Power feed-forward compensation device and method for pulse power supply of heavy ion accelerator

Abstract

The invention discloses a power feed-forward compensation device and method for a heavy ion accelerator pulse power supply. The power feed-forward compensation device comprises a power supply device, a direct current bus, a DC / DC converter, a pulse load, a bidirectional DC / DC converter and an energy storage unit, the output end of the power supply device is connected with the input end of the DC / DC converter through a DC bus, the output end of the DC / DC converter is connected with the pulse load, the output end of the power supply device is connected with one end of the bidirectional DC / DC converter, and the other end of the bidirectional DC / DC converter is connected with the energy storage unit. The device and the method can counteract the impact on the DC bus and the power grid caused by sudden change of the load power, realize the stability of the voltage of the DC bus, and remarkably improve the electric energy quality of the power grid side.

Description

Technical Field

[0001] This invention belongs to the field of power supply technology and relates to a power feedforward compensation device and method for a pulsed power supply of a heavy ion accelerator. Background Technology

[0002] Heavy ion accelerators, as core devices for cutting-edge scientific research, typically operate in pulsed mode for their ion acceleration process. This operating mode requires the pulsed power supply powering its electromagnets to be able to rapidly and accurately output tens of thousands of amperes of current within microseconds to milliseconds, posing extremely stringent challenges to the power supply system's dynamic response capability, output accuracy, and waveform control.

[0003] To meet the aforementioned requirements for high-precision, low-ripple output, existing technologies generally employ a two-stage power supply architecture of "uncontrolled rectification + DC / DC conversion." In this architecture, the subsequent DC / DC converter (chopper) is responsible for rapid and precise current regulation of the load (electromagnet). However, this architecture has an inherent technical bottleneck: when the load current increases at an extremely high rate, the instantaneous power required by the load increases dramatically. Since the input power of the preceding three-phase uncontrolled rectifier bridge comes from the power grid, its response speed lags far behind this millisecond-level power surge, causing the grid to be unable to provide all the required energy in a timely manner.

[0004] During this transient process, the huge power deficit can only be provided by the supporting capacitor on the DC bus side. The direct consequence is the instantaneous release of the capacitor's stored energy, causing a significant drop and oscillation in the DC bus voltage, such as... Figure 1 As shown. Subsequently, the capacitor draws energy from the grid side to restore the voltage, thereby generating a pulse current on the grid side that lags behind the load current change, as shown. Figure 2 As shown, these periodic and severe power surges not only cause serious voltage dips and waveform distortions on the grid side, but also interfere with other sensitive electrical equipment connected to the same distribution network. This has become a key power quality issue restricting the stable and efficient operation of such large scientific facilities. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a power feedforward compensation device and method for a pulsed power supply of a heavy ion accelerator. This device and method can offset the impact of sudden load power changes on the DC bus and the power grid, stabilize the DC bus voltage, and significantly improve the power quality on the power grid side.

[0006] To achieve the above objectives, the present invention discloses a power feedforward compensation device for a pulsed power supply of a heavy ion accelerator, comprising a power supply unit, a DC bus, a DC / DC converter, a pulsed load, a bidirectional DC / DC converter, and an energy storage unit. The output end of the power supply device is connected with the input end of the DC / DC converter through the DC bus, the output end of the DC / DC converter is connected with the pulse load, the output end of the power supply device is connected with one end of the bidirectional DC / DC converter, and the other end of the bidirectional DC / DC converter is connected with the energy storage unit.

[0007] Further, the input end of the DC / DC converter is connected in parallel with a capacitor.

[0008] Further, a first detector for detecting the input voltage of the DC / DC converter is further included.

[0009] Further, a second detector for detecting the load current of the pulse load is further included.

[0010] Further, a first controller, a first power calculation module, an adder, a second power calculation module, a second controller and a bidirectional DC / DC converter are further included. The output end of the first detector is connected with the input end of the first controller, the output end of the second detector is connected with the input end of the first power calculation module, the output end of the first controller and the output end of the first power calculation module are connected with the input end of the adder, the output end of the adder is connected with the input end of the second power calculation module, the output end of the second power calculation module is connected with the input end of the second controller, and the ground output end of the second controller is connected with the control end of the bidirectional DC / DC converter.

[0011] Further, the first controller is a voltage PI controller.

[0012] The application discloses a power feedforward compensation device for a heavy ion accelerator pulse power supply, which comprises a power supply device, a DC bus, a DC / DC converter, a pulse load, a bidirectional DC / DC converter, an energy storage unit, a first controller, a first power calculation module, an adder, a second power calculation module, a second controller, a bidirectional DC / DC converter, a first detector for detecting the input voltage of the DC / DC converter and a second detector for detecting the load current of the pulse load. The output end of the power supply device is connected with the input end of the DC / DC converter through the DC bus, the output end of the DC / DC converter is connected with the pulse load, the output end of the power supply device is connected with one end of the bidirectional DC / DC converter, and the other end of the bidirectional DC / DC converter is connected with the energy storage unit. The output end of the first detector is connected with the input end of the first controller, the output end of the second detector is connected with the input end of the first power calculation module, the output end of the first controller and the output end of the first power calculation module are connected with the input end of the adder, the output end of the adder is connected with the input end of the second power calculation module, the output end of the second power calculation module is connected with the input end of the second controller, and the ground output end of the second controller is connected with the control end of the bidirectional DC / DC converter.

[0013] The application discloses a power feedforward compensation method for a heavy ion accelerator pulse power supply. The input voltage of the DC / DC converter is detected by the first detector U dc The load current of the pulse load is detected by the second detector i o ; The first controller calculates the deviation between the input voltage of the DC / DC converter U dc And a preset voltage, and generates a correction power P pi According to the deviation The first power calculation module calculates the change rate of the load current i o Based on the load current by a differential and filtering algorithm di o / dt And generates a feedforward power according to the change rate of the load current di o / dt P ff ; The feedforward power P ff And the correction power P pi Are added by the adder to obtain a total compensation power instruction P ref ; The second power calculation module divides the total compensation power instruction P ref By U dc And generates an output current instruction of the compensation device according to the calculation result I ref ; The second controller generates a PWM control signal according to the output current instruction of the compensation device I ref And controls the bidirectional DC / DC converter through the PWM control signal.

[0014] ​Further, the input end of the DC / DC converter is connected in parallel with a capacitor.

[0015] Further, the first controller is a voltage PI controller.

[0016] The application has the following beneficial effects: The power feedforward compensation device and method for the heavy ion accelerator pulse power supply in the specific operation are based on the input voltage of the DC / DC converter U dc and the load current of the pulse load i o The feedforward power P ff and the correction power P pi generate the output current instruction of the compensation device I ref According to the output current instruction of the compensation device I ref generate the PWM control signal, and control the bidirectional DC / DC converter through the PWM control signal, realize the complete offset of the disturbance power, can greatly inhibit the drop and oscillation of the DC bus voltage, and effectively smooth the impact current of the grid side, realize the stability of the DC bus voltage, and significantly improve the power quality of the grid side. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the description of the embodiments of the present application. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0018] Figure 1 The load power rises capacitor voltage change graph; Figure 2 The influence graph of the magnet power excitation process on the grid connection point; Figure 3 The structural diagram of the application.

[0019] Among them, 1 is a DC / DC converter, 2 is a pulse load, 3 is a first controller, 4 is an adder, 5 is a first power calculation module, 6 is a second power calculation module, 7 is a second controller, 8 is a bidirectional DC / DC converter, 9 is an energy storage unit. DETAILED DESCRIPTION

[0020] Clearly, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort are within the protection scope of the present application.

[0021] In the description of the present application, it should be understood that the terms "comprising" and "including" indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0022] It should also be understood that the terms used in the present application specification are only for the purpose of describing particular embodiments and are not intended to limit the present application. As used in the present application specification and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0023] It should be further understood that the term "and / or" used in the present application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations thereof, and includes these combinations, for example, A and / or B can mean the existence of A alone, the existence of B alone, and the existence of both A and B. In addition, the character " / " in the present application generally represents an "or" relationship between the front and rear associated objects.

[0024] It should be understood that although the terms first, second, third, etc. can be used in the embodiments of the present application to describe preset ranges, etc., these preset ranges should not be limited to these terms. These terms are only used to distinguish the preset ranges from each other. For example, the first preset range can also be referred to as the second preset range, and similarly, the second preset range can also be referred to as the first preset range without departing from the scope of the embodiments of the present application.

[0025] Depending on the context, the word "if" as used herein can be interpreted to mean "when" or "while" or "in response to determining" or "in response to detecting". Similarly, the phrase "if determined" or "if detecting (a stated condition or event)" can be interpreted to mean "when determined" or "in response to determining" or "when detecting (a stated condition or event)" or "in response to detecting (a stated condition or event)", depending on the context.

[0026] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0027] Various structural schematic diagrams according to the disclosed embodiments of the present application are shown in the drawings. These diagrams are not drawn to scale, in which some details are enlarged for the purpose of clear expression, and some details can be omitted. The shapes of various regions, layers and their relative sizes and positional relationships shown in the drawings are only exemplary, and in actuality, there can be deviations due to manufacturing tolerances or technical limitations, and a person skilled in the art can additionally design regions / layers with different shapes, sizes and relative positions according to actual needs.

[0028] With reference to Figure 3 The power feedforward compensation device for the pulsed power supply of the heavy ion accelerator according to the present application comprises a power supply device, a DC bus, a DC / DC converter 1, a pulsed load 2, a first controller 3, a summer 4, a first power calculation module 5, a second power calculation module 6, a second controller 7, a bidirectional DC / DC converter 8 and an energy storage unit 9. The output end of the power supply device is connected with the input end of the DC / DC converter 1 through the DC bus, the output end of the DC / DC converter 1 is connected with the pulsed load 2, and one end of the bidirectional DC / DC converter 8 is connected with the output end of the power supply device, and the other end of the bidirectional DC / DC converter 8 is connected with the energy storage unit 9.

[0029] In the embodiment, the input end of the DC / DC converter 1 is connected in parallel with a capacitor.

[0030] The first detector is connected to the input of the first controller 3, and the output of the second detector is connected to the input of the first power calculation module 5, the output of the first controller 3 and the output of the first power calculation module 5 are connected to the input of the adder 4, the output of the adder 4 is connected to the input of the second power calculation module 6, the output of the second power calculation module 6 is connected to the input of the second controller 7, and the ground output of the second controller 7 is connected to the control end of the bidirectional DC / DC converter 8.

[0031] The power feedforward compensation method for the heavy ion accelerator pulse power supply comprises the following steps: The input voltage of the DC / DC converter 1 is detected by the first detector U dc The load current of the pulse load 2 is detected by the second detector i o .

[0032] The first controller 3 calculates the deviation between the input voltage of the DC / DC converter 1 and the preset voltage U dc , and generates a correction power P according to the deviation pi to eliminate the feedforward error and the system steady-state error, and the first controller 3 is a voltage PI controller.

[0033] The first power calculation module 5 calculates the change rate of the load current based on the load current i o by a differential and filtering algorithm di o / dt , and calculates the feedforward power according to the change rate of the load current di o / dt P ff .

[0034] The feedforward power and the correction power P are added by the adder 4 P ff to obtain a total compensation power instruction pi P ref .

[0035] The second power calculation module 6 divides the total compensation power instruction by P ref U dc ​​​and generates an output current command of the compensation device according to the calculation result I ref .

[0036] The second controller 7 generates a PWM control signal according to the output current command of the compensation device I ref and controls the bidirectional DC / DC converter 8 according to the PWM control signal to eliminate the feedforward error and the system steady-state error.

[0037] The present application drives the bidirectional DC / DC converter 8 to perform accurate power feedforward by calculating the dynamic power of the impact load in real time, thereby eliminating the impact on the DC bus and the power grid caused by sudden changes in load power at the source, achieving the stability of the DC bus voltage, and significantly improving the power quality of the power grid side.

[0038] The present application is based on real-time monitoring of the load characteristics (i.e. load current i o and its rate of change di o / dt The present application predicts and calculates the instantaneous disturbance power that causes system power imbalance in advance, and then generates a compensation command to drive a bidirectional DC / DC converter 8 connected in parallel to the DC bus to act, so that the device actively and synchronously provides or absorbs the disturbance power, thereby achieving instantaneous balance of system power.

[0039] The present application has the following characteristics: Stepwise improvement of response speed: The generation of the compensation command in the present application is ahead of the drop of the DC bus voltage, achieving millisecond-level or even microsecond-level instantaneous response, which fundamentally solves the problem that traditional feedback control cannot compensate for rapid impact due to detection and calculation delay.

[0040] High compensation accuracy and significant effect: Compensation is based on an accurate physical model ( P = L * i * di / dt ), which can theoretically achieve complete cancellation of the disturbance power. In practical applications, it can greatly suppress the drop and oscillation of the DC bus voltage and effectively smooth the impact current on the power grid side.

[0041] Relieve the pressure of closed-loop control and improve system stability: Power feedforward undertakes most of the dynamic compensation tasks, so that the outer voltage PI controller only needs to handle the small part of error and system loss left after feedforward. This makes the voltage loop parameter design more relaxed, the system robustness stronger, and the stability better.

[0042] Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.

[0043] It is to be understood that the application is not limited to the precise construction herein described and as shown in the attached drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope of the application. The scope of the application is limited only by the claims that follow.

[0044] The above description is only the preferred embodiment of the present application, not any limitation to the present application, any simple modification, change and equivalent structure change of the above embodiment according to the technical essence of the present application are still within the protection scope of the technical solution of the present application.

Claims

1. A power feedforward compensation device for a pulsed power supply in a heavy ion accelerator, characterized in that, It includes a power supply unit, a DC bus, a DC / DC converter (1), a pulse load (2), a bidirectional DC / DC converter (8), and an energy storage unit (9). The output of the power supply is connected to the input of the DC / DC converter (1) via the DC bus. The output of the DC / DC converter (1) is connected to the pulse load (2). The output of the power supply is connected to one end of the bidirectional DC / DC converter (8). The other end of the bidirectional DC / DC converter (8) is connected to the energy storage unit (9).

2. The power feedforward compensation device for a pulsed power supply of a heavy ion accelerator according to claim 1, characterized in that, A capacitor is connected in parallel at the input terminal of the DC / DC converter (1).

3. The power feedforward compensation device for a pulsed power supply of a heavy ion accelerator according to claim 1, characterized in that, It also includes a first detector for detecting the input voltage of the DC / DC converter (1).

4. The power feedforward compensation device for a pulsed power supply of a heavy ion accelerator according to claim 3, characterized in that, It also includes a second detector for detecting the load current of the pulse load (2).

5. The power feedforward compensation device for a pulsed power supply of a heavy ion accelerator according to claim 4, characterized in that, It also includes a first controller (3), a first power calculation module (5), an adder (4), a second power calculation module (6), a second controller (7), and a bidirectional DC / DC converter (8); The output of the first detector is connected to the input of the first controller (3), the output of the second detector is connected to the input of the first power calculation module (5), the output of the first controller (3) and the output of the first power calculation module (5) are connected to the input of the adder (4), the output of the adder (4) is connected to the input of the second power calculation module (6), the output of the second power calculation module (6) is connected to the input of the second controller (7), and the ground output of the second controller (7) is connected to the control terminal of the bidirectional DC / DC converter (8).

6. The power feedforward compensation device for a pulsed power supply of a heavy ion accelerator according to claim 1, characterized in that, The first controller (3) is a voltage PI controller.

7. A power feedforward compensation device for a pulsed power supply in a heavy ion accelerator, characterized in that, It includes a power supply unit, a DC bus, a DC / DC converter (1), a pulse load (2), a bidirectional DC / DC converter (8), an energy storage unit (9), a first controller (3), a first power calculation module (5), an adder (4), a second power calculation module (6), a second controller (7), a bidirectional DC / DC converter (8), a first detector for detecting the input voltage of the DC / DC converter (1), and a second detector for detecting the load current of the pulse load (2); The output terminal of the power supply device is connected to the input terminal of the DC / DC converter (1) via the DC bus. The output terminal of the DC / DC converter (1) is connected to the pulse load (2). The output terminal of the power supply device is connected to one end of the bidirectional DC / DC converter (8). The other end of the bidirectional DC / DC converter (8) is connected to the energy storage unit (9). The output of the first detector is connected to the input of the first controller (3), the output of the second detector is connected to the input of the first power calculation module (5), the output of the first controller (3) and the output of the first power calculation module (5) are connected to the input of the adder (4), the output of the adder (4) is connected to the input of the second power calculation module (6), the output of the second power calculation module (6) is connected to the input of the second controller (7), and the ground output of the second controller (7) is connected to the control terminal of the bidirectional DC / DC converter (8).

8. A power feedforward compensation method for a pulsed power supply in a heavy ion accelerator, characterized in that, The power feedforward compensation device for a pulsed power supply for a heavy ion accelerator according to claim 7 includes the following steps: The input voltage of the DC / DC converter (1) is detected by the first detector. U dc The load current of the pulse load (2) is detected by the second detector. i o ; The first controller (3) calculates the input voltage of the DC / DC converter (1). U dc The deviation from the preset voltage is used to generate a correction power P. pi ; The first power calculation module (5) is based on the load current. i o The rate of change of load current is calculated using differentiation and filtering algorithms. di o / dt Then, based on the rate of change of the load current di o / dt Calculate feedforward power P ff ; The feedforward power is processed by adder (4). P ff With corrected power P pi Add them together to obtain the total compensation power command. P ref ; The second power calculation module (6) will use the total compensation power command P ref Divide by U dc Based on the calculation results, the output current command of the compensation device is generated. I ref ; The second controller (7) responds to the output current command of the compensation device. I ref A PWM control signal is generated, and the bidirectional DC / DC converter (8) is controlled by the PWM control signal.

9. The power feedforward compensation method for a pulsed power supply in a heavy ion accelerator according to claim 8, characterized in that, A capacitor is connected in parallel at the input terminal of the DC / DC converter (1).

10. The power feedforward compensation method for a pulsed power supply in a heavy ion accelerator according to claim 9, characterized in that, The first controller (3) is a voltage PI controller.

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