Accelerator magnet power supply based on superconducting magnetic energy storage device and working method thereof

Abstract

The invention belongs to the technical field of superconducting magnetic energy storage, and discloses an accelerator magnet power supply based on a superconducting magnetic energy storage device and a working method thereof. The accelerator magnet power supply comprises an AC-DC rectifier, a bus capacitor, a magnet side H bridge, a superconducting magnetic energy storage side H bridge and a superconducting magnetic energy storage device. The bus capacitor is connected with the superconducting magnetic energy storage device through the superconducting magnetic energy storage side H bridge; the superconducting magnetic energy storage side H bridge is used for realizing energy conversion between the superconducting magnetic energy storage device and the bus capacitor by controlling the bridge arm switch tube; the superconducting magnetic energy storage device is used for storing reactive energy used for interacting with the magnet load in the bus capacitor. According to the technical scheme disclosed by the invention, the superconducting magnetic energy storage device and the corresponding superconducting magnetic energy storage side H bridge are arranged, so that the energy conversion efficiency of a magnet power supply can be improved, and meanwhile, the problem of impact of pulse current on a power grid can be solved.

Description

Technical Field

[0001] This invention belongs to the field of superconducting magnetic energy storage technology, and specifically relates to an accelerator magnet power supply based on a superconducting magnetic energy storage device and its working method. Background Technology

[0002] In accelerator systems, the accelerator magnet power supply provides pulsed current to the magnets to generate the magnetic field required for particle acceleration. However, rapid changes in current occur during the charging and discharging of the magnets. These fluctuations can cause grid voltage instability, affecting the normal operation of other equipment on the same grid and reducing the power quality, reliability, and stability of the power supply. Explained, due to the inductive properties of the magnets, they rapidly absorb a large amount of energy from the grid during charging, causing a momentary increase in grid current; conversely, during discharging, they rapidly release the stored energy back into the grid, causing drastic fluctuations in grid voltage and current.

[0003] Given the above, the existing traditional solutions mainly fall into the following three categories: 1. A switching pulse-width modulation rectifier is used as the magnet power supply. Constant power charging and discharging is achieved through its internal energy storage capacitor, enabling bidirectional control of energy flow from the capacitor to the grid. During magnet charging and discharging, the energy storage capacitor acts as a buffer, reducing the impact of power pulses on the grid. However, this method has limitations: the capacitor's lifespan is limited, and high-frequency charging and discharging easily leads to aging; furthermore, the capacitor's self-discharge rate is high, and the storage time is short, causing the stored energy to gradually dissipate over time, thus reducing the energy conversion efficiency of the magnet power supply.

[0004] 2. This method combines high-voltage and low-voltage power supplies, using a switching device to achieve rapid switching between the two voltage levels, thereby reducing the impact of rapid power fluctuations on the power grid. However, this method still has drawbacks: instantaneous voltage and current fluctuations may occur during switching, affecting the stability of the power system; furthermore, the additional switching device increases the complexity of system control.

[0005] 3. Static var compensators (SVCs) are used to rapidly adjust the reactive power of the system during the charging and discharging of the magnetic load, thus suppressing grid voltage fluctuations. However, this method has a drawback: the millisecond-level response time of SVCs is typically insufficient to meet the power compensation requirements of microsecond-level pulses in fast-pulse magnetic power supplies. Summary of the Invention

[0006] The purpose of this invention is to provide an accelerator magnet power supply based on a superconducting magnetic energy storage device and its operating method, in order to solve one or more of the aforementioned technical problems. The technical solution disclosed in this invention includes a superconducting magnetic energy storage device (SMES) and a corresponding superconducting magnetic energy storage side H-bridge, which can improve the energy conversion efficiency of the magnet power supply and simultaneously solve the problem of pulse current impact on the power grid.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides an accelerator magnet power supply based on a superconducting magnetic energy storage device, comprising: an AC-DC rectifier, a bus capacitor and a magnet-side H-bridge connected in series, and further comprising: a superconducting magnetic energy storage-side H-bridge and a superconducting magnetic energy storage device. The bus capacitor is connected to the superconducting magnetic energy storage device via the superconducting magnetic energy storage side H-bridge; wherein, the superconducting magnetic energy storage side H-bridge is used to realize the energy conversion between the superconducting magnetic energy storage device and the bus capacitor by controlling the bridge arm switching tube; the superconducting magnetic energy storage device is used to store the reactive energy in the bus capacitor for interaction with the magnetic load.

[0008] A further improvement of the technical solution of the present invention is that the superconducting magnetic energy storage side H-bridge is provided with a left bridge arm and a right bridge arm, each bridge arm is provided with two switching tubes, and a connection point for connecting the bus capacitor is provided between the two switching tubes; the superconducting magnetic energy storage device is connected in parallel at both ends of the left bridge arm and the right bridge arm. The four switching transistors are turned on and off by receiving on / off control signals, and the two switching transistors on each bridge arm cannot be turned on at the same time; the on / off control signals are set according to the set working mode.

[0009] A further improvement to the technical solution of the present invention lies in the following specific steps for setting the on / off control signal according to the set working mode: In the operating mode where the magnet load obtains energy from the grid side for excitation, the grid, through the isolation transformer, AC-DC rectifier, bus capacitor, magnet-side H-bridge, and magnet load, forms a magnet excitation circuit. At this time, the on / off control signal is that all four switching transistors are turned off. In the operating mode of magnet load demagnetization and superconducting magnetic energy storage device excitation, the bus capacitor, magnet-side H-bridge, magnet load, superconducting magnetic energy storage side H-bridge, and superconducting magnetic energy storage device constitute a magnet discharge circuit. At this time, the on / off control signal controls the conduction sequence of four switching transistors to excite the superconducting magnetic energy storage device. During the excitation process of the superconducting magnetic energy storage device, the switching transistor conduction combination is determined according to the voltage polarity of the bus capacitor and the desired current direction of the superconducting magnetic energy storage device. In the demagnetized and magnet-load-excited operating mode of the superconducting magnetic energy storage device, the bus capacitor, magnet-side H-bridge, magnet load, superconducting magnetic energy storage-side H-bridge, and superconducting magnetic energy storage device constitute a magnet charging circuit. At this time, the on / off control signal controls the conduction sequence of the four switching transistors to excite the magnet load. During the magnet load excitation process, the switching transistor conduction combination is determined according to the voltage polarity of the bus capacitor and the desired current direction of the superconducting magnetic energy storage device. In the working mode where the energy stored by the magnetic load is returned to the grid through the bus capacitor, the grid forms a magnetic demagnetization circuit through the isolation transformer, AC-DC rectifier, bus capacitor, magnetic H-bridge, and magnetic load. At this time, the on / off control signal is that all four switching transistors are turned off.

[0010] A further improvement of the technical solution of the present invention is that, in the superconducting magnetic energy storage H-bridge, the left bridge arm is provided with a switching tube from top to bottom. S 1. S 4. The right bridge arm is equipped with switch tubes from top to bottom. S 3. S 2; where the switching transistor is located. S 1. S A first connection point is set between 4, and the switch tube is used. S 2. S A second connection point is provided between 3, and the first and second connection points are respectively connected to the two ends of the bus capacitor.

[0011] A further improvement to the technical solution of this invention lies in the following steps for determining the switching transistor conduction combination during the excitation process of the superconducting magnetic energy storage device, based on the voltage polarity of the bus capacitor and the desired current direction of the superconducting magnetic energy storage device: If the voltage across the bus capacitor is positive at the top and negative at the bottom, and the desired superconducting magnetic energy storage device experiences a current flowing from top to bottom, then the switching transistor will be turned on. S 1. S 2. A closed loop is formed; if the voltage across the bus capacitor is negative at the top and positive at the bottom, and the desired superconducting magnetic energy storage device experiences a current flowing from top to bottom, then the switching transistor is turned on. S 3. S 4. Form a closed loop; If the voltage across the bus capacitor is positive at the top and negative at the bottom, and the desired superconducting magnetic energy storage device experiences an upward current flow, then the switching transistor will be turned on. S 3. S 4. A closed loop is formed; if the voltage across the bus capacitor is negative at the top and positive at the bottom, and the desired superconducting magnetic energy storage device experiences an upward current flow, then the switching transistor is turned on. S 1. S 2. Form a closed loop.

[0012] A further improvement to the technical solution of this invention lies in the following steps for determining the switching transistor conduction combination during the magnet load excitation process, based on the voltage polarity of the bus capacitor and the desired current direction of the superconducting magnetic energy storage device: If the voltage across the bus capacitor is positive at the top and negative at the bottom, and the desired superconducting magnetic energy storage device experiences a current flowing from top to bottom, then the switching transistor will be turned on. S 1. S 2. A closed loop is formed; if the voltage across the bus capacitor is negative at the top and positive at the bottom, and the desired superconducting magnetic energy storage device experiences a current flowing from top to bottom, then the switching transistor is turned on. S 3. S 4. Form a closed loop; If the voltage across the bus capacitor is positive at the top and negative at the bottom, and the desired superconducting magnetic energy storage device experiences an upward current flow, then the switching transistor will be turned on. S 3. S 4. A closed loop is formed; if the voltage across the bus capacitor is negative at the top and positive at the bottom, and the desired superconducting magnetic energy storage device experiences an upward current flow, then the switching transistor is turned on. S 1. S 2. Form a closed loop.

[0013] A further improvement of the technical solution of the present invention is that the switching transistor in the superconducting magnetic energy storage side H-bridge is composed of an IGBT and an anti-parallel diode.

[0014] A further improvement to the technical solution of the present invention is that it further includes: The controller is used to output the on / off control signal.

[0015] In a second aspect, the present invention provides an accelerator magnet power supply system, which employs an accelerator magnet power supply based on a superconducting magnetic energy storage device as described in any one of the first aspects of the present invention; wherein, one end of the accelerator magnet power supply based on the superconducting magnetic energy storage device is used to connect to a magnet load, and the other end is used to connect to the power grid via an isolation transformer.

[0016] In a third aspect, the present invention provides a method for operating an accelerator magnet power supply based on a superconducting magnetic energy storage device as described in the first aspect of the present invention, wherein the superconducting magnetic energy storage device and the bus capacitor are used as a whole to compensate for or absorb reactive power during the operation of the magnet load.

[0017] Compared with the prior art, the present invention has the following beneficial effects: Existing conventional solutions address the impact on the power grid during accelerator magnet load operation by using energy storage capacitors in the magnet power supply, switching between high-voltage and low-voltage power supplies, and static var compensators (SVCs). Given the remaining problems with these conventional solutions, this invention discloses an accelerator magnet power supply based on a superconducting magnetic energy storage device. This device combines the existing magnet power supply's energy storage capacitor with a SMES (Spiritual Var Compensator) device, reducing system reactive power losses while mitigating the impact of the magnet load on the power grid as a whole. In this invention, the superconducting magnetic energy storage device and the corresponding superconducting magnetic energy storage-side H-bridge improve the energy conversion efficiency of the magnet power supply and simultaneously address the impact of pulsed currents on the power grid. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the overall architecture of an accelerator magnet power supply system provided in an embodiment of the present invention; wherein, the accelerator magnet power supply based on a superconducting magnetic energy storage device disclosed in an embodiment of the present invention is used. Figure 2 This is a schematic diagram of the connection between the bus capacitor and the superconducting magnetic energy storage device and the structure of the H-bridge on the side of the superconducting magnetic energy storage device in the accelerator magnet power supply based on the superconducting magnetic energy storage device disclosed in the embodiments of the present invention. The explanations of the reference numerals in the figure are as follows: 1. Power grid; 2. Isolation transformer; 3. AC-DC rectifier; 4. Bus capacitor; 5. Magnet-side H-bridge; 6. Magnet load; 7. Superconducting magnetic energy storage-side H-bridge; 8. Superconducting magnetic energy storage device; 9. Controller. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention; obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0021] Based on the technical solutions disclosed in the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or devices.

[0022] Please see Figure 1 An accelerator magnet power supply system provided in this embodiment of the invention includes: a power grid 1, an isolation transformer 2, a magnet load 6, and an accelerator magnet power supply based on a superconducting magnetic energy storage device disclosed below in this embodiment of the invention; wherein, The accelerator magnet power supply based on the superconducting magnetic energy storage device is connected to the power grid 1 at one end via the isolation transformer 2, and to the magnet load 6 at the other end; further explained, the power grid 1 is used to provide the energy source for the whole system; the isolation transformer 2 is used to change the voltage level of the power grid 1 in the power transmission and distribution process; The accelerator magnet power supply based on the superconducting magnetic energy storage device includes: an AC-DC rectifier 3, a bus capacitor 4, a magnet-side H-bridge 5, a superconducting magnetic energy storage-side H-bridge 7, and a superconducting magnetic energy storage device 8; wherein, the AC-DC rectifier 3, the bus capacitor 4, and the magnet-side H-bridge 5 are connected in series, the AC-DC rectifier 3 is used to connect to the isolation transformer 2 outside the accelerator magnet power supply, and the magnet-side H-bridge 5 is used to connect to the magnet load 6 outside the accelerator magnet power supply; the superconducting magnetic energy storage device 8 is connected to the connecting wire between the AC-DC rectifier 3 and the bus capacitor 4 via the superconducting magnetic energy storage-side H-bridge 7; further explained, the AC-DC rectifier 3 is used for Three-phase AC power is rectified into DC power, commonly using two methods: uncontrolled diode rectification and switching pulse width modulation rectification. Bus capacitor 4 is used to store reactive power during the charging and discharging process of magnet load 6 in the short term and to provide a stable voltage for the subsequent H-bridge. Magnet-side H-bridge 5 is used to excite / demagnetize magnet load 6 by controlling its bridge arm switches. Magnet load 6 is used to generate the magnetic field required for accelerator operation after excitation. In addition, superconducting magnetic energy storage-side H-bridge 7 is used to realize energy conversion between superconducting magnetic energy storage device 8 and bus capacitor 4 by controlling its bridge arm switches. Superconducting magnetic energy storage device 8 is used to store reactive power in bus capacitor 4 for interaction with magnet load 6 in the long term.

[0023] In the technical solution provided by this invention, a superconducting magnetic energy storage H-bridge 7 and a superconducting magnetic energy storage device 8 are further added to the conventional accelerator power supply composed of an AC-DC rectifier 3, a bus capacitor 4, and a magnet-side H-bridge 5. This reduces the energy dissipation of the bus capacitor 4 in the conventional power supply and solves the impact of pulse current on the power grid 1 through the synergistic effect of the bus capacitor 4 and the superconducting magnetic energy storage device 8. This invention aims to transfer the energy stored in the energy storage capacitor of the magnet power supply through the superconducting magnetic energy storage device, leveraging the advantages of the low self-discharge rate and long energy storage time of the SMES (Signaled Electromagnetic Storage System), reducing the energy dissipation of the energy storage capacitor in the traditional magnet power supply, thereby improving the energy conversion efficiency of the magnet power supply. Furthermore, the SMES and the energy storage capacitor, as a whole, are used to compensate for / absorb the reactive power required during the operation of the magnet load, thereby solving the problem of pulse current impact on the power grid.

[0024] Explanation of the principle of the technical solution of the embodiments of the present invention: When the system is connected to an AC power source, the AC-DC rectifier 3 converts the AC power into DC power. This process is usually achieved through a diode bridge rectifier circuit or a thyristor rectifier circuit to ensure that the output DC power has a certain degree of stability and controllability.

[0025] Bus capacitor 4 plays the role of filtering and energy storage in DC circuit. It can absorb the ripple component in the pulsating DC output of rectifier, making the DC bus voltage smoother and more stable. At the same time, when the system power demand changes, bus capacitor 4 can release or store a certain amount of energy to maintain the stability of the bus voltage.

[0026] The H-bridge 7 on the superconducting magnetic energy storage side consists of four switching devices. By controlling the on / off state of these switching devices, the charging and discharging control of the superconducting magnetic energy storage device 8 can be achieved. During charging, the H-bridge converts the DC bus voltage into a current suitable for the superconducting coil, enabling the superconducting magnetic energy storage device 8 to store energy. During discharging, the H-bridge converts the energy released by the superconducting magnetic energy storage device 8 back to the DC bus voltage and feeds it back to the system.

[0027] The superconducting magnetic energy storage device 8 utilizes the zero-resistance characteristic of superconducting materials. In the superconducting state, current can circulate losslessly within the superconducting coil, achieving efficient energy storage. When the system requires additional power support, the superconducting magnetic energy storage device 8 can quickly release the stored energy through the superconducting magnetic energy storage side H-bridge 7 to supplement the system's power demand. When the system has excess power, the superconducting magnetic energy storage device 8 can absorb the excess energy and store it for later use.

[0028] In this embodiment of the invention, the collaborative working mechanism between the conventional accelerator power supply and the superconducting magnetic energy storage device is clarified through the above connection relationship and working principle explanation, which can improve the power regulation capability and stability of the system.

[0029] Please see Figure 2 In this embodiment of the invention, the association between the bus capacitor and the SMES, as well as the control scheme of the H-bridge on the superconducting magnetic energy storage side, are further described in detail. For example... Figure 2 As shown, C This refers to the capacitance value of the bus capacitor; the superconducting magnetic energy storage H-bridge includes a left bridge arm and a right bridge arm, each with two switching transistors. Each switching transistor can specifically consist of an insulated-gate bipolar transistor (IGBT) and an anti-parallel diode (in the example illustrative technical solution, the anode of the anti-parallel diode is connected to the emitter of the IGBT, and the cathode is connected to the collector of the IGBT); such as Figure 2 As shown, the left bridge arm contains the switching transistor. S 1. S 4. The right bridge arm includes the switch tube. S 2. S 3; Four switching transistors are controlled to turn on and off via on / off control signals transmitted by controller 9, ensuring that no two switching transistors on each bridge arm can be turned on simultaneously to prevent short circuits in the bridge arm. S 1. S 4. Switching transistors do not conduct simultaneously S 2. S 3. Not conducting simultaneously.

[0030] In this embodiment of the invention, the overall operation of the system can be divided into the following modes. The specific process of controlling the four switching transistors to turn on and off through the on / off control signal of the controller is as follows: In the operating mode where the magnet load obtains energy for excitation from the grid side, the conventional accelerator power supply operates normally according to traditional methods, and the switching transistors... S 1. S 2. S 3. S 4 are not conducting at this time. Figure 1 The magnetic excitation circuit consists of the power grid 1, isolation transformer 2, AC-DC rectifier 3, bus capacitor 4, magnet-side H-bridge 5, and magnet load 6.

[0031] Operating modes of magnet load demagnetization and SMES excitation. Figure 1 The bus capacitor 4, magnet-side H-bridge 5, magnet load 6, superconducting magnetic energy storage-side H-bridge 7, and superconducting magnetic energy storage device 8 constitute a magnet discharge circuit, which is controlled by a switching transistor. S 1. S 2. S 3. S The conduction sequence of 4 is SMES excitation. Further illustratively, since the magnetic field of the magnet load 6 is bidirectional, the excitation current of SMES is also bidirectional; if... Figure 2 If the current flows from top to bottom through the SMES bus, and the voltage across the bus capacitor 4 is positive at the top and negative at the bottom when the magnet is demagnetized, then the switching transistor will be turned on. S1. S 2. A closed loop is formed; if the voltage across the bus capacitor 4 is negative on the top and positive on the bottom when the magnet is demagnetized, then the switching transistor is turned on. S 3. S 4. Form a closed loop. If... Figure 2 If current flows from bottom to top through the SMES, the switch conduction method is the opposite of that described above.

[0032] In the SMES demagnetization and magnet load excitation operating modes Figure 1 The bus capacitor 4, magnet-side H-bridge 5, magnet load 6, superconducting magnetic energy storage-side H-bridge 7, and superconducting magnetic energy storage device 8 constitute the magnet charging circuit, which is connected by a switching transistor. S 1- S The conduction sequence of 4 is that the magnet load 6 is energized. This stage differs from the second mode mentioned above only in the direction of energy flow; the conduction method of the switching transistor will not be described again.

[0033] In the operating mode where the energy stored by the magnetic load is returned to the grid via the bus capacitor, the conventional accelerator power supply operates normally according to traditional methods, switching... S 1- S All 4 are not conducting. Figure 1 The magnet demagnetizing circuit consists of the central power grid 1, isolation transformer 2, AC-DC rectifier 3, bus capacitor 4, magnet-side H-bridge 5, and magnet load 6.

[0034] In the technical solution provided by this invention, the energy stored in the energy storage capacitor in the magnet power supply is transferred by the SMES (Signal-Enhanced Electromagnetic Suppressor), leveraging the advantages of SMES's low self-discharge rate and long energy storage time to reduce energy dissipation of the energy storage capacitor in traditional magnet power supplies, thereby improving the energy conversion efficiency of the magnet power supply. Furthermore, the SMES and bus capacitor, as a whole, are used to compensate for / absorb the reactive power required during the operation of the magnet load, thus solving the problem of pulse current impact on the power grid.

[0035] In summary, this invention comprises a superconducting magnetic energy storage device and a superconducting magnetic energy storage-side H-bridge. The superconducting magnetic energy storage device has low or even zero resistance characteristics. When storing reactive quantities used in the bus capacitor for interaction with the magnetic load, it does not suffer energy loss due to resistance like traditional capacitors. The superconducting magnetic energy storage-side H-bridge realizes energy conversion between the superconducting magnetic energy storage device and the bus capacitor by controlling the bridge arm switching transistors. This energy conversion method avoids the aging problem caused by high-frequency charging and discharging of traditional capacitors, because the charging and discharging process of the superconducting magnetic energy storage device does not produce physical losses similar to capacitor aging. The system comprised of the superconducting magnetic energy storage device and the superconducting magnetic energy storage-side H-bridge of this invention can precisely control the energy conversion between the superconducting magnetic energy storage device and the bus capacitor during the charging and discharging process of the magnet load. Specifically, when the magnet load changes, the superconducting magnetic energy storage device can respond quickly by adjusting the energy flow through the superconducting magnetic energy storage-side H-bridge, eliminating the need for voltage level changes via switching switches as in traditional solutions. Furthermore, the four switches of the superconducting magnetic energy storage-side H-bridge are turned on and off respectively by receiving on / off control signals, and the two switches on each bridge arm cannot be turned on simultaneously. This precise control method allows for stable energy adjustment according to the set operating mode, avoiding instantaneous voltage and current fluctuations caused by switch switching. Superconducting magnetic energy storage devices possess rapid response characteristics, enabling energy storage and release within microseconds. The H-bridge on the superconducting magnetic energy storage side, through rapid control of the bridge arm switches, can precisely regulate the energy conversion between the superconducting magnetic energy storage device and the bus capacitor. This allows for a rapid response and adjustment of the system's reactive power when fast pulses are generated by the charging and discharging of the magnetic load, meeting the power compensation requirements of the microsecond-level pulses in the fast-pulse magnetic power supply. In summary, the technical solution of this invention effectively solves the problem of power compensation for fast-pulse magnetic power supplies, promptly suppressing grid voltage fluctuations and ensuring the stable operation of the magnetic power supply under fast-pulse operating conditions.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. An accelerator magnet power supply based on a superconducting magnetic energy storage device, comprising: The AC-DC rectifier (3), bus capacitor (4) and magnet-side H-bridge (5) connected in series are characterized in that they further include: superconducting magnetic energy storage side H-bridge (7) and superconducting magnetic energy storage device (8). The bus capacitor (4) is connected to the superconducting magnetic energy storage device (8) via the superconducting magnetic energy storage side H-bridge (7); wherein, the superconducting magnetic energy storage side H-bridge (7) is used to realize the energy conversion between the superconducting magnetic energy storage device (8) and the bus capacitor (4) by controlling the bridge arm switching tube; the superconducting magnetic energy storage device (8) is used to store the non-functional quantity in the bus capacitor (4) for interaction with the magnetic load.

2. The accelerator magnet power supply based on a superconducting magnetic energy storage device according to claim 1, characterized in that, The superconducting magnetic energy storage H-bridge (7) is provided with a left bridge arm and a right bridge arm. Each bridge arm is provided with two switching tubes, and a connection point for connecting the bus capacitor (4) is provided between the two switching tubes. The superconducting magnetic energy storage device (8) is provided in parallel at both ends of the left bridge arm and the right bridge arm. The four switching transistors are turned on and off by receiving on / off control signals, and the two switching transistors on each bridge arm cannot be turned on at the same time; the on / off control signals are set according to the set working mode.

3. An accelerator magnet power supply based on a superconducting magnetic energy storage device according to claim 2, characterized in that, The specific steps for setting the on / off control signal according to the set working mode are as follows: In the working mode where the magnet load obtains energy from the grid side for excitation, the grid forms a magnet excitation circuit through the isolation transformer, AC-DC rectifier (3), bus capacitor (4), magnet-side H-bridge (5), and magnet load. At this time, the on / off control signal is that all four switching transistors are turned off. In the working mode of magnet load demagnetization and superconducting magnetic energy storage device excitation, the bus capacitor (4), magnet-side H-bridge (5), magnet load, superconducting magnetic energy storage side H-bridge (7) and superconducting magnetic energy storage device (8) constitute a magnet discharge circuit. At this time, the on / off control signal controls the conduction sequence of the four switching tubes to excite the superconducting magnetic energy storage device (8). During the excitation process of the superconducting magnetic energy storage device (8), the switching tube conduction combination is determined according to the voltage polarity of the bus capacitor (4) and the desired current direction of the superconducting magnetic energy storage device (8). In the working mode of demagnetizing and magnet load excitation of the superconducting magnetic energy storage device, the bus capacitor (4), magnet-side H-bridge (5), magnet load, superconducting magnetic energy storage-side H-bridge (7) and superconducting magnetic energy storage device (8) constitute the magnet charging circuit. At this time, the on / off control signal controls the conduction sequence of the four switching tubes to excite the magnet load. During the magnet load excitation process, the switching tube conduction combination is determined according to the voltage polarity of the bus capacitor (4) and the desired current direction of the superconducting magnetic energy storage device (8). In the working mode where the energy stored by the magnet load is returned to the grid through the bus capacitor, the grid forms a magnet demagnetization circuit through the isolation transformer, AC-DC rectifier (3), bus capacitor (4), magnet-side H-bridge (5), and magnet load. At this time, the on / off control signal is that all four switching transistors are turned off.

4. An accelerator magnet power supply based on a superconducting magnetic energy storage device according to claim 3, characterized in that, In the superconducting magnetic energy storage H-bridge (7), the left bridge arm is equipped with a switching tube from top to bottom. S 1. S 4. The right bridge arm is equipped with switch tubes from top to bottom. S 3. S 2; Among them, the switching transistor S 1. S A first connection point is set between 4, and the switch tube is used. S 2. S A second connection point is provided between 3, and the first connection point and the second connection point are respectively connected to the two ends of the bus capacitor (4).

5. An accelerator magnet power supply based on a superconducting magnetic energy storage device according to claim 4, characterized in that, During the excitation process of the superconducting magnetic energy storage device (8), the specific steps for determining the switching transistor conduction combination based on the voltage polarity of the bus capacitor (4) and the desired current direction of the superconducting magnetic energy storage device (8) are as follows: If the voltage of the bus capacitor (4) is positive at the top and negative at the bottom, and the desired superconducting magnetic energy storage device (8) has a current flowing from top to bottom, then the switching transistor is turned on. S 1. S 2. A closed loop is formed; if the voltage of the bus capacitor (4) is negative at the top and positive at the bottom, and the desired superconducting magnetic energy storage device (8) has a current flowing from top to bottom, then the switching transistor is turned on. S 3. S 4. Form a closed loop; If the voltage of the bus capacitor (4) is positive at the top and negative at the bottom, and the desired superconducting magnetic energy storage device (8) has a current flowing from bottom to top, then the switching transistor is turned on. S 3. S 4. A closed loop is formed; if the voltage of the bus capacitor (4) is negative at the top and positive at the bottom, and the desired superconducting magnetic energy storage device (8) has a current flowing from bottom to top, then the switching transistor is turned on. S 1. S 2. Form a closed loop.

6. An accelerator magnet power supply based on a superconducting magnetic energy storage device according to claim 4, characterized in that, During the magnet load excitation process, the specific steps for determining the switching transistor conduction combination based on the voltage polarity of the bus capacitor (4) and the desired current direction of the superconducting magnetic energy storage device (8) are as follows: If the voltage of the bus capacitor (4) is positive at the top and negative at the bottom, and the desired superconducting magnetic energy storage device (8) has a current flowing from top to bottom, then the switching transistor is turned on. S 1. S 2. A closed loop is formed; if the voltage of the bus capacitor (4) is negative at the top and positive at the bottom, and the desired superconducting magnetic energy storage device (8) has a current flowing from top to bottom, then the switching transistor is turned on. S 3. S 4. Form a closed loop; If the voltage of the bus capacitor (4) is positive at the top and negative at the bottom, and the desired superconducting magnetic energy storage device (8) has a current flowing from bottom to top, then the switching transistor is turned on. S 3. S 4. A closed loop is formed; if the voltage of the bus capacitor (4) is negative at the top and positive at the bottom, and the desired superconducting magnetic energy storage device (8) has a current flowing from bottom to top, then the switching transistor is turned on. S 1. S 2. Form a closed loop.

7. An accelerator magnet power supply based on a superconducting magnetic energy storage device according to claim 1, characterized in that, The switching transistors in the superconducting magnetic energy storage side H-bridge (7) are composed of IGBTs and anti-parallel diodes.

8. An accelerator magnet power supply based on a superconducting magnetic energy storage device according to claim 2, characterized in that, Also includes: The controller (9) is used to output the on / off control signal.

9. An accelerator magnet power supply system, characterized in that, An accelerator magnet power supply based on a superconducting magnetic energy storage device, as described in any one of claims 1 to 8, is used; wherein one end of the accelerator magnet power supply based on the superconducting magnetic energy storage device is used to connect to a magnet load, and the other end is used to connect to the power grid via an isolation transformer.

10. A method for operating an accelerator magnet power supply based on a superconducting magnetic energy storage device as described in claim 1, characterized in that, The superconducting magnetic energy storage device (8) and the bus capacitor (4) are used as a whole to compensate for or absorb reactive power during the operation of the magnetic load.

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