Parallel quasi-proportional-resonant control method and system for scanning power supply

Abstract

This invention provides a parallel quasi-proportional resonant control method and system for a scanning power supply, relating to the field of accelerator technology. The method includes: acquiring an error signal between a reference current signal and the actual output current signal of the scanning power supply; inputting the error signal to a parallel quasi-proportional resonant controller, the parallel quasi-proportional resonant controller comprising a proportional element and at least two parallel quasi-proportional resonant elements; the resonant center frequencies of the at least two parallel quasi-proportional resonant elements corresponding to the fundamental frequency and at least one odd harmonic frequency of the triangular wave represented by the reference current signal, respectively; the parallel quasi-proportional resonant controller outputting a control signal based on the error signal; and generating a pulse width modulation signal based on the control signal to control the switching transistors of the scanning power supply, so that the actual output current signal tracks the reference current signal. This invention achieves zero steady-state error tracking without relying on a large integral gain, thus allowing for the design of a larger proportional gain and improved outer-loop dynamic response speed.

Description

Technical Field

[0001] This invention relates to the field of accelerator technology, and in particular to a parallel quasi-proportional resonant control method and system for scanning power supplies. Background Technology

[0002] In physics experiments such as heavy ion beam irradiation, the magnet scanning method is often used to expand the beam to cover a large area of ​​the sample. This method achieves precise deflection of the beam by controlling the current in the scanning magnet. The scanning power supply is the core component, and its performance directly determines the quality of the beam scan. To obtain good linearity, scanning range, and uniformity, the scanning power supply typically needs to output a bipolar triangular wave current.

[0003] Currently, the industry-standard technical solution for this type of scanning power supply is to use an H-bridge topology combined with a traditional proportional-integral (PI) control algorithm. However, from a control theory perspective, PI control has inherent technical limitations when dealing with the requirements of high-precision triangular wave current tracking, specifically in the following aspects: Steady-state tracking error exists. According to internal model theory, the controller must include a mathematical model of the controlled signal to achieve error-free tracking. The integral element model of the PI controller (transfer function 1 / s) can only achieve error-free tracking of step (DC) signals. However, a bipolar triangular wave can be decomposed into a series of cosine signals of different frequencies under Fourier series, and its model does not match that of the PI controller. Therefore, when using PI control to track triangular wave current, a steady-state error is theoretically inevitable, making it difficult to meet the high precision requirements of the scanning power supply.

[0004] Insufficient anti-interference capability. The frequency domain characteristics of a PI controller are equivalent to a low-pass filter, which lacks frequency-selective suppression capability for high-frequency disturbances. In actual operation, this may lead to the amplification of high-frequency disturbances at non-target frequencies, thereby affecting the stability of the output current and failing to meet the stringent anti-interference requirements of the power supply in complex electromagnetic environments.

[0005] The dynamic response speed is relatively slow. In PI control, a large integral gain is usually required to compensate for tracking errors to some extent. However, an excessively large integral gain limits the range of proportional gain to prevent system oscillations or instability. This constraint between gain parameters ultimately results in a slow dynamic response speed of the controller's outer loop, making it unable to quickly respond to the dynamic adjustment requirements of the current during beam scanning. Summary of the Invention

[0006] This invention provides a parallel quasi-proportional resonant control method and system for scanning power supplies, which solves the defects of low tracking accuracy, weak anti-interference ability and slow dynamic response speed in the prior art when using PI control algorithm to control scanning power supply to track bipolar triangular waves, and achieves a larger proportional gain and improves the dynamic response speed of the outer loop.

[0007] This invention provides a parallel quasi-proportional resonant control method for a scanning power supply, comprising: Obtain the error signal between the reference current signal and the actual output current signal of the scanning power supply; The error signal is input to a parallel quasi-proportional resonant controller, which includes a proportional element and at least two parallel quasi-proportional resonant elements; wherein the resonant center frequencies of the at least two parallel quasi-proportional resonant elements correspond to the fundamental frequency and at least one odd harmonic frequency of the triangular wave characterized by the reference current signal, respectively. The parallel quasi-proportional resonant controller outputs a control signal based on the error signal; A pulse width modulation signal is generated based on the control signal to control the switching transistor of the scanning power supply, thereby causing the actual output current signal to track the reference current signal.

[0008] According to the parallel quasi-proportional resonance control method for scanning power supply provided by the present invention, the resonant center frequency is determined by Fourier decomposition of the triangular wave characterized by the reference current signal.

[0009] According to the parallel quasi-proportional resonant control method for scanning power supply provided by the present invention, the at least one odd harmonic frequency includes at least one of the 3rd harmonic frequency, the 5th harmonic frequency, and the 7th harmonic frequency.

[0010] According to the parallel quasi-proportional resonant control method for scanning power supply provided by the present invention, the parallel quasi-proportional resonant controller is implemented by the difference equation obtained by discretizing the continuous domain transfer function.

[0011] According to the parallel quasi-proportional resonant control method for scanning power supply provided by the present invention, the discretization is accomplished using a bilinear transformation method.

[0012] According to the parallel quasi-proportional resonant control method for scanning power supply provided by the present invention, the continuous domain transfer function is: , in, This is the proportional gain coefficient. Let be the resonant gain coefficient of the i-th resonant element. Let be the cutoff frequency of the i-th resonant element. Let be the resonant center frequency of the i-th resonant element, and N be the number of odd harmonics selected. It is a complex frequency variable.

[0013] According to the parallel quasi-proportional resonant control method for a scanning power supply provided by the present invention, the scanning power supply adopts an H-bridge topology.

[0014] The present invention also provides a parallel quasi-proportional resonant control system for scanning power supply, comprising the following modules: The error acquisition module is used to acquire the error signal between the reference current signal and the actual output current signal of the scanning power supply. A controller module, connected to the error acquisition module, is used to implement a parallel quasi-proportional resonant controller. The parallel quasi-proportional resonant controller includes a proportional element and at least two parallel quasi-proportional resonant elements. The resonant center frequencies of the at least two parallel quasi-proportional resonant elements correspond to the fundamental frequency and at least one odd harmonic frequency of the triangular wave represented by the reference current signal, respectively. The parallel quasi-proportional resonant controller outputs a control signal based on the error signal. A PWM generation module, connected to the controller module, is used to generate a pulse width modulation signal according to the control signal to control the switching transistor of the scanning power supply, so that the actual output current signal tracks the reference current signal.

[0015] According to the parallel quasi-proportional resonant control system for scanning power supply provided by the present invention, the controller module is a digital signal processor or a field-programmable gate array.

[0016] According to the parallel quasi-proportional resonant control system for scanning power supply provided by the present invention, the controller module is configured to realize the function of the parallel quasi-proportional resonant controller by executing a difference equation obtained by discretizing a continuous domain transfer function.

[0017] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the parallel quasi-proportional resonant control method for scanning power supply as described above.

[0018] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the parallel quasi-proportional resonant control method for scanning power supply as described above.

[0019] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the parallel quasi-proportional resonant control method for scanning power supply as described above.

[0020] This invention provides a parallel quasi-proportional resonant control method and system for scanning power supplies. By performing spectral analysis on the target triangular wave and employing multiple quasi-proportional resonant elements to precisely compensate for the gain of the fundamental wave and key odd harmonic components of the triangular wave, it fundamentally solves the steady-state tracking error problem caused by model mismatch in traditional PI control. This significantly improves the linearity and accuracy of the output current waveform, achieving high-precision current tracking. Through frequency selection, the system gain is precisely concentrated on the effective harmonic frequencies of the triangular wave, while the gain for signals outside these specific frequencies, especially high-frequency noise and disturbances, is extremely low. This characteristic effectively avoids the amplification of high-frequency disturbances, significantly improving the system's anti-interference performance and the stability of the output current, thus enhancing the system's anti-interference capability. Structurally, this invention ensures zero steady-state error tracking of the target signal, eliminating the need for large integral gain to compensate for steady-state errors as in PI control. This allows the proportional gain in the controller to be set larger while maintaining system stability, resulting in a wider control bandwidth and faster dynamic response speed. It can respond more quickly to dynamic changes in the reference current, improving the system's dynamic response speed. Attached Figure Description

[0021] 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.

[0022] Figure 1 This is a schematic flowchart of the parallel quasi-proportional resonance control method for scanning power supply provided by the present invention.

[0023] Figure 2 This is a schematic diagram illustrating the principle of the parallel quasi-proportional resonant control method for scanning power supply in H-bridge topology provided by the present invention.

[0024] Figure 3 This is a schematic diagram of the parallel quasi-proportional resonant control system for scanning power supply provided by the present invention.

[0025] Figure 4 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0027] The present invention will now be described in detail with reference to the accompanying drawings. The specific operation methods in the method embodiments can also be applied to the device embodiments or system embodiments. In the description of the present invention, unless otherwise stated, "at least one" includes one or more. "Multiple" refers to two or more. For example, at least one of A, B, and C includes: A existing alone, B existing alone, A and B existing simultaneously, A and C existing simultaneously, B and C existing simultaneously, and A, B, and C existing simultaneously. In the present invention, " / " means "or". For example, A / B can mean A or B. "And / or" in this document is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone.

[0028] The present invention will now be described in detail with reference to specific embodiments.

[0029] In some specific embodiments of the present invention, such as Figure 1 As shown, this solution provides a parallel quasi-proportional resonant control method for a scanning power supply, including: Step S100: Obtain the error signal between the reference current signal and the actual output current signal of the scanning power supply; Step S200: Input the error signal to a parallel quasi-proportional resonant controller. The parallel quasi-proportional resonant controller includes a proportional element and at least two parallel quasi-proportional resonant elements. The resonant center frequencies of the at least two parallel quasi-proportional resonant elements correspond to the fundamental frequency of the triangular wave represented by the reference current signal and at least one odd harmonic frequency, respectively. Step S300: The parallel quasi-proportional resonant controller outputs a control signal based on the error signal; Step S400: Generate a pulse width modulation signal according to the control signal to control the switching transistor of the scanning power supply, so that the actual output current signal tracks the reference current signal.

[0030] It should be noted that existing proportional-integral (PI) controller technologies for tracking bipolar triangular waves in scanning power supplies can only achieve zero steady-state error tracking for step signals, not for bipolar triangular waves, thus failing to meet the high-precision current output requirements of scanning power supplies. The frequency domain characteristics of the PI controller are equivalent to a low-pass filter, lacking selective suppression of high-frequency disturbances at non-target frequencies. This characteristic can lead to amplification of high-frequency disturbances, affecting the stability of the current output and making it difficult to meet the stringent anti-interference requirements of scanning power supplies. Furthermore, the PI controller relies on a large integral gain to compensate for tracking errors to some extent; however, a large integral gain limits the design space of the proportional gain. Excessive proportional gain can easily lead to system instability. This contradiction results in a slow dynamic response speed in the outer loop of the controller, making it unable to quickly respond to the dynamic adjustment requirements of the current output during beam scanning.

[0031] To address the aforementioned shortcomings, this invention proposes a Parallel Quasi-Proportional Resonant Control (PQPR) algorithm to replace the traditional PI control algorithm. According to internal model control theory, a bipolar triangular wave is essentially a combination of different cosine signals, and the transfer function of the cosine signal is: ,in, Represents the Laplace transform operator. t For time, For complex frequency variables, This is the angular frequency of the cosine signal. Therefore, the controller model must include this frequency. Theoretically, proportional resonant controllers are more suitable for tracking triangular waves than PI controllers.

[0032] Furthermore, PQPR has theoretical advantages in anti-interference capabilities. The essence of proportional resonant control is to amplify signals at a specific frequency; for high-frequency disturbances at non-resonant frequencies, the low-gain characteristic of PQPR can prevent the disturbances from being amplified. Compared to the frequency domain characteristics of the equivalent low-pass filter in PI control, PQPR's frequency selectivity is far superior to PI control for tracking triangular waves. Finally, PQPR can achieve zero steady-state error without relying on a large integral gain, thus allowing for the design of larger proportional gains and improved outer-loop dynamic response speed.

[0033] In summary, this invention achieves zero steady-state error tracking of the fundamental and harmonic waves by matching the spectral structure of a triangular wave and setting the resonant center frequency of the quasi-proportional resonant circuit to correspond to the fundamental and odd harmonic frequencies of the triangular wave, significantly improving current output accuracy. Furthermore, the parallel quasi-proportional resonant controller exhibits frequency selectivity, with high gain for resonant frequency signals and low gain for high-frequency disturbances at non-resonant frequencies, effectively suppressing high-frequency disturbances and improving system stability. Moreover, this invention achieves zero steady-state error without relying on large integral gain, allowing for the design of larger proportional gains, thereby accelerating the system's dynamic response speed. It is suitable for tracking control of various periodic non-sinusoidal waveforms, such as triangular waves, sawtooth waves, and square waves, and possesses good scalability and versatility.

[0034] The following is in conjunction with the appendix Figure 2 The above steps will be explained in detail.

[0035] Please see the appendix Figure 2 , Figure 2 A system block diagram of a specific embodiment of the present invention is shown. The system controls a scanning power supply employing an H-bridge topology, which supplies power to a resistive-inductive load. At the core of the entire control system is a controller module, which can be a digital signal processor (DSP) or a field-programmable gate array (FPGA). This controller module executes the parallel quasi-proportional resonant (PQPR) control method proposed in this invention.

[0036] In this embodiment, an H-bridge algorithm is verified with the following operating parameters: input DC voltage of 1670V, load is a resistive-inductive load with a resistance of 0.03Ω and an inductance of 2.6mH. The target output reference current signal is a bipolar triangular wave with a frequency of 200Hz and a peak value of 545A. Its variation within one complete cycle is as follows: 0ms ~ 1.25ms: The current rises linearly from 0A to 545A; 1.25ms ~ 2.5ms: The current decreases linearly from 545A to 0A; 2.5ms ~ 3.75ms: The current decreases linearly from 0A to -545A; 3.75ms ~ 5ms: The current rises linearly from -545A to 0A.

[0037] The specific implementation steps of the PQPR control method of the present invention are as follows: Step S201: Perform Fourier decomposition on the target reference triangular waveform; Before applying the control algorithm, it is necessary to first determine the resonant center frequency of each resonant element in the PQPR controller.

[0038] In some possible embodiments of the invention, the resonant center frequency is determined by Fourier decomposition of the triangular wave characterized by the reference current signal. The at least one odd harmonic frequency includes at least one of the 3rd, 5th, and 7th harmonic frequencies.

[0039] Specifically, before applying the algorithm, the reference triangular waveform needs to be Fourier decomposed to obtain its fundamental frequency, third harmonic frequency, fifth harmonic frequency, seventh harmonic frequency, ..., which will serve as the resonant center frequency of the subsequent PQPR controller.

[0040] For example, by performing Fourier decomposition on the aforementioned 200Hz bipolar triangular wave, its spectrum can be obtained as consisting of a fundamental wave and a series of odd harmonics. The fundamental frequency is 200Hz, the third harmonic frequency is 600Hz, the fifth harmonic frequency is 1000Hz, the seventh harmonic frequency is 1400Hz, and so on. In this invention, the frequencies of the fundamental wave and several lower harmonics are selected as the resonant center frequencies ω of the multiple quasi-proportional resonant elements connected in parallel in the subsequent PQPR controller. i .

[0041] Step S202: Discretize the PQPR transfer function; In some possible embodiments of the present invention, the parallel quasi-proportional resonant controller is implemented by using the difference equation obtained by discretizing the continuous domain transfer function.

[0042] In some possible embodiments of the present invention, the continuous domain transfer function of the PQPR controller used in the present invention It can be represented as: (1), in, For complex frequency variables, This is the proportional gain coefficient; Let be the resonant gain coefficient of the i-th resonant element; The cutoff frequency of the i-th resonant element affects the tracking response speed; is the resonant center frequency of the i-th resonant element; N is the number of odd harmonics selected, where N represents the number of odd harmonics selected for proportional resonant amplification after Fourier decomposition of the reference triangular waveform.

[0043] In some possible embodiments of the present invention, the discretization is performed using a bilinear transformation method.

[0044] Specifically, to implement this algorithm in a digital controller, the continuous-domain transfer function needs to be converted into a difference equation using a discretization method. In this embodiment, the bilinear transform (Tustin transform) method is employed, letting... ,in, For the Z-transform operator, This represents the system sampling period. Through the above bilinear transformation, the continuous s-domain model is mapped to the discrete z-domain, thus obtaining the difference equation between the controller output control quantity and the error signal, which has the following specific form: (2); in, For the current moment The error signal, For the current moment The control quantity output by the controller, For the first At the current moment, the resonant element... The output quantity, its recursive calculation formula is: (3), in, This represents the error between the first two time points. , Let these represent the state variables of the i-th resonant element at the previous time step and the two time steps before that, respectively. For the corresponding number The discretization coefficients of each resonant element are expressed as follows: (4); (5); (6).

[0045] The S203 and PQPR control algorithms implement current closed-loop control.

[0046] The error signal is obtained by subtracting the reference current from the real-time output current collected by the sensor. The error signal is then substituted into the discretization formula obtained in step S202 to calculate the control signal. The control signal is then modulated by a comparator and a triangular wave to output a PWM wave to control the switching transistor to output current.

[0047] Specifically, within each control cycle, the system uses a current sensor (such as...) Figure 2 (As shown) The actual output current from the H-bridge output to the load is collected to obtain the actual output current signal value. The difference between this signal value and the reference current signal value at the same time is used to obtain the error signal e(k).

[0048] Then, the error signal e(k), along with the historical error values ​​and state variables, are substituted into the difference equation in step S202 to calculate the control signal x(k) required for the current cycle.

[0049] Finally, the control signal x(k) is sent to the PWM generation module. The PWM generation module compares the control signal with a triangular carrier wave (modulation wave) to generate a corresponding pulse width modulation (PWM) signal. This PWM signal drives the four switches (such as IGBTs) of the H-bridge to turn on and off, thereby precisely controlling the output current and enabling it to track the reference triangular wave current signal with high accuracy.

[0050] Through the above method, the present invention can effectively overcome the defects of traditional PI control and significantly improve the output current quality of the scanning power supply.

[0051] The parallel quasi-proportional resonant control system for scanning power supply provided by the present invention will be described below. The parallel quasi-proportional resonant control system for scanning power supply described below can be referred to in correspondence with the parallel quasi-proportional resonant control method for scanning power supply described above.

[0052] In some specific embodiments of the present invention, such as Figure 3 As shown, this solution provides a parallel quasi-proportional resonant control system for scanning power supplies, including: Error acquisition module 10 is used to acquire the error signal between the reference current signal and the actual output current signal of the scanning power supply; The controller module 20, connected to the error acquisition module, is used to implement a parallel quasi-proportional resonant controller. The parallel quasi-proportional resonant controller includes a proportional element and at least two parallel quasi-proportional resonant elements. The resonant center frequencies of the at least two parallel quasi-proportional resonant elements correspond to the fundamental frequency and at least one odd harmonic frequency of the triangular wave represented by the reference current signal, respectively. The parallel quasi-proportional resonant controller outputs a control signal according to the error signal. The PWM generation module 30, connected to the controller module, is used to generate a pulse width modulation signal according to the control signal to control the switching transistor of the scanning power supply, so that the actual output current signal tracks the reference current signal.

[0053] The controller module may be a digital signal processor or a field-programmable gate array.

[0054] Possibly, the controller module is configured to implement the function of the parallel quasi-proportional resonant controller by executing a difference equation obtained by discretizing a continuous domain transfer function.

[0055] Figure 4 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 4As shown, the electronic device may include a processor 410, a communications interface 420, a memory 430, and a communication bus 440, wherein the processor 410, communications interface 420, and memory 430 communicate with each other via the communication bus 440. The processor 410 can call logic instructions in the memory 430 to execute a parallel quasi-proportional resonant control method for a scanning power supply. This method includes: acquiring an error signal between a reference current signal and the actual output current signal of the scanning power supply; inputting the error signal to a parallel quasi-proportional resonant controller, the parallel quasi-proportional resonant controller including a proportional element and at least two parallel quasi-proportional resonant elements; wherein the resonant center frequencies of the at least two parallel quasi-proportional resonant elements correspond to the fundamental frequency and at least one odd harmonic frequency of the triangular wave represented by the reference current signal, respectively; the parallel quasi-proportional resonant controller outputting a control signal based on the error signal; and generating a pulse width modulation signal based on the control signal to control the switching transistor of the scanning power supply, thereby causing the actual output current signal to track the reference current signal.

[0056] Furthermore, the logical instructions in the aforementioned memory 430 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0057] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the parallel quasi-proportional resonant control method for scanning power supply provided by the above methods. The method includes: acquiring an error signal between a reference current signal and the actual output current signal of the scanning power supply; inputting the error signal to a parallel quasi-proportional resonant controller, the parallel quasi-proportional resonant controller including a proportional element and at least two parallel quasi-proportional resonant elements; wherein the resonant center frequencies of the at least two parallel quasi-proportional resonant elements correspond to the fundamental frequency and at least one odd harmonic frequency of the triangular wave represented by the reference current signal, respectively; the parallel quasi-proportional resonant controller outputs a control signal according to the error signal; and generates a pulse width modulation signal according to the control signal to control the switching transistor of the scanning power supply, thereby causing the actual output current signal to track the reference current signal.

[0058] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, performs the parallel quasi-proportional resonant control method for scanning power supply provided by the methods described above. The method includes: acquiring an error signal between a reference current signal and an actual output current signal of the scanning power supply; inputting the error signal to a parallel quasi-proportional resonant controller, the parallel quasi-proportional resonant controller including a proportional element and at least two parallel quasi-proportional resonant elements; wherein the resonant center frequencies of the at least two parallel quasi-proportional resonant elements correspond respectively to the fundamental frequency of the triangular wave characterized by the reference current signal and at least one odd harmonic frequency; the parallel quasi-proportional resonant controller outputting a control signal according to the error signal; and generating a pulse width modulation signal according to the control signal to control the switching transistor of the scanning power supply, thereby causing the actual output current signal to track the reference current signal.

[0059] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0060] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0061] 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 them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A parallel quasi-proportional resonant control method for a scanning power supply, characterized in that, include: Obtain the error signal between the reference current signal and the actual output current signal of the scanning power supply; The error signal is input to a parallel quasi-proportional resonant controller, which includes a proportional element and at least two parallel quasi-proportional resonant elements; wherein the resonant center frequencies of the at least two parallel quasi-proportional resonant elements correspond to the fundamental frequency and at least one odd harmonic frequency of the triangular wave characterized by the reference current signal, respectively. The parallel quasi-proportional resonant controller outputs a control signal based on the error signal; A pulse width modulation signal is generated based on the control signal to control the switching transistor of the scanning power supply, thereby causing the actual output current signal to track the reference current signal.

2. The parallel quasi-proportional resonant control method for scanning power supply according to claim 1, characterized in that, The resonant center frequency is determined by Fourier decomposition of the triangular wave represented by the reference current signal.

3. The parallel quasi-proportional resonant control method for scanning power supply according to claim 1 or 2, characterized in that, The at least one odd harmonic frequency includes at least one of the 3rd harmonic frequency, the 5th harmonic frequency, and the 7th harmonic frequency.

4. The parallel quasi-proportional resonant control method for scanning power supply according to claim 1, characterized in that, The parallel quasi-proportional resonant controller is implemented by using the difference equation obtained after discretizing the continuous domain transfer function.

5. The parallel quasi-proportional resonant control method for scanning power supply according to claim 4, characterized in that, The discretization is performed using a bilinear transformation method.

6. The parallel quasi-proportional resonant control method for scanning power supply according to claim 5, characterized in that, The continuous domain transfer function is: ， in, This is the proportional gain coefficient. Let be the resonant gain coefficient of the i-th resonant element. Let be the cutoff frequency of the i-th resonant element. Let be the resonant center frequency of the i-th resonant element, and N be the number of odd harmonics selected. It is a complex frequency variable.

7. The parallel quasi-proportional resonant control method for scanning power supply according to claim 1, characterized in that, The scanning power supply adopts an H-bridge topology.

8. A parallel quasi-proportional resonant control system for scanning power supply, characterized in that, include: The error acquisition module is used to acquire the error signal between the reference current signal and the actual output current signal of the scanning power supply. A controller module, connected to the error acquisition module, is used to implement a parallel quasi-proportional resonant controller. The parallel quasi-proportional resonant controller includes a proportional element and at least two parallel quasi-proportional resonant elements. The resonant center frequencies of the at least two parallel quasi-proportional resonant elements correspond to the fundamental frequency and at least one odd harmonic frequency of the triangular wave represented by the reference current signal, respectively. The parallel quasi-proportional resonant controller outputs a control signal based on the error signal. A PWM generation module, connected to the controller module, is used to generate a pulse width modulation signal according to the control signal to control the switching transistor of the scanning power supply, so that the actual output current signal tracks the reference current signal.

9. The parallel quasi-proportional resonant control system for scanning power supply according to claim 8, characterized in that, The controller module is a digital signal processor or a field-programmable gate array.

10. The parallel quasi-proportional resonant control system for scanning power supply according to claim 8 or 9, characterized in that, The controller module is configured to implement the function of the parallel quasi-proportional resonant controller by executing a difference equation obtained by discretizing a continuous domain transfer function.

Images