Simulation design method of four-side focusing magnetic field power supply

Abstract

The application relates to the technical field of simulation design, and particularly discloses a simulation design method of a four-side focusing magnetic field power supply, which comprises the following steps: receiving a current instruction and electrical parameters of a quadrupole magnet, wherein the electrical parameters comprise inductance values and resistance values; constructing an electrical parameter deviation table, which is used for storing electrical parameter deviations under different current change scenarios; matching corresponding electrical parameter deviation C from the electrical parameter deviation table according to the change direction and amplitude of the current instruction; and correcting the current instruction according to the electrical parameter deviation C to obtain a target instruction, which is used for driving the simulation operation of the four-side focusing magnetic field power supply. The simulation model dynamically reflects the magnetic hysteresis effect by constructing the electrical parameter deviation table and matching and correcting the current instruction in real time, so that the simulation precision and stability of the four-side focusing magnetic field power supply are significantly improved.

Description

Technical Field

[0001] This invention relates to the field of simulation design technology, and specifically to a simulation design method for a four-sided focusing magnetic field power supply. Background Technology

[0002] A four-sided focusing magnetic field power supply typically refers to a power supply system that provides excitation current to a quadrupole magnet, playing a crucial role in equipment such as particle accelerators. In devices with extremely high precision requirements, such as high-energy synchrotron radiation sources, the four-sided focusing magnetic field power supply needs to provide a long-term stable current to the quadrupole magnet to ensure the precise focusing of the particle beam.

[0003] In the simulation of a four-sided focusing magnetic field power supply, the quadrupole magnet is equivalent to a fixed inductor and resistor, and the dynamic changes in load parameters caused by the hysteresis effect of its magnetic material are ignored. This results in a deviation between the simulated magnetic field response (including the final steady-state value and the dynamic process) and the actual situation, ultimately causing a decrease in beam focusing accuracy. Summary of the Invention

[0004] The purpose of this invention is to provide a simulation design method for a four-sided focusing magnetic field power supply, thereby solving the above-mentioned technical problems.

[0005] The objective of this invention can be achieved through the following technical solutions: A simulation design method for a four-sided focusing magnetic field power source includes the following steps: Receive the current current command and the electrical parameters of the quadrupole magnet, including the inductance and resistance values; Construct an electrical parameter deviation table to store the electrical parameter deviations under different current change scenarios, including current increase, current decrease and current stability. Based on the direction and magnitude of the current current command change, the corresponding electrical parameter deviation C is matched from the electrical parameter deviation table. The direction of change is determined by comparing the difference between the current current command and the current command at the previous moment, and the magnitude is quantified by calculating the absolute value of the difference. The current command is corrected based on the electrical parameter deviation C to obtain the target command, which is used to drive the simulation operation of the four-sided focusing magnetic field power supply.

[0006] As a further aspect of the present invention: constructing an electrical parameter deviation table includes: Set several current command sequences; During the process of applying current command sequence a to the quadrupole magnet, several detection times are set at preset time intervals starting from the time point when current command sequence a is first applied. At the detection time, target data is collected, including the current command value applied to the quadrupole magnet, the actual inductance value and the actual resistance value of the quadrupole magnet; the difference A and difference B between the actual inductance value, the actual resistance value and the preset inductance reference value and resistance reference value are calculated respectively, and the difference A and difference B together constitute the electrical parameter deviation. The electrical parameter deviations are correlated with historical context information, which includes the direction and magnitude of current changes at each past detection moment. All these correlated electrical parameter deviations and historical context information are organized into a queryable electrical parameter deviation table.

[0007] As a further aspect of the present invention: matching the corresponding electrical parameter deviation C from the electrical parameter deviation table includes: Determine the historical context information C1 for the current simulation moment, and record the historical context information in the electrical parameter deviation table that is the same as the historical context information C1 as the target information; Obtain the current change direction Fi and change amplitude Bi corresponding to the detection time i in the target information, and obtain the current change direction F' and current change amplitude B' between the current simulation time and the previous simulation time; If Fi=F' and Bi=B', then the electrical parameter deviation corresponding to the detection time i is recorded as electrical parameter deviation C.

[0008] As a further aspect of the present invention: if there is no detection moment where the current change direction = F' and the change amplitude Bi = B', then the following steps are performed: Obtain the matching degree between the historical context information in the electrical parameter deviation table and the context information C1. If the matching degree is greater than the preset matching degree threshold, mark the corresponding historical context information in the electrical parameter deviation table as candidate information. The difference A and difference B in the electrical parameter deviations corresponding to the candidate information are weighted and summed to obtain new difference A and new difference B. The greater the matching degree, the greater the weight of the candidate information. The new difference A and the new difference B together constitute the electrical parameter deviation C.

[0009] As a further aspect of the present invention: calculating the matching degree includes: For each historical context information in the electrical parameter deviation table, the direction and magnitude of current change at each detection time are sorted according to the time axis to obtain the change sequence of the historical context information, which is denoted as the comparison sequence. The direction and magnitude of current change at each detection moment contained in the historical context information C1 are sorted in chronological order to obtain the change sequence of the historical context information C1, which is denoted as the standard sequence. Among them, the direction and magnitude of the current change at the same detection moment are in a sorted position in the change sequence; The ratio of the target time in the comparison sequence to the total number of detected time is used as the matching degree. If the direction of current change at position j in the comparison sequence is the same as the direction of current change at position j in the standard sequence, and the difference between the magnitude of change at position j in the comparison sequence and the magnitude of change at position j in the standard sequence is less than a preset magnitude difference threshold, then the detection time corresponding to the direction and magnitude of current change at position j in the comparison sequence is recorded as the target time.

[0010] As a further aspect of the present invention: the current command is corrected based on the electrical parameter deviation C to obtain the target current command, including: Analyze the differences A and B corresponding to the electrical parameter deviation C, and denot them as inductance deviation and resistance deviation, respectively; The inductance deviation and resistance deviation are weighted and summed to obtain the current compensation amount. The current compensation amount is used to pre-compensate the effects caused by the actual values ​​of electrical parameters deviating from the reference values ​​in the simulation. The current compensation amount is algebraically summed with the received current current command to generate a preliminary target current command D1. The initial target current command D1 and the target commands generated before it are sorted in chronological order to obtain a time command sequence. The time command sequence is smoothed to convert the initial target current command D1 into a target command D3, which is then used to drive the subsequent simulation.

[0011] As a further aspect of the present invention: smoothing the time instruction sequence includes: Acquire the initial target current instruction D1 and the previous target instruction D2 adjacent to the initial target current instruction in the timing instruction sequence; If the difference between the initial target current command D1 and the target command D2 is greater than the preset difference threshold, then the n target commands adjacent to the initial target current command D1 in the time command sequence are obtained. The n obtained target commands are recorded as correction commands. The weighted average of the correction commands is calculated to obtain the target command D3, where n is the preset number. The earlier the correction command is in the time command sequence, the lower its weight.

[0012] The beneficial effects of this invention compared to the prior art are as follows: (1) By establishing an electrical parameter deviation table before simulation and matching the corresponding deviation in real time according to the direction and amplitude of current change during simulation, this invention enables the simulation model to dynamically correct the deviation of the equivalent inductance and resistance of the quadrupole magnet during operation, thereby maintaining the electrical characteristics calculated in the simulation consistent with the actual hysteresis state. This process enables the simulation results to accurately reflect the real response characteristics of the magnet under different current change scenarios, effectively avoiding the current response lag or distortion caused by fixed model parameters; (2) In the absence of a complete matching record, the present invention uses weighted interpolation based on context similarity to obtain continuous and smooth electrical parameter compensation results under various complex current change modes. This feature ensures that even under current change trajectories that have never appeared before, the simulation can still predict and compensate for parameter drift caused by hysteresis based on historical patterns, realize the continuity and stability of current command correction, and thus improve the simulation's adaptability to dynamic operating conditions and prediction accuracy; (3) By converting electrical parameter deviations into current compensation quantities and smoothing the target current command sequence, this invention can eliminate numerical oscillations caused by command mutations while maintaining simulation stability, ensuring that the generated target current command is physically achievable and changes smoothly. This effect enables the simulation system to maintain high consistency and high reliability during long-term operation, and can more realistically reproduce the steady-state control characteristics of the four-sided focusing magnetic field power supply under dynamic conditions. Attached Figure Description

[0013] The invention will now be further described with reference to the accompanying drawings.

[0014] Figure 1 This is a flowchart illustrating the simulation design method for a four-sided focusing magnetic field power source according to the present invention. Detailed Implementation

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

[0016] Please see Figure 1 As shown, this invention is a simulation design method for a four-sided focusing magnetic field power source, comprising the following steps: Receive the current current command and the electrical parameters of the quadrupole magnet, including the inductance and resistance values; The forward current command refers to the target current setpoint used to control the output of the four-sided focusing magnetic field power supply. It can also be understood as the magnitude of the current that the simulation system or control system expects the power supply to output at the current moment. It is not the actual current, but a "command signal" or "reference value".

[0017] Construct an electrical parameter deviation table to store the electrical parameter deviations under different current change scenarios, including current increase, current decrease and current stability. In a preferred embodiment of the present invention, constructing an electrical parameter deviation table includes: During the experimental preparation phase, several current command sequences need to be designed based on the typical operating characteristics of a quadrupole magnet. These current command sequences are sets of command signals describing the change of current over time, used to simulate different excitation processes. For example, in one current command sequence, the current slowly rises from zero to the rated current and then slowly decreases, reflecting the magnetization changes during the rising and falling phases. Another current command sequence might maintain the current within a stable current range to reflect the characteristics of a hysteresis steady state. The current command sequences should cover various change modes that the equipment may experience during actual operation, including both rapid and slow changes, to ensure the wide applicability of the subsequently constructed deviation table.

[0018] After setting the current command sequence, it is applied one by one to the input terminal of the quadrupole magnet. During the application process, multiple detection times are divided according to a predetermined time interval starting from the start time. The time interval setting should take into account both sampling accuracy and computational load, so that the detection times can fully capture the entire process of hysteresis characteristic changes. At each detection time, target data is collected. The target data consists of three parts: the currently applied current command value, the actual inductance value of the quadrupole magnet measured at the corresponding time, and the actual resistance value.

[0019] After measurement, the actual inductance and resistance are compared with preset inductance and resistance reference values, respectively, and the differences are calculated. The inductance difference is denoted as difference A, and the resistance difference as difference B. Together, they describe the degree of deviation of the electrical characteristics from the ideal state at the current moment. The difference A and difference B at each detection moment are combined to form a set of electrical parameter deviation data. In order for these deviation data to reflect the dynamic changes of the hysteresis effect, they need to be combined with the background information of current changes that cause these deviations. This information is called historical context information. Historical context information records the direction and magnitude of current changes at all moments before the current detection moment. The direction of change is determined by the sign of the difference between the current commands at two adjacent detection moments, and the magnitude of change is represented by the absolute value of the difference. In this way, the electrical parameter deviation is no longer an isolated value, but a dynamic response record containing time correlation.

[0020] Subsequently, the electrical parameter deviations at all detection times and their corresponding historical context information are compiled and organized according to time sequence and current change patterns to form a structured data set, namely the electrical parameter deviation table.

[0021] It is important to note that establishing a mapping relationship between the electrical parameters of the quadrupole magnet and the current change trajectory through experimental data allows the dynamic characteristics of inductance and resistance to be stored in a queryable form. Since the hysteresis effect causes the magnet to exhibit different response curves under different current change paths, this path dependence cannot be reflected by static parameters alone. By introducing the correlation between the current command sequence and the detection time, the hysteresis phenomenon can be reproduced in data form. This allows the simulation system to actively correct the model parameters based on the current command's changing trend during runtime, making the calculation results closer to the actual physical process. Essentially, this process uses historically measured data to give the simulation model a "memory" function. When the current command exhibits a pattern similar to a known trajectory, the simulation can automatically compensate for the corresponding parameter deviations. This allows the simulation model to maintain dynamic tracking of the hysteresis effect during long-term operation, avoiding error accumulation caused by fixed parameters, and making the simulation results more accurate and stable in terms of time evolution and physical response.

[0022] Based on the direction and magnitude of the current current command change, the corresponding electrical parameter deviation C is matched from the electrical parameter deviation table. The direction of change is determined by comparing the difference between the current current command and the current command at the previous moment, and the magnitude is quantified by calculating the absolute value of the difference. In another preferred embodiment of the present invention, matching the corresponding electrical parameter deviation C from the electrical parameter deviation table includes: When performing electrical parameter deviation matching, it is first necessary to clarify the historical context information of the current simulation moment. This information consists of current command change records from several consecutive simulation moments prior to the current moment, including the direction and magnitude of current change at each moment. To obtain this information, the simulation program continuously records the trajectory of current commands on the time axis during operation. When a new current command arrives, it calculates the difference between it and the command at the previous moment and determines whether the current increases, decreases, or remains stable. Simultaneously, it calculates the absolute value of this difference to reflect the magnitude of the change. A simulation moment refers to a discrete time node in the simulation calculation process, that is, the specific point in time when the simulation program performs numerical calculations and updates data on the time axis. During simulation operation, time is divided into many consecutive simulation moments, with a fixed time step interval between adjacent simulation moments. For example, when the simulation program performs numerical calculations at fixed time intervals, the system state is updated every time a time step is reached; this calculation node is a simulation moment.

[0023] Taking a simplified scenario as an example, if the current command at the previous moment was 100 amperes and the current command is 120 amperes, then the direction of change is upward and the magnitude of change corresponds to a difference of 20 amperes. This change, together with the change records of several previous moments, constitutes the historical context information C1 of the current simulation moment.

[0024] Next, we need to find the same historical context information as C1 in the pre-built electrical parameter deviation table. This process is achieved by comparing the current change direction sequence and amplitude sequence contained in each historical record in the deviation table. When the historical context information of any record in the deviation table is completely consistent with C1, it is considered that the context of that record is consistent with the current simulation situation, and the record is marked as the target information.

[0025] After obtaining the target information, the current change direction Fi and amplitude Bi recorded at the corresponding detection time i are read, where i represents any positive integer. Simultaneously, the current change direction F' and amplitude B' within the current calculation cycle are extracted from the current simulation data. If Fi and F' are the same and Bi and B' are consistent, it indicates that the electrical characteristics in the target information perfectly match the current simulation state. In this case, the electrical parameter deviation corresponding to the detection time i can be directly used as the electrical parameter deviation C required for the current simulation. This matching operation can be completed by traversing the deviation table. Once a record meeting the conditions is found, the deviation data can be extracted without additional interpolation or estimation. Through this process, the simulation model can quickly identify the historical records most consistent with the current current change during runtime and use the deviation information to correct the parameters, enabling the electrical characteristics of the simulation model to dynamically follow the changes in the actual hysteresis response.

[0026] It is important to note that by using historical context information to describe the complete path of current change, and by searching for historical trajectories in the deviation table that match the current current change pattern, the path-dependent characteristics of hysteresis can be reproduced at the data level. The magnetization response of a quadrupole magnet is not only related to the current magnitude but also closely related to the direction and speed of current change. The same current value will exhibit different equivalent inductance and resistance under different change paths. By accurately matching historical context information, the simulation model can extract the corresponding deviation values ​​from the actually measured historical data, integrating this nonlinear characteristic dependent on historical paths into real-time simulation calculations. In this way, the correction of electrical parameters is no longer based on simple numerical differences but on physical principles consistent with actual hysteresis behavior. This allows the simulation to possess the same hysteresis characteristics as the real system in dynamic response, fundamentally improving the reliability and stability of the simulation and ensuring a consistent timing relationship between current command and magnetic field response under long-term operation or frequent current regulation.

[0027] In a preferred embodiment, if there is no detection moment where the current change direction = F' and the change amplitude Bi = B', then the following steps are performed: Obtain the matching degree between the historical context information in the electrical parameter deviation table and the context information C1. If the matching degree is greater than the preset matching degree threshold, mark the corresponding historical context information in the electrical parameter deviation table as candidate information. The difference A and difference B in the electrical parameter deviations corresponding to the candidate information are weighted and summed to obtain new difference A and new difference B. The greater the matching degree, the greater the weight of the candidate information. The new difference A and the new difference B together constitute the electrical parameter deviation C.

[0028] It should be noted that the calculation of the matching degree includes: For each historical context information in the electrical parameter deviation table, the direction and magnitude of current change at each detection time are sorted according to the time axis to obtain the change sequence of the historical context information, which is denoted as the comparison sequence. The direction and magnitude of current change at each detection moment contained in the historical context information C1 are sorted in chronological order to obtain the change sequence of the historical context information C1, which is denoted as the standard sequence. Among them, the direction and magnitude of the current change at the same detection moment are in a sorted position in the change sequence; The ratio of the target time in the comparison sequence to the total number of detected time is used as the matching degree. If the direction of current change at position j in the comparison sequence is the same as the direction of current change at position j in the standard sequence, and the difference between the magnitude of change at position j in the comparison sequence and the magnitude of change at position j in the standard sequence is less than a preset magnitude difference threshold, then the detection time corresponding to the direction and magnitude of current change at position j in the comparison sequence is recorded as the target time.

[0029] It's important to note that this approach is based on the inherent characteristics of hysteresis, meaning the magnetization process's dependence on historical paths exhibits a continuous distribution rather than discrete jumps. In reality, there are no strict boundaries between different current-changing trajectories of a magnet; instead, it displays a gradual response under similar conditions. By comparing the time-series similarity of historical context information, reference information can be extracted from similar historical states when completely corresponding data is unavailable, achieving approximate compensation for the current state. This weighted summation method, with matching degree as the weight, is equivalent to interpolation in the historical data space, giving the deviation prediction a smooth transition characteristic, thus avoiding abrupt changes or discontinuities in simulation calculations under boundary conditions. Through this mechanism, the simulation model can maintain a dynamic perception of the hysteresis effect under any current-changing mode, without interrupting the parameter correction process due to a lack of specific scenario samples. In principle, this ensures the continuous consistency and stability of the simulation's nonlinear response to the actual magnet, making the overall simulation results closer to the physical reality.

[0030] The current command is corrected based on the electrical parameter deviation C to obtain the target command, which is used to drive the simulation operation of the four-sided focusing magnetic field power supply.

[0031] In another preferred embodiment of the present invention, the current current command is corrected based on the electrical parameter deviation C to obtain the target current command, including: Analyze the differences A and B corresponding to the electrical parameter deviation C, and denot them as inductance deviation and resistance deviation, respectively; The inductance deviation and resistance deviation are weighted and summed to obtain the current compensation amount. The current compensation amount is used to pre-compensate the effects caused by the actual values ​​of electrical parameters deviating from the reference values ​​in the simulation. The current compensation amount is algebraically summed with the received current current command to generate a preliminary target current command D1. The initial target current command D1 and the target commands generated before it are sorted in chronological order to obtain a time command sequence. The time command sequence is smoothed to convert the initial target current command D1 into a target command D3, which is then used to drive the subsequent simulation.

[0032] It is important to note that after obtaining the electrical parameter deviation, it needs to be converted into an actual correction amount for the current command so that the simulation can reflect the dynamic impact of hysteresis on the electrical characteristics. The electrical parameter deviation C includes changes in both inductance and resistance components. The inductance deviation reflects the hysteresis characteristic of the magnetic flux response, while the resistance deviation reflects the additional changes in energy loss. By weighted summing the two, a numerical relationship can be established between the nonlinear characteristics of the magnetic component and the current output. The resulting current compensation amount is equivalent to a feedforward correction signal, used to preemptively offset the response error caused by the deviation of electrical parameters from the reference value in the simulation. After algebraically summing this current compensation amount with the current command, a preliminary target current command D1 is formed. This ensures that the input signal of the simulation model already has a correction effect before entering the calculation stage, so that the electromagnetic equations inside the model can directly present output changes consistent with the actual hysteresis state during the solution process.

[0033] Subsequently, the time instruction sequence composed of D1 and historical target instructions in chronological order is smoothed to eliminate abrupt changes caused by discrete calculations, making the current change process continuous and stable. The smoothing algorithm makes the current change rate more consistent with physical laws by weighted averaging of adjacent instructions, preventing unreasonable jumps or oscillations in the simulation.

[0034] In a preferred embodiment, smoothing the time instruction sequence includes: Acquire the initial target current instruction D1 and the previous target instruction D2 adjacent to the initial target current instruction in the timing instruction sequence; If the difference between the initial target current command D1 and the target command D2 is greater than the preset difference threshold, then the n target commands adjacent to the initial target current command D1 in the time command sequence are obtained. The n obtained target commands are recorded as correction commands. The weighted average of the correction commands is calculated to obtain the target command D3, where n is the preset number. The earlier the correction command is in the time command sequence, the lower its weight.

[0035] After generating the initial target current command, the current changes in the time series need to be smoothed to ensure that the current changes in the simulation conform to the physical continuity. When the difference between adjacent commands exceeds a preset threshold, it indicates that the current change is too drastic, which may lead to unstable transient fluctuations in the simulation calculation. By extracting multiple historical target commands adjacent to the initial target current command from the time series, constructing a set of correction commands, and performing a weighted average, a transition process can be introduced in the time dimension, making the new target command gradually tend towards a stable change in value. During weighting, commands closer to the current moment are given lower weights to maintain the continuity of the current change trend, while reducing the influence of commands from farther moments, thereby avoiding artificially introduced abrupt changes or overshoot.

[0036] All the above calculations are performed by removing dimensions and taking their numerical values. The formula is a formula obtained from software simulation based on a large amount of collected data, which is the closest to the real situation. The preset parameters and threshold selection in the formula are set by those skilled in the art according to the actual situation.

[0037] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A simulation design method for a four-sided focusing magnetic field power source, characterized in that, Includes the following steps: Receive the current current command and the electrical parameters of the quadrupole magnet, including the inductance and resistance values; Construct an electrical parameter deviation table to store the electrical parameter deviations under different current change scenarios, including current increase, current decrease and current stability. Based on the direction and magnitude of the current current command change, the corresponding electrical parameter deviation C is matched from the electrical parameter deviation table. The direction of change is determined by comparing the difference between the current current command and the current command at the previous moment, and the magnitude is quantified by calculating the absolute value of the difference. The current command is corrected based on the electrical parameter deviation C to obtain the target command, which is used to drive the simulation operation of the four-sided focusing magnetic field power supply. The electrical parameter deviation C matched from the electrical parameter deviation table includes: Determine the historical context information C1 for the current simulation moment, and record the historical context information in the electrical parameter deviation table that is the same as the historical context information C1 as the target information; Obtain the current change direction Fi and change amplitude Bi corresponding to the detection time i in the target information, and obtain the current change direction F' and current change amplitude B' between the current simulation time and the previous simulation time; If Fi=F' and Bi=B', then the electrical parameter deviation corresponding to the detection time i is recorded as electrical parameter deviation C; If there is no detection moment where the current change direction = F' and the change amplitude Bi = B', then perform the following steps: Obtain the matching degree between the historical context information in the electrical parameter deviation table and the context information C1. If the matching degree is greater than the preset matching degree threshold, mark the corresponding historical context information in the electrical parameter deviation table as candidate information. The difference A and difference B in the electrical parameter deviations corresponding to the candidate information are weighted and summed to obtain new difference A and new difference B. The greater the matching degree, the greater the weight of the candidate information. The new difference A and the new difference B together form the electrical parameter deviation C.

2. The simulation design method for a four-sided focusing magnetic field power source according to claim 1, characterized in that, Constructing the electrical parameter deviation table includes: Set several current command sequences; During the process of applying current command sequence a to the quadrupole magnet, several detection times are set at preset time intervals starting from the time point when current command sequence a is first applied. At the detection time, target data is collected, including the current command value applied to the quadrupole magnet, the actual inductance value and the actual resistance value of the quadrupole magnet; the difference A and difference B between the actual inductance value, the actual resistance value and the preset inductance reference value and resistance reference value are calculated respectively, and the difference A and difference B together constitute the electrical parameter deviation. The electrical parameter deviations are correlated with historical context information, which includes the direction and magnitude of current changes at each past detection moment. All these correlated electrical parameter deviations and historical context information are organized into a queryable electrical parameter deviation table.

3. The simulation design method for a four-sided focusing magnetic field power source according to claim 2, characterized in that, The calculation of the matching degree includes: For each historical context information in the electrical parameter deviation table, the direction and magnitude of current change at each detection time are sorted according to the time axis to obtain the change sequence of the historical context information, which is denoted as the comparison sequence. The direction and magnitude of current change at each detection moment contained in the historical context information C1 are sorted in chronological order to obtain the change sequence of the historical context information C1, which is denoted as the standard sequence. Among them, the direction and magnitude of the current change at the same detection moment are in a sorted position in the change sequence; The ratio of the target time in the comparison sequence to the total number of detected time is used as the matching degree. If the direction of current change at position j in the comparison sequence is the same as the direction of current change at position j in the standard sequence, and the difference between the magnitude of change at position j in the comparison sequence and the magnitude of change at position j in the standard sequence is less than a preset magnitude difference threshold, then the detection time corresponding to the direction and magnitude of current change at position j in the comparison sequence is recorded as the target time.

4. The simulation design method for a four-sided focusing magnetic field power source according to claim 3, characterized in that, The current command is corrected based on the electrical parameter deviation C to obtain the target current command, which includes: Analyze the differences A and B corresponding to the electrical parameter deviation C, and denot them as inductance deviation and resistance deviation, respectively; The inductance deviation and resistance deviation are weighted and summed to obtain the current compensation amount. The current compensation amount is used to pre-compensate the effects caused by the actual values ​​of electrical parameters deviating from the reference values ​​in the simulation. The current compensation amount is algebraically summed with the received current current command to generate a preliminary target current command D1. The initial target current command D1 and the target commands generated before it are sorted in chronological order to obtain a time command sequence. The time command sequence is smoothed to convert the initial target current command D1 into a target command D3, which is then used to drive the subsequent simulation.

5. The simulation design method for a four-sided focusing magnetic field power source according to claim 4, characterized in that, Smoothing of time command sequences includes: Acquire the initial target current instruction D1 and the previous target instruction D2 adjacent to the initial target current instruction in the timing instruction sequence; If the difference between the initial target current command D1 and the target command D2 is greater than the preset difference threshold, then the n target commands adjacent to the initial target current command D1 in the time command sequence are obtained. The n obtained target commands are recorded as correction commands. The weighted average of the correction commands is calculated to obtain the target command D3, where n is the preset number. The earlier the correction command is in the time command sequence, the lower its weight.

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