A method for controlling the damping of an energy storage converter

Abstract

The application provides a method for controlling the rim damping of an energy storage converter, which is arranged between an AC discharging device and a DC powered device. The method comprises: obtaining an equivalent circuit of the AC discharging device charging the DC powered device through the energy storage converter, the equivalent circuit being used to describe that there is an inductance-capacitance-inductance filter between the AC discharging device and the DC powered device; based on the circuit structure of the equivalent circuit, filtering the actual AC voltage of the AC discharging device and determining the target AC voltage of the energy storage converter by introducing current loop control; and controlling the energy storage converter to output a target DC voltage corresponding to the target AC voltage to the DC powered device, so as to adjust the rim damping of the energy storage converter.

Description

Technical Field

[0001] This application relates to the field of energy storage converter control technology, and in particular to an active damping control method for an energy storage converter. Background Technology

[0002] In the prior art, during the charging process of a diesel generator or the power grid to a battery pack, the energy storage converter is placed between the diesel generator and the battery pack or between the power grid and the battery pack. Due to the filter circuit of the energy storage converter itself and the non-negligible impedance of the diesel generator or the weak power grid, when there is a disturbance in the grid voltage or the voltage delivered by the generator to the energy storage converter, it will affect the voltage received by the inverter circuit of the energy storage converter, thus affecting the stability of the charging process. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide at least one active damping control method for an energy storage converter. By determining that there is an equivalent circuit of an inductive-capacitive-inductive filter between the AC discharge device and the DC power consumption device, and combining the structure of the equivalent circuit, the actual AC voltage of the AC discharge device is filtered and a current loop control is introduced to determine the target AC voltage of the energy storage converter after filtering and current loop control. This method controls the energy storage converter to output a target DC voltage corresponding to the target AC voltage to the DC power consumption device. This solves the technical problem in the prior art where the actual AC voltage of the AC discharge device is disturbed, leading to instability in the charging process, and achieves the technical effect of improving stability.

[0004] This application mainly includes the following aspects:

[0005] In a first aspect, embodiments of this application provide an active damping control method for an energy storage converter, wherein the energy storage converter is disposed between an AC discharge device and a DC power consumption device. The method includes: obtaining an equivalent circuit for the AC discharge device to charge the DC power consumption device through the energy storage converter, the equivalent circuit describing the existence of an inductive-capacitive-inductive filter between the AC discharge device and the DC power consumption device; based on the circuit structure of the equivalent circuit, filtering the actual AC voltage of the AC discharge device and determining a target AC voltage for the energy storage converter by introducing a current loop control; and controlling the energy storage converter to output a target DC voltage corresponding to the target AC voltage to the DC power consumption device to adjust the active damping of the energy storage converter.

[0006] Optionally, the equivalent circuit includes the energy storage converter and the preset inductor of the AC discharge device, wherein the AC side of the energy storage converter is connected to the output terminal of the AC discharge device through the preset inductor, the output terminal provides an output AC voltage, the DC side of the energy storage converter is connected to the DC power supply device, and the actual AC voltage refers to the actual voltage of the output AC voltage after passing through the preset inductor.

[0007] Optionally, the energy storage converter includes an inverter circuit, a filter inductor, and a filter capacitor. The preset inductor, the filter inductor, and the filter capacitor serve as an inductor-capacitor-type filter. One end of the preset inductor serves as an output pin of the AC discharge device. The other end of the preset inductor is connected to one end of the filter capacitor and one end of the filter inductor. The other end of the filter capacitor is connected to another output pin of the AC discharge device. The other ends of the filter inductor and the filter capacitor are connected to the AC side of the inverter circuit. The DC side of the inverter circuit is connected to the DC power supply device. The voltage between one output pin and the other output pin of the AC discharge device serves as the output AC voltage.

[0008] Optionally, the target AC voltage of the energy storage converter is determined by: inputting the desired inductor current and the actual inductor current of the filter inductor into the current loop for proportional-integral control to obtain a pulse-width modulated voltage for the inverter circuit, and using the pulse-width modulated voltage as the input voltage; filtering the actual AC voltage of the AC discharge device to obtain a feedforward voltage; based on the circuit structure of the equivalent circuit, determining the derivation relationship between the actual AC voltage and the target AC voltage according to Kirchhoff's laws, and obtaining the target AC voltage by introducing the input voltage and the feedforward voltage.

[0009] Optionally, the feedforward voltage is obtained by filtering the actual AC voltage of the AC discharge device in any of the following ways: inputting the actual AC voltage to an orthogonal generator to obtain a first fundamental component, and using the first fundamental component as the feedforward voltage; or performing time-delay filtering on the actual AC voltage through a sinusoidal signal phase-locked loop to obtain a second fundamental component, and using the second fundamental component as the feedforward voltage.

[0010] Optionally, the step of filtering the actual AC voltage of the AC discharge device to obtain the feedforward voltage includes: delaying the actual AC voltage by time to obtain a delayed voltage, and filtering the delayed voltage to obtain the feedforward voltage.

[0011] Optionally, the actual inductor current refers to the inductor current flowing through the filter inductor after a time delay, wherein the inductor current of the filter inductor is obtained through the filter inductor and the difference between the actual AC voltage and the target AC voltage.

[0012] Optionally, the AC discharge device includes a weak grid or a generator, and the preset inductor includes the grid inductance of the weak grid or the leakage reactance of the generator.

[0013] Secondly, embodiments of this application also provide an active damping control system for an energy storage converter, the system comprising: an AC discharge device and a DC power consumption device; an energy storage converter disposed between the AC discharge device and the DC power consumption device; and a processor configured to execute the active damping control method for the energy storage converter as described in the first aspect or any possible implementation thereof.

[0014] Thirdly, embodiments of this application also provide an active damping control device for an energy storage converter, wherein the energy storage converter is disposed between an AC discharge device and a DC power consumption device. The device includes: an acquisition module, configured to acquire an equivalent circuit in which the AC discharge device charges the DC power consumption device through the energy storage converter, the equivalent circuit being used to describe the existence of an inductive-capacitive-inductive filter between the AC discharge device and the DC power consumption device; a determination module, configured to, based on the circuit structure of the equivalent circuit, filter the actual AC voltage of the AC discharge device and determine the target AC voltage of the energy storage converter by introducing a current loop control; and a control module, configured to control the energy storage converter to output a target DC voltage corresponding to the target AC voltage to the DC power consumption device, so as to adjust the active damping of the energy storage converter.

[0015] This application provides an approach damping control method for an energy storage converter, wherein the energy storage converter is disposed between an AC discharge device and a DC power consumption device. The method includes: obtaining an equivalent circuit for the AC discharge device to charge the DC power consumption device through the energy storage converter, the equivalent circuit describing the existence of an inductive-capacitive-inductive filter between the AC discharge device and the DC power consumption device; based on the circuit structure of the equivalent circuit, filtering the actual AC voltage of the AC discharge device and determining the target AC voltage of the energy storage converter by introducing a current loop control; and controlling the energy storage converter to output a target DC voltage corresponding to the target AC voltage to the DC power consumption device to adjust the approach damping of the energy storage converter. By identifying an equivalent circuit of an inductive-capacitive-inductive filter between the AC discharge device and the DC power consumption device, and combining the structure of the equivalent circuit, filtering is performed on the actual AC voltage of the AC discharge device, and current loop control is introduced. This allows for the determination of the target AC voltage of the energy storage converter after filtering and current loop control. The energy storage converter is then used to control the output DC voltage corresponding to the target AC voltage to the DC power consumption device. This solves the technical problem in the prior art where disturbances in the actual AC voltage of the AC discharge device lead to instability during the charging process, thus achieving the technical effect of improving stability.

[0016] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A flowchart of an active damping control method for an energy storage converter provided in an embodiment of this application is shown.

[0019] Figure 2 A circuit diagram of the equivalent circuit provided in the embodiments of this application is shown.

[0020] Figure 3 A control block diagram of the active damping control of the energy storage converter provided in an embodiment of this application is shown.

[0021] Figure 4 The Bode plot of the output AC voltage of the AC discharge device provided in the embodiment of this application is shown when there is a disturbance.

[0022] Figure 5 This paper illustrates a functional block diagram of an active damping control device for an energy storage converter provided in an embodiment of this application. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the drawings in this application are for illustrative and descriptive purposes only and are not intended to limit the scope of protection of this application. Furthermore, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be understood that the operations in the flowcharts may not be implemented in sequence, and steps without logical contextual relationships may be reversed or implemented simultaneously. In addition, those skilled in the art, guided by the content of this application, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts.

[0024] Furthermore, the described embodiments are merely some, not all, of the embodiments of this application. The components of the embodiments of this application described and illustrated herein can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0025] In existing technologies, energy storage converters are installed between the diesel generator and the battery pack, or between the power grid and the battery pack. Due to the non-negligible impedance of the energy storage converter, the diesel generator, or the weak power grid, an inductive-capacitive-inductive filter (LCL filter) is formed between the diesel generator and the battery pack, or between the weak power grid and the battery pack. This filter will cause resonance problems, which will affect the voltage received by the inverter circuit of the energy storage converter when there are disturbances in the grid voltage or the voltage delivered by the generator to the energy storage converter, thus affecting the stability of the charging process of the battery pack.

[0026] Based on this, this application provides an active damping control method for an energy storage converter. By determining that an equivalent circuit of an inductive-capacitive-inductive filter exists between the AC discharge device and the DC power consumption device, and considering the structure of the equivalent circuit, the actual AC voltage of the AC discharge device is filtered, and current loop control is introduced. This determines the target AC voltage of the energy storage converter obtained after filtering and current loop control, thereby controlling the energy storage converter to output a target DC voltage corresponding to the target AC voltage to the DC power consumption device. This solves the technical problem in the prior art where disturbances in the actual AC voltage of the AC discharge device lead to instability during the charging process, achieving the technical effect of improving stability. Specifically, as follows:

[0027] Please see Figure 1 , Figure 1 A flowchart illustrating an active damping control method for an energy storage converter provided in an embodiment of this application. Figure 1 As shown in the embodiment of this application, the active damping control method for an energy storage converter includes the following steps:

[0028] S101: Obtain the equivalent circuit of the AC discharge device charging the DC power device through the energy storage converter.

[0029] The energy storage converter is positioned between the AC discharge equipment and the DC power consumption equipment. The AC discharge equipment includes a low-voltage power grid or a generator. In other words, the low-voltage power grid charges the DC power consumption equipment through the energy storage converter, or the generator charges the DC power consumption equipment through the energy storage converter.

[0030] The equivalent circuit describes the existence of an inductive-capacitive filter between the AC discharge device and the DC power supply. Since the AC discharge device and the DC power supply can be equivalently represented by an inductive-capacitive filter, the AC discharge device needs to possess inductance. The AC discharge device can be a weak grid or a generator. A weak grid contains grid inductance. A weak grid refers to a non-ideal grid in practical applications where, under the combined effects of nonlinear loads and line impedance, the grid exhibits slight inductance, and this inductance can no longer be ignored. The generator is generally a diesel generator with leakage reactance.

[0031] Please see Figure 2 , Figure 2 This is a circuit diagram of the equivalent circuit provided in an embodiment of this application. For example... Figure 2 As shown, the equivalent circuit provided in this application embodiment includes: the preset inductance L of the energy storage converter and the AC discharge device 101. gen The AC side of the energy storage converter is connected to the output terminal of the AC discharge device via the preset inductor, and the output terminal provides an output AC voltage U. gridThe DC side of the energy storage converter is connected to the DC power supply 102, and the actual AC voltage U c This refers to the actual voltage across the preset inductor, or in other words, the actual AC voltage U. c It is obtained by collecting the actual voltage of the output AC voltage through a preset inductor.

[0032] The energy storage converter includes an inverter circuit 103 and a filter inductor L. filter and filter capacitor C filter The preset inductor, the filter inductor, and the filter capacitor constitute the inductor-capacitor-inductor type filter. One end of the preset inductor serves as an output pin of the AC discharge device. The other end of the preset inductor is connected to one end of the filter capacitor and one end of the filter inductor. The other end of the filter capacitor is connected to another output pin of the AC discharge device. The other ends of the filter inductor and the filter capacitor are connected to the AC side of the inverter circuit. The DC side of the inverter circuit is connected to the DC power supply device. The voltage between one output pin and the other output pin of the AC discharge device is the output AC voltage.

[0033] Among them, the output AC voltage U of the AC discharge equipment grid By pre-setting inductance L gen Provide the actual AC voltage U to the energy storage converter c Actual AC voltage U c The voltage is equivalent to the filter capacitor C of the energy storage converter. filter The voltage across the terminals, the actual AC voltage U c The filter inductor L of the energy storage converter filter Obtain the target AC voltage U of the energy storage converter pcs The target AC voltage is converted into DC voltage through an inverter circuit, which is then used as the target DC voltage to charge DC electrical equipment.

[0034] Furthermore, the output AC current I of the AC discharge device out By pre-setting inductance L gen Flow into filter capacitor C filter and filter inductor L filter Flow through filter inductor L filter The inductor current is labeled I. pcs Flow through filter capacitor C filter The capacitor current is labeled as I c .

[0035] Specifically, the inverter circuit is used to convert alternating current (AC) into direct current (DC). It includes multiple switching transistors, and the conversion is achieved by closing or opening these transistors. Furthermore, since the AC discharge device includes a weak grid or a generator, the preset inductance includes the grid inductance of the weak grid or the leakage reactance of the generator.

[0036] S102: Based on the circuit structure of the equivalent circuit, the actual AC voltage of the AC discharge device is filtered and a current loop control is introduced to determine the target AC voltage of the energy storage converter.

[0037] Specifically, the target AC voltage of the energy storage converter is determined as follows: the desired inductor current and the actual inductor current of the filter inductor are input to the current loop for proportional-integral control to obtain a pulse-width modulated voltage for the inverter circuit, and the pulse-width modulated voltage is used as the input voltage; the actual AC voltage of the AC discharge device is filtered to obtain a feedforward voltage; based on the circuit structure of the equivalent circuit, the derivation relationship between the actual AC voltage and the target AC voltage is determined according to Kirchhoff's laws, and the target AC voltage is obtained by introducing the input voltage and the feedforward voltage.

[0038] Please see Figure 3 , Figure 3 This is a control block diagram for the active damping control of the energy storage converter provided in an embodiment of this application. Figure 3 As shown, the desired inductor current of the filter inductor is... and actual inductor current The input is fed into the current loop for proportional-integral (PI) control, resulting in a pulse-width modulated voltage U for the inverter circuit. piout And the actual AC voltage U of the AC discharge equipment c Filtering is performed to obtain the feedforward voltage U c ′ The pulse width modulated voltage U piout and feedforward voltage U c ′ The sum of these values ​​serves as the target AC voltage U of the energy storage converter. pcs This allows for the acquisition of a more stable target AC voltage U. pcs This allows for the acquisition of a more stable actual AC voltage U. c In the equivalent circuit structure, the actual AC voltage U of the AC discharge device... c The target AC voltage U of the energy storage converter pcs The voltage difference is equal to the filter inductance L filter The voltage on both sides, i.e. Flow filter inductor L filter Inductor current I pcs Equal to the flow into the preset inductance Lgen Output AC current I out and the inflow filter capacitor C filter The capacitor current I c The sum of, i.e., I out =I c +I pcs Furthermore, the voltage across the filter capacitor is equal to the actual AC voltage U of the AC discharge device. c ,Right now Furthermore, the output AC voltage U of the AC discharge device grid Equal to the actual AC voltage U c With preset inductance L gen The sum of the voltages across the inductor terminals, i.e.

[0039] The step of filtering the actual AC voltage of the AC discharge device to obtain the feedforward voltage includes: delaying the actual AC voltage by time to obtain a delayed voltage, and filtering the delayed voltage to obtain the feedforward voltage.

[0040] In other words, time delay needs to be considered before filtering the actual AC voltage. For example, such as... Figure 3 As shown, considering a time delay of 1.5Ts, where Ts refers to the time required to perform one edge-damped control operation, the voltage being filtered is the voltage before 1.5Ts. This simulates and compensates for the delay phenomenon present in the actual system, helping to optimize the stability, response speed, and anti-interference capability of the control system. Furthermore, the delayed voltage after considering the time delay is filtered to obtain the feedforward voltage.

[0041] Specifically, the feedforward voltage is obtained by filtering the actual AC voltage of the AC discharge device in any of the following ways: inputting the actual AC voltage to an orthogonal generator to obtain a first fundamental component, and using the first fundamental component as the feedforward voltage; or performing time-delay filtering on the actual AC voltage through a sinusoidal signal phase-locked loop to obtain a second fundamental component, and using the second fundamental component as the feedforward voltage.

[0042] For example, the actual AC voltage U of the AC discharge device, taking into account time delay. c The signal is transformed from a three-phase stationary coordinate system to a two-phase stationary coordinate system (αβ coordinate system) using an orthogonal signal generator (OSG), and the α component at the fundamental frequency (typically 50 Hz) is obtained through filtering. This component refers to the actual AC voltage U. c The fundamental frequency component at 50Hz is used as the feedforward voltage for the current loop. Alternatively, the actual AC voltage U of the AC discharge device, considering time delay, can be used. cThe actual AC voltage U is also obtained by performing time-delay filtering using a sinusoidal signal phase-locked loop (PLL). c The fundamental frequency component is at 50Hz, and the fundamental frequency component is Udfil and The product of these two components, Udfil, can be understood as the low-pass filtered component of the direct-axis component of the phase-locked loop output, where θ is the angle obtained by the phase-locked loop, thus providing the feedforward voltage at the fundamental frequency. Furthermore, by modifying the control loop and using filtering, the damping at the resonant point can be effectively increased, thereby improving the desired inductance current of the filter inductor. The output AC voltage U of the AC discharge equipment grid The disturbance affects the target AC voltage U of the energy storage converter. pcs The impact is reduced, and this application does not limit the filtering method, as long as the filtered result is consistent with the actual AC voltage U. c The fundamental frequency component at 50Hz is sufficient.

[0043] The actual inductor current refers to the inductor current flowing through the filter inductor after a time delay, and the inductor current of the filter inductor is obtained by the filter inductor and the difference between the actual AC voltage and the target AC voltage.

[0044] For example, such as Figure 3 As shown, the actual inductor current input to the inverter circuit is obtained by considering a time delay of 1.5Ts for the inductor current flowing through the filter inductor. That is, the inductor current flowing through the filter inductor is taken as the inductor current of the inverter circuit before 1.5Ts, thus obtaining the actual inductor current considering the time delay.

[0045] S103: Control the energy storage converter to output the target DC voltage corresponding to the target AC voltage to the DC power supply equipment, so as to adjust the active damping of the energy storage converter.

[0046] In other words, the target DC voltage, which is converted from the target AC voltage by the inverter circuit, is used as the DC voltage supplied by the energy storage converter to DC electrical equipment during the charging process. This results in a stable target DC voltage, thereby increasing the active damping of the energy storage converter and improving the stability of the charging process.

[0047] For example, the actual AC voltage U of the AC discharge device is not specified. c Filtering is performed. In PFC (Power Factor Correction) control mode, only current loop control is used, taking into account a time delay of 1.5Ts. Figure 3The filtering part in the control block diagram shown is removed. In this case, the small-signal transfer function is derived using MATLAB, and the desired inductor current input in the current loop is analyzed. There are disturbances and the output AC voltage U of the AC discharge device. grid In the presence of disturbances, for the actual AC voltage U c The influence of this was investigated to obtain a Bode plot, which revealed a resonant point with a resonant frequency equal to the preset inductance L. gen and filter capacitor C filter The resulting series resonance. Furthermore, this application reduces the small-signal disturbance to the control circuit at the resonant frequency by sampling and filtering the actual AC voltage of the AC discharge device, thereby effectively suppressing resonance problems in weak grid operation scenarios or when a diesel generator is charging a battery pack.

[0048] Please see Figure 4 , Figure 4 The Bode plot of the output AC voltage of the AC discharge device provided in the embodiments of this application shows a disturbance. For example... Figure 4 As shown in the Bode plot, the red curve corresponds to the curve without filtering, and the blue curve corresponds to the curve with filtering. The horizontal axis represents frequency (in radians per second, rad / s), and the vertical axis represents amplitude (in decibels, dB) and phase (in degrees, deg). An amplitude greater than zero indicates amplified interference, an amplitude less than or equal to zero indicates reduced interference, and an amplitude of zero indicates a gain of 1. Phase represents phase lag. Therefore, when there is disturbance in the output AC voltage of an AC discharge device, the filtered waveform, compared to the unfiltered waveform, exhibits a smaller amplitude, thus reducing interference, while the phase lag gradually increases. Thus, through... Figure 4 This reflects that, in the actual AC voltage U of the AC discharge equipment c Filtering can stabilize the charging voltage and increase the system's anti-interference capability.

[0049] Based on the same application concept, this application also provides an energy storage converter with an active damping control system corresponding to the active damping control method of the energy storage converter provided in the above embodiments. Since the principle of the system in this application is similar to the active damping control method of the energy storage converter in the above embodiments of this application, the implementation of the system can refer to the implementation of the method, and the repeated parts will not be described again.

[0050] The energy storage converter's active damping control system includes: an AC discharge device and a DC power consumption device; an energy storage converter disposed between the AC discharge device and the DC power consumption device; and a processor configured to execute the active damping control method for the energy storage converter as described in any of the above embodiments.

[0051] The processor can choose to use the controller of the energy storage converter itself.

[0052] Based on the same application concept, this application also provides an energy storage converter with an active damping control device corresponding to the active damping control method of the energy storage converter provided in the above embodiments. Since the principle of the device in this application is similar to the active damping control method of the energy storage converter in the above embodiments of this application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be described again.

[0053] like Figure 5 As shown, Figure 5 This application provides a functional block diagram of an active damping control device for an energy storage converter. The active damping control device 20 for the energy storage converter is located between an AC discharge device and a DC power consumption device. The device includes: an acquisition module 201, used to acquire the equivalent circuit of the AC discharge device charging the DC power consumption device through the energy storage converter, the equivalent circuit describing the existence of an inductive-capacitive-inductive filter between the AC discharge device and the DC power consumption device; a determination module 202, used to filter the actual AC voltage of the AC discharge device based on the circuit structure of the equivalent circuit and determine the target AC voltage of the energy storage converter by introducing a current loop control; and a control module 203, used to control the energy storage converter to output a target DC voltage corresponding to the target AC voltage to the DC power consumption device, thereby adjusting the active damping of the energy storage converter.

[0054] Based on the same concept, this application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps of the active damping control method for the energy storage converter provided in the above embodiments.

[0055] Specifically, the storage medium can be a general-purpose storage medium, such as a portable disk or hard disk. When the computer program on the storage medium is run, it can execute the aforementioned active damping control method for the energy storage converter. By determining that there is an equivalent circuit of an inductive-capacitive-inductive filter between the AC discharge device and the DC power consumption device, and combining the structure of the equivalent circuit, the actual AC voltage of the AC discharge device is filtered and a current loop control is introduced to determine the target AC voltage of the energy storage converter after filtering and current loop control. This controls the energy storage converter to output the target DC voltage corresponding to the target AC voltage to the DC power consumption device, thus solving the technical problem in the prior art where the actual AC voltage of the AC discharge device is disturbed, leading to instability in the charging process, and achieving the technical effect of improving stability.

[0056] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems and devices described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division; in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection may be through some communication interfaces; the indirect coupling or communication connection of devices or units may be electrical, mechanical, or other forms.

[0057] 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 units can be selected to achieve the purpose of this embodiment according to actual needs.

[0058] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0059] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, 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 this application. 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.

[0060] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An active damping control method for an energy storage converter, characterized in that, The energy storage converter is installed between the AC discharge equipment and the DC power consumption equipment. The method includes: Obtain the equivalent circuit of the AC discharge device charging the DC power device through the energy storage converter. The equivalent circuit is used to describe the existence of an inductor-capacitor-inductor filter between the AC discharge device and the DC power device. Based on the circuit structure of the equivalent circuit, the actual AC voltage of the AC discharge device is filtered and the target AC voltage of the energy storage converter is determined by introducing current loop control. The energy storage converter is controlled to output a target DC voltage corresponding to the target AC voltage to the DC power supply equipment, so as to adjust the active damping of the energy storage converter.

2. The method according to claim 1, characterized in that, The equivalent circuit includes the energy storage converter and the preset inductor of the AC discharge device. The AC side of the energy storage converter is connected to the output terminal of the AC discharge device via the preset inductor, and the output terminal provides an output AC voltage. The DC side of the energy storage converter is connected to the DC power supply device. The actual AC voltage refers to the actual voltage of the output AC voltage after passing through the preset inductor.

3. The method according to claim 2, characterized in that, The energy storage converter includes an inverter circuit, a filter inductor, and a filter capacitor. The preset inductor, the filter inductor, and the filter capacitor serve as the inductor-capacitor type filter. In this configuration, one end of the preset inductor serves as an output pin of the AC discharge device, and the other end of the preset inductor is connected to one end of the filter capacitor and one end of the filter inductor. The other end of the filter capacitor is connected to another output pin of the AC discharge device. The other ends of the filter inductor and the filter capacitor are connected to the AC side of the inverter circuit, and the DC side of the inverter circuit is connected to the DC power supply device. The voltage between one output pin and the other output pin of the AC discharge device is used as the output AC voltage.

4. The method according to claim 3, characterized in that, The target AC voltage of the energy storage converter is determined in the following manner: The desired inductor current and the actual inductor current of the filter inductor are input to the current loop for proportional-integral control to obtain a pulse width modulation voltage for the inverter circuit, and the pulse width modulation voltage is used as the input voltage. The actual AC voltage of the AC discharge device is filtered to obtain the feedforward voltage; Based on the circuit structure of the equivalent circuit, the derivation relationship between the actual AC voltage and the target AC voltage is determined according to Kirchhoff's laws, and the target AC voltage is obtained by introducing the input voltage and the feedforward voltage.

5. The method according to claim 4, characterized in that, The feedforward voltage obtained by filtering the actual AC voltage of the AC discharge device using any of the following methods: The actual AC voltage is input to the quadrature generator to obtain the first fundamental component, and the first fundamental component is used as the feedforward voltage. The actual AC voltage is filtered without delay using a sinusoidal signal phase-locked loop to obtain the second fundamental component, which is then used as the feedforward voltage.

6. The method according to claim 4, characterized in that, The step of filtering the actual AC voltage of the AC discharge device to obtain the feedforward voltage includes: The actual AC voltage is time-delayed to obtain a delayed voltage, and the delayed voltage is filtered to obtain a feedforward voltage.

7. The method according to claim 4, characterized in that, The actual inductor current refers to the inductor current flowing through the filter inductor, which is obtained by time delay. The inductor current of the filter inductor is obtained by using the filter inductor and the difference between the actual AC voltage and the target AC voltage.

8. The method according to claim 2, characterized in that, The AC discharge device includes a weak grid or a generator, and the preset inductor includes the grid inductance of the weak grid or the leakage reactance of the generator.

9. An active damping control system for an energy storage converter, characterized in that, The system includes: AC discharge equipment and DC electrical equipment; An energy storage converter is disposed between an AC discharge device and a DC power consumption device; The processor is configured to perform the active damping control method for the energy storage converter as described in any one of claims 1 to 8.

10. An active damping control device for an energy storage converter, characterized in that, The energy storage converter is positioned between the AC discharge equipment and the DC power consumption equipment. The device includes: An acquisition module is used to acquire the equivalent circuit of the AC discharge device charging the DC power device through the energy storage converter. The equivalent circuit is used to describe the existence of an inductor-capacitor-inductor filter between the AC discharge device and the DC power device. The determination module is used to filter the actual AC voltage of the AC discharge device based on the circuit structure of the equivalent circuit and determine the target AC voltage of the energy storage converter by introducing current loop control. The control module is used to control the energy storage converter to output a target DC voltage corresponding to the target AC voltage to the DC power supply equipment, so as to adjust the active damping of the energy storage converter.

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