surface of the core components of the Marx pulse generator module 1 and the voltage regulator charging module 2, as well as a cooling fan for forced air cooling. The heat dissipation module is connected to and controlled by the control module 4, and is used to maintain the operating temperature of the system within a preset range.

[0031] Furthermore, it also includes a protection module, a heat dissipation module, and an isolation output module; the Marx pulse generation module 1, the voltage stabilization charging module 2, the protection module, the control module 4, the heat dissipation module, and the isolation output module are all set as independent functional modules, and the functional modules are detachably connected through standardized interfaces.

[0032] The present invention also provides a control method for a field-inverse configuration magnetized plasma formation system, comprising the following steps: Charging stage: The voltage stabilizing charging module 2 converts the AC voltage of the power grid into a stable DC voltage, and charges the multi-stage capacitors in the Marx pulse generation module 1 in parallel; Discharge and magnetization stage: The control module 4 controls the all-solid-state switching element to conduct synchronously, so that the Marx pulse generation module 1 discharges in series and outputs a high-voltage pulse to the constraint coil 31 of the FRC field inversion main body device 3, driving the constraint coil 31 to generate a pulsed magnetic field to constrain the plasma. Real-time feedback adjustment stage: The magnetic field detection unit 32 collects the current magnetic field strength in the FRC field inversion main body device 3 in real time and feeds it back to the control module 4; The control module 4 calculates the deviation between the current magnetic field strength and the preset target magnetic field strength, as well as the time change rate of the current magnetic field strength, and performs closed-loop control based on the deviation and the time change rate to automatically adjust the amplitude, pulse width or frequency of the next pulse cycle to maintain stable confinement of the plasma.

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0034] I. Overall Modular Operating Architecture of the System

[0035] like Figure 1 As shown, the system provided in this embodiment adopts a highly modular and closed-loop interconnection design in terms of physical architecture and signal routing.

[0036] In terms of energy flow, the AC power from the mains is first connected to the regulated charging module 2. The output of the regulated charging module 2 is connected to the power input of the Marx pulse generator module 1 through standardized interfaces such as anti-disconnection heavy-load connectors. The high-amplitude pulses generated by the Marx pulse generator module 1 are impedance matched by the isolation output module and finally fed into the constraint coil 31 of the FRC field inversion main body device 3.

[0037] In the signal control link, the magnetic field detection unit 32 built into the FRC field inversion main device 3 feeds back the acquired high-frequency transient magnetic field signal to the core control module 4 (i.e., the FPGA controller). Simultaneously, the control module 4 also collects voltage, current, and system temperature signals from the regulated charging module 2 and the Marx pulse generator module 1 through corresponding sampling channels. The control module 4 performs comprehensive calculations based on these multi-dimensional signals and sends nanosecond-level synchronous drive signals to the Marx pulse generator module 1 through a standardized interface, thus forming a complete closed loop of energy and information flow.

[0038] II. Topology and Charging / Discharging Mechanism of the Marx Pulse Generation Module

[0039] As the core power unit of this system, the Marx pulse generation module 1 abandons the traditional high-loss switch and adopts a cascaded topology of all-solid-state basic unit circuits. For example... Figure 3 As shown, the following explanation uses a structure containing multiple levels of basic unit circuits as an example: Each basic unit circuit includes an energy storage capacitor (such as...). Figure 3 The components include C1, C2, and C3, IGBTs (such as Q1, Q2, and Q3) used as all-solid-state switching elements, and diodes (such as D2, D4, and D6) used for charging isolation.

[0040] During the parallel charging phase: Control module 4 does not output a synchronous drive signal, and all IGBTs are in the off-state. At this time, the rectification, filtering, and voltage regulation units inside the voltage-regulated charging module 2 work together to output a stable DC high voltage unaffected by grid fluctuations. This DC high voltage charges each energy storage capacitor in parallel through the current-limiting charging resistor (such as R1) and the charging isolation diodes between stages. Thanks to the unidirectional conduction characteristic of the isolation diodes, each stage of capacitor achieves independent equipotential charging, avoiding inter-stage interference.

[0041] During the series discharge phase: When the energy storage capacitor is charged to the target voltage and the system receives a discharge command, the control module 4 simultaneously sends a synchronous drive pulse to the gates of all IGBTs through its output pin. All IGBTs turn on instantaneously, and at this time, the charging isolation diodes of each stage are turned off due to reverse voltage, acting as isolation barriers. The energy storage capacitors of each stage are connected in series with the turned-on IGBTs in sequence, superimposing the voltage and releasing it through the load (i.e., constraint coil 31) in a very short time, thereby generating a high-amplitude, narrow-pulse-width high-voltage pulse with a steep leading edge.

[0042] If the FRC field-reversed main device 3 requires a higher driving voltage due to experimental upgrades, linear capacity expansion can be achieved simply by adding the number of basic unit circuit stages containing "capacitor-IGBT-diode" through a modular standardized interface as needed.

[0043] III. FPGA-based dual closed-loop control algorithm logic

[0044] To completely overcome the shortcomings of existing open-loop pulse power supplies that cannot adapt to transient changes in plasma, the control module 4 (FPGA controller) in this embodiment provides a real-time closed-loop control algorithm specifically designed for the characteristics of FRC devices.

[0045] Combination Figure 2 Algorithm logic block diagram and Figure 4 The flowchart of the control method is shown below, and the specific execution steps of the algorithm are as follows: 1. Control objective: Maintain the magnetic field strength B generated by the confinement coil in the FRC device near the target set value to ensure the stability of plasma confinement.

[0046] 2. Control variables: Input: Magnetic field strength collected in real time by the magnetic field detection unit.

[0047] Output: Pulse amplitude of the Marx pulse generator module

[0048] Feedback quantity: Rate of change of magnetic field strength

[0049] 3. Detailed steps of the FPGA closed-loop control algorithm: Step S1 (Parameter Initialization): The system starts up, sets the target magnetic field strength and allowable error range required to maintain stable plasma confinement, and initializes the reference pulse amplitude Vp and pulse width Tp of Marx pulse generation module 1.

[0050] Step S2 (Real-time Synchronous Calculation): During the discharge excitation stage, the magnetic field detection unit 32 collects the magnetic field strength at the current moment in real time. The logic unit inside control module 4 calculates the magnetic field strength deviation in real time at an extremely high clock frequency. and the rate of change of magnetic field over time in adjacent sampling periods .

[0051] Step S3 (Asymmetric Feedback Intervention): (1) When the rate of decrease of the current magnetic field strength is calculated (negative) When the absolute value of the plasma exceeds the set safety threshold, it indicates that the plasma has a tendency to escape rapidly. At this time, the control module 4 prioritizes adjusting the timing of the synchronous drive signal to extend the conduction time of the IGBT, that is, controlling the Marx pulse generation module 1 to increase the pulse width in order to increase the total energy injection density and forcibly maintain the magnetic field shape.

[0052] (2) When the current magnetic field strength is calculated The magnetic field strength is lower than the preset target strength (i.e. > 0), but when the rate of change is gradual, in order to avoid instability such as plasma tearing caused by sudden full-power pulse, the control module 4 does the opposite and controls to reduce the pulse amplitude of Marx pulse generation module 1 in the next pulse cycle (for example, by reducing the peak charging voltage of the capacitor through voltage regulation signal) to reduce the intensity of a single excitation and achieve flexible and precise magnetization.

[0053] (3) When the magnetic field rises too quickly (positive) When the threshold is exceeded, the pulse width is reduced for reverse adjustment to prevent the magnetic field from overshooting and damaging the vacuum chamber wall.

[0054] The FPGA internally implements a method based on magnetic field strength deviation. and the rate of change of magnetic field The dual closed-loop control strategy dynamically adjusts the pulse amplitude, pulse width, and frequency of the Marx pulse generator module by comparing the deviation between the current magnetic field and the target magnetic field in real time, combined with the magnetic field change trend. Specifically: When the magnetic field descent rate exceeds a set threshold, the FPGA prioritizes increasing the pulse width to increase the energy injection density; When the magnetic field strength is lower than the target value, reduce the pulse amplitude to reduce the intensity of a single excitation. When the magnetic field rises too quickly, it is adjusted in the opposite direction to prevent overshoot.

[0055] This control strategy fully considers the sensitivity of the magnetic field to plasma confinement in the FRC device, and features fast response speed, high adjustment accuracy, and strong adaptability, which is significantly different from the traditional open-loop control method that only relies on preset timing.

[0056] IV. System Support and Security Mechanisms

[0057] In the high-power, strong electromagnetic experimental conditions of controlled nuclear fusion, the system's ultimate safety and thermal balance are crucial. Therefore, this embodiment specifies the following configuration for the system's peripheral support modules: 1. Specific linkage mechanism of the protection module: To prevent damage to the system from abnormally high currents caused by plasma rupture or instantaneous coil insulation failure, the protection module is equipped with a high-speed current transformer and voltage detection circuit in the output main circuit of the Marx pulse generator module 1. During operation, when overcurrent, overvoltage, short circuit, or surge signals exceeding limits are detected in the circuit in real time, the hardware comparison circuit of the protection module will instantly send a highest-priority interrupt trigger signal to the control module 4.

[0058] Within microseconds of receiving the signal, control module 4 immediately blocks the synchronous drive signals of all solid-state switching elements, forcibly cutting off the main discharge circuit. Simultaneously, it activates the parallel bypass discharge branch (such as a thyristor discharge circuit) to safely and quickly channel the residual energy in the multi-stage capacitors into the grounding energy-dissipating resistor for discharge, and simultaneously triggers an audible and visual alarm to shut down the system. This mechanism achieves physical isolation of the fault, effectively preventing the cascading damage accidents commonly seen in high-voltage pulse equipment.

[0059] 2. Specific linkage mechanism of the heat dissipation module: To address the concentrated heat loss generated by all-solid-state switching components during high-frequency, high-voltage switching, the heat dissipation module employs a structure combining passive heat dissipation and active forced cooling. Specifically, high thermal conductivity heat sinks are attached to the surfaces of the core power devices in the Marx pulse generation module 1 and the voltage-regulated charging module 2, and forced air cooling fans are deployed at corresponding locations on the chassis.

[0060] During the discharge excitation phase, control module 4 dynamically adjusts the speed of the cooling fan using PWM (Pulse Width Modulation) technology based on the temperature sampling signal received in real time at its input terminal. This coordinated cooling mechanism can strictly lock the operating temperature of the system's core components within a preset safety threshold range, thereby fully ensuring the system's operational stability and component lifespan under continuous excitation conditions.

[0061] The embodiments described above are merely further illustrations of the present invention and are not intended to limit the present invention in any other way. The present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding modifications and changes based on the present invention, but all such modifications and changes should fall within the protection scope of the present invention.

Claims

1. A field-reversible magnetized plasma formation system based on a Marx high-voltage pulse generator circuit, characterized in that, include: The Marx pulse generation module is used to generate high-amplitude, narrow-pulse-width high-voltage pulses. The Marx pulse generation module includes multi-stage capacitors, all-solid-state switching elements and discharge resistors arranged in series, and adopts a topology structure of multi-stage capacitors charging in parallel and discharging in series. A voltage-regulated charging module, connected to the Marx pulse generator module, is used to convert the AC voltage of the power grid into a stable DC voltage and charge the multi-stage capacitor. The FRC field inversion main device includes a confinement coil and a magnetic field detection unit. The confinement coil is connected to the output terminal of the Marx pulse generation module and is used to receive high-voltage pulses and generate pulsed magnetic fields to confine the plasma. The control module is connected to the Marx pulse generation module, the voltage regulated charging module, and the magnetic field detection unit, respectively. The control module is configured to receive the current magnetic field strength collected in real time by the magnetic field detection unit, calculate the deviation between the current magnetic field strength and the preset target magnetic field strength, as well as the time change rate of the current magnetic field strength, and perform closed-loop control based on the deviation and the time change rate to dynamically adjust the pulse amplitude, pulse width, or frequency of the Marx pulse generation module.

2. The system according to claim 1, characterized in that, The control module internally operates a dual closed-loop control strategy based on the deviation and the rate of change over time. Its specific adjustment logic includes: When the rate of decrease of the current magnetic field strength exceeds a set threshold, the Marx pulse generation module is controlled to increase the pulse width to increase the energy injection density. When the current magnetic field strength is lower than the preset target magnetic field strength, the pulse amplitude of the Marx pulse generation module is reduced to decrease the intensity of a single excitation. When the rate of increase of the current magnetic field strength exceeds a set threshold, reverse adjustment is performed to prevent magnetic field overshoot.

3. The system according to claim 1, characterized in that, The Marx pulse generation module includes a multi-level cascaded basic unit circuit, and each level of the basic unit circuit includes an energy storage capacitor, an all-solid-state switching element, and a charging isolation diode. During the parallel charging phase, the all-solid-state switching element is in the off state, and the DC voltage output by the voltage regulator charging module charges the energy storage capacitors in each level of the basic unit circuit in parallel through the charging resistor and the charging isolation diode. During the series discharge stage, the control module outputs a synchronous drive signal to drive all the all-solid-state switching elements to conduct simultaneously, so that the energy storage capacitors and all-solid-state switching elements in each level of the basic unit circuit are connected in series, and the superimposed high voltage pulse is output to the constraint coil. The Marx pulse generation module adopts a modular design. According to the pulse amplitude requirements of the FRC field inversion main device, the pulse output amplitude can be directly adjusted by increasing or decreasing the number of stages of the basic unit circuit.

4. The system according to claim 1, characterized in that, The voltage-regulated charging module includes a rectifier unit, a filter unit, and a voltage regulator unit connected in sequence. The rectifier unit is used to convert the input AC grid voltage into DC voltage; The filtering unit is used to filter out noise in the DC voltage; The voltage stabilizing unit has a feedback regulation mechanism to eliminate the impact of grid voltage fluctuations on the charging voltage, ensuring that the charging voltage provided to the multi-stage capacitor remains stable.

5. The system according to claim 1, characterized in that, The control module uses an FPGA controller as the core control unit. The FPGA controller is equipped with an input terminal for receiving voltage sampling signals, current sampling signals, temperature sampling signals, and magnetic field sampling signals. The FPGA controller collects the charging voltage, discharging current, and operating temperature of the Marx pulse generator module in real time through the input terminal and processes them synchronously with the magnetic field strength signal input by the magnetic field detection unit.

6. The system according to claim 1, characterized in that, It also includes a protection module; The protection module is communicatively connected to the control module and is used to monitor the operating status of the system in real time. When an overcurrent, overvoltage, short circuit, or surge fault is detected, the protection module triggers a protection action to disconnect the relevant circuit and sends a fault signal to the control module to perform alarm and shutdown operations.

7. The system according to claim 1, characterized in that, It also includes a heat dissipation module; The heat dissipation module includes heat sinks disposed on the surface of the core components of the Marx pulse generation module and the voltage regulator charging module, as well as a cooling fan for forced air cooling. The heat dissipation module is connected to and controlled by the control module, and is used to maintain the operating temperature of the system within a preset range.

8. The system according to claim 1, characterized in that, It also includes a protection module, a heat dissipation module, and an isolation output module; the Marx pulse generation module, voltage regulation charging module, protection module, control module, heat dissipation module, and isolation output module are all set as independent functional modules, and the functional modules are detachably connected through standardized interfaces.

9. A control method for a field-reverse configuration magnetized plasma formation system according to any one of claims 1-8, characterized in that, Includes the following steps: Charging phase: The voltage stabilizing charging module converts the AC voltage of the power grid into a stable DC voltage, and charges the multi-stage capacitors in the Marx pulse generator module in parallel; Discharge and magnetization stage: The control module controls the all-solid-state switching elements to conduct synchronously, causing the Marx pulse generation module to discharge in series, outputting a high-voltage pulse to the constraint coil of the FRC field inversion main device, driving the constraint coil to generate a pulsed magnetic field to constrain the plasma; Real-time feedback adjustment stage: The magnetic field detection unit collects the current magnetic field strength in the FRC field inversion main body device in real time and feeds it back to the control module; The control module calculates the deviation between the current magnetic field strength and the preset target magnetic field strength, as well as the time change rate of the current magnetic field strength, and performs closed-loop control based on the deviation and the time change rate to automatically adjust the amplitude, pulse width or frequency of the next pulse cycle to maintain stable confinement of the plasma.

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