Method and device for calculating active damping in wind power generation system

Abstract

The invention relates to the technical field of electronic circuits, in particular to a method and device for calculating active damping in a wind power generation system, and the method comprises the steps: constructing an active damping transfer function suitable for a single-ring network construction type permanent magnet synchronous wind power generation system based on a control strategy of a single-ring network construction type inverter and a control strategy of the permanent magnet synchronous wind power generation system; calculating a proportionality coefficient and a time constant based on a system parameter meeting a first preset condition, a system characteristic quantity meeting a second preset condition and a stability index meeting a third preset condition in the single-ring network construction type permanent magnet synchronous wind power generation system; and quantifying the active damping transfer function according to the proportionality coefficient and the time constant to obtain an active damping compensation transfer function. Therefore, the problems that in the prior art, due to the fact that the resonance dynamic and non-minimum phase characteristics of the LCL filter and the influence of RAP control on the LCL resonance mode are not considered, the high-frequency resonance dominant instability phenomenon is likely to occur, and in addition, necessary theoretical support is lacked are solved.

Description

Technical Field

[0001] The present application relates to the technical field of electronic circuits, and particularly to a calculation method and device for active damping in a wind power generation system. Background Art

[0002] With the development of renewable energy systems, grid-forming inverters play a key grid connection control function in permanent magnet synchronous wind power generation systems. The current grid-forming inverter architectures are mainly divided into two categories: multi-loop control and single-loop control. The former adopts an architecture that combines an outer-loop power control and an inner-loop voltage / current control, while the latter directly generates a voltage reference signal through a single power control. Although the single-loop structure sacrifices the direct control ability of the inner loop for voltage and current, its simple control structure and potential small-signal stability advantages have attracted much attention.

[0003] In related technologies, at the control design level, global optimization can be carried out through advanced control methods such as H∞ synthesis, or the system can be decoupled into independent control loops based on reasonable assumptions. For a permanent magnet synchronous wind power generation system, when the machine-side converter controls the DC voltage and the grid-side converter adopts a grid-forming control, the DC dynamics and the AC-side control loop exhibit decoupling characteristics. On the AC side, the decoupling design of the active power and reactive power control loops can be achieved through virtual reactance technology.

[0004] However, in related technologies, for a single-loop grid-forming system, the influence of the LCL filter resonance dynamics is generally ignored, and the non-minimum phase characteristics of the system and the influence of RAP (Reactive Power) control on the LCL resonance mode are not fully considered, resulting in the possibility of instability phenomena dominated by high-frequency resonance even when the low-frequency power loop is stable. In addition, there is a lack of theoretical support for the compatibility of certain parameter design criteria and control structures, and improvement is urgently needed. Summary of the Invention

[0005] The present application provides a calculation method and device for active damping in a wind power generation system to solve the problems in related technologies that for a single-loop grid-forming system, due to the lack of consideration of the LCL filter resonance dynamics, non-minimum phase characteristics, and the influence of RAP control on the LCL resonance mode, instability phenomena dominated by high-frequency resonance are likely to occur. In addition, there is also a lack of theoretical support for the compatibility of certain parameter design criteria and control structures in the single-loop grid-forming system.

[0006] An embodiment of the first aspect of the present application provides a method for calculating active damping in a wind power generation system, including the following steps: Based on the control strategy of a single-loop grid-forming inverter and the control strategy of a permanent magnet synchronous wind power generation system, construct an active damping transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system; Based on the system parameters that meet the first preset condition, the system characteristic quantities that meet the second preset condition, and the stability index that meets the third preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system, calculate the proportional coefficient and time constant in the active damping transfer function; Quantify the active damping transfer function according to the proportional coefficient and the time constant to obtain an active damping compensation transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system, which is used to calculate the active damping in the single-loop grid-forming permanent magnet synchronous wind power generation system.

[0007] Optionally, in an embodiment of the present application, the step of constructing an active damping transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system based on the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system includes: Based on the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system, determine the voltage signal acting on the filter capacitor in the single-loop grid-forming permanent magnet synchronous wind power generation system; Construct the active damping transfer function according to the voltage signal.

[0008] Optionally, in an embodiment of the present application, the system parameters that meet the first preset condition and the system characteristic quantities that meet the second preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system include: Obtain the maximum reactive power control bandwidth and the minimum short-circuit ratio in the single-loop grid-forming permanent magnet synchronous wind power generation system; Based on the maximum reactive power control bandwidth and the minimum short-circuit ratio, determine the operating condition information; Based on the operating condition information, calculate the system characteristic quantities in the active damping transfer function; Obtain the rated resonant frequency of the LCL filter in the single-loop grid-forming permanent magnet synchronous wind power generation system, and obtain the system parameters according to the rated resonant frequency of the LCL filter.

[0009] Optionally, in an embodiment of the present application, the step of calculating the proportional coefficient and time constant in the active damping transfer function based on the system parameters that meet the first preset condition, the system characteristic quantities that meet the second preset condition, and the stability index that meets the third preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system includes: Based on the system characteristic quantities and the stability index, calculate the proportional coefficient in the active damping transfer function; Based on the system parameters, calculate the time constant.

[0010] Optionally, in an embodiment of the present application, the expression of the active damping transfer function may be, but is not limited to:

[0011]

[0012] where s is a complex number, and k d is the proportional coefficient in the active damping, and T d is the time constant.

[0013] An embodiment of the second aspect of the present application provides a calculation device for active damping in a wind power generation system, including: a construction module, configured to construct an active damping transfer function applicable to a single-loop grid-forming permanent magnet synchronous wind power generation system based on the control strategy of a single-loop grid-forming inverter and the control strategy of a permanent magnet synchronous wind power generation system; a calculation module, configured to calculate the proportional coefficient and the time constant in the active damping transfer function based on system parameters satisfying a first preset condition, system characteristic quantities satisfying a second preset condition, and a stability index satisfying a third preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system; a generation module, configured to quantify the active damping transfer function according to the proportional coefficient and the time constant to obtain an active damping compensation transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system, for calculating the active damping in the single-loop grid-forming permanent magnet synchronous wind power generation system.

[0014] Optionally, in an embodiment of the present application, the construction module includes: a first determination unit, configured to determine a voltage signal acting on a filter capacitor in the single-loop grid-forming permanent magnet synchronous wind power generation system based on the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system; a construction unit, configured to construct the active damping transfer function according to the voltage signal.

[0015] Optionally, in an embodiment of the present application, the calculation module includes: an acquisition unit, configured to acquire the maximum reactive power control bandwidth and the minimum short-circuit ratio in the single-loop grid-forming permanent magnet synchronous wind power generation system; a second determination unit, configured to determine the operating condition information based on the maximum reactive power control bandwidth and the minimum short-circuit ratio; a first calculation unit, configured to calculate the system characteristic quantities in the active damping transfer function based on the operating condition information; a generation unit, configured to acquire the rated resonance frequency of the LCL filter in the single-loop grid-forming permanent magnet synchronous wind power generation system, and obtain the system parameters according to the rated resonance frequency of the LCL filter.

[0016] Optionally, in an embodiment of the present application, the calculation module, a second calculation unit, configured to calculate the proportional coefficient in the active damping transfer function based on the system characteristic quantities and the stability index; a third calculation unit, configured to calculate the time constant based on the system parameters.

[0017] Optionally, in an embodiment of the present application, the expression of the active damping transfer function may be, but is not limited to:

[0018]

[0019] Among them, s is a complex number, k d is the proportionality coefficient in active damping, T d is the time constant.

[0020] A third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method for calculating active damping in a wind power generation system as described in the above embodiment.

[0021] A fourth aspect of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, which, when executed by a processor, implements the above method for calculating active damping in a wind power generation system.

[0022] A fifth aspect of the present application provides a computer program product, including a computer program, which, when executed, implements the above method for calculating active damping in a wind power generation system.

[0023] The embodiment of the present application can construct an active damping transfer function suitable for a single-ring meshed permanent magnet synchronous wind power generation system based on the control strategy of a single-ring meshed inverter and the control strategy of a permanent magnet synchronous wind power generation system, and then calculate the proportional coefficient and time constant in the active damping transfer function according to the system parameters that meet the first preset condition, the system characteristic quantity that meets the second preset condition, and the stability index that meets the third preset condition in the single-ring meshed permanent magnet synchronous wind power generation system, and then quantify the active damping transfer function, and obtain the active damping compensation transfer function suitable for the single-ring meshed permanent magnet synchronous wind power generation system, and realize the calculation of active damping in the single-ring meshed permanent magnet synchronous wind power generation system. By adding the active damping control strategy of filter capacitor voltage feedback to the single-ring meshed permanent magnet synchronous wind power generation system, the influence of the single-ring control system on the LCL resonance is fully considered, and the high-frequency resonance is effectively suppressed to improve the system stability. Thus, the problem in the related art that for a single-ring meshed system, the high-frequency resonance-dominated instability phenomenon is prone to occur due to the failure to consider the dynamic and non-minimum phase characteristics of the LCL filter resonance and the influence of RAP control on the LCL resonance mode is solved. In addition, there is a lack of theoretical support for the compatibility of certain parameter design criteria and control structures in single-ring network systems.

[0024] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description of embodiments in conjunction with the accompanying drawings, where:

[0026] Figure 1 FIG. 4 is a flowchart of a method for calculating active damping in a wind power generation system according to an embodiment of the present application;

[0027] Figure 2 FIG. 5 is a schematic structural diagram of a permanent magnet synchronous wind power generation system with an LCL filter under a single-loop network-forming inverter control strategy according to an embodiment of the present application;

[0028] Figure 3 FIG. 6 is a schematic diagram of a control framework of a permanent magnet synchronous wind power generation system according to an embodiment of the present application;

[0029] Figure 4 FIG. 7 is a schematic diagram of a framework of an active damping control link according to an embodiment of the present application;

[0030] Figure 5 FIG. 8 is a schematic diagram of design characteristic values based on the most unfavorable working conditions according to an embodiment of the present application;

[0031] Figure 6 FIG. 9 is a schematic structural diagram of a nine-bus system of a single-loop network-forming permanent magnet synchronous wind power generation system according to an embodiment of the present application;

[0032] Figure 7 FIG. 10 is a schematic diagram of simulation results according to the parameters listed in Table 1 in an embodiment of the present application;

[0033] Figure 8 FIG. 11 is a schematic diagram of simulation results when L g = 0.5 p.u. is set according to Table 1 in an embodiment of the present application;

[0034] Figure 9 FIG. 12 is a schematic block diagram of a device for calculating active damping in a wind power generation system according to an embodiment of the present application;

[0035] Figure 10 FIG. 13 is a schematic structural diagram of an electronic device according to an embodiment of the present application. Detailed Embodiments

[0036] Embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present application and should not be construed as limiting the present application.

[0037] The following describes the calculation method and device of active damping in the wind power generation system of the embodiment of the present application with reference to the accompanying drawings. For the single-ring network system mentioned in the above background technology, since the LCL filter resonant dynamics and non-minimum phase characteristics and the influence of RAP control on the LCL resonant mode are not considered, high-frequency resonance-dominated instability phenomenon is prone to occur. In addition, there is a problem that there is a lack of theoretical support for the compatibility of certain parameter design criteria and control structures in single-loop grid-type systems. The present application provides a method for calculating active damping in a wind power generation system. In this method, an active damping transfer function suitable for a single-loop grid-type permanent magnet synchronous wind power generation system can be constructed based on the control strategy of the single-loop grid-type inverter and the control strategy of the permanent magnet synchronous wind power generation system. Then, according to the system parameters that meet the first preset condition, the system characteristic quantities that meet the second preset condition, and the stability index that meets the third preset condition in the single-loop grid-type permanent magnet synchronous wind power generation system, the proportional coefficient and the time constant in the active damping transfer function are calculated, and then the active damping transfer function is quantified to obtain an active damping compensation transfer function suitable for the single-loop grid-type permanent magnet synchronous wind power generation system, thereby realizing the calculation of active damping in the single-loop grid-type permanent magnet synchronous wind power generation system. By adding an active damping control strategy of filter capacitor voltage feedback in the single-loop grid-type permanent magnet synchronous wind power generation system, the influence of the single-loop control system on the LCL resonance is fully considered, high-frequency resonance is effectively suppressed, and system stability is improved. This solves the problem in the related art that, for single-ring meshing systems, the high-frequency resonance-dominated instability phenomenon is prone to occur due to the failure to consider the dynamic and non-minimum phase characteristics of the LCL filter resonance and the influence of RAP control on the LCL resonance mode. In addition, there is a lack of theoretical support for the compatibility of certain parameter design criteria and control structures in single-ring meshing systems.

[0038] Specifically, Figure 1 The present invention is a flowchart of a method for calculating active damping in a wind power generation system according to an embodiment of the present application.

[0039] like Figure 1 As shown, the calculation method of active damping in the wind power generation system includes the following steps:

[0040] In step S101, based on the control strategy of the single-ring grid-type inverter and the control strategy of the permanent magnet synchronous wind power generation system, an active damping transfer function suitable for the single-ring grid-type permanent magnet synchronous wind power generation system is constructed. The expression of the active damping transfer function can be but is not limited to:

[0041]

[0042] Among them, s is a complex number, k d is the proportionality coefficient in active damping, T d is the time constant.

[0043] In some embodiments, the embodiments of the present application can be combined with Figure 2 the permanent magnet synchronous wind power generation system with an LCL filter under the single-loop grid-forming inverter control strategy shown in Figure 3 and on the basis of the control strategy of the permanent magnet synchronous wind power generation system shown in Figure 4 add an active damping control link shown in ad (s) acts on the filtered capacitor voltage feedback signal v abc , and its expression can be but is not limited to:

[0044]

[0045] where s is a complex number, which is the parameter of the Laplace transform, and k d is the proportional coefficient in the active damping, and T d is the time constant. This transfer function ensures that oscillations can be effectively suppressed at the resonant frequency while avoiding adverse effects on other frequency ranges of the system.

[0046] Optionally, in an embodiment of the present application, based on the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system, an active damping transfer function suitable for the single-loop grid-forming permanent magnet synchronous wind power generation system is constructed, including: based on the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system, determining the voltage signal acting on the filtered capacitor in the single-loop grid-forming permanent magnet synchronous wind power generation system; constructing an active damping transfer function according to the voltage signal.

[0047] In some embodiments, when constructing an active damping transfer function suitable for the single-loop grid-forming permanent magnet synchronous wind power generation system, the embodiments of the present application can first determine the voltage signal acting on the filtered capacitor in the single-loop grid-forming permanent magnet synchronous wind power generation system according to the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system, and then construct an active damping transfer function using this voltage signal.

[0048] In step S102, based on the system parameters that meet the first preset condition, the system characteristic quantities that meet the second preset condition, and the stability index that meet the third preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system, calculate the proportional coefficient and the time constant in the active damping transfer function.

[0049] It can be understood that in the embodiments of the present application, the system parameters can be calculated using the rated resonance frequency of the LCL filter, and then the system parameters that meet the first preset condition can be obtained. Among them, the first preset condition can be set by those skilled in the art according to the actual situation, and the present application does not make specific limitations.

[0050] Furthermore, in the embodiments of the present application, the system characteristic quantities can include, but are not limited to, the minimum reactive power mode poles and the maximum line inductance value, etc., and the present application does not make specific limitations. Then, the system characteristic quantities that meet the second preset condition can be obtained in the embodiments of the present application. Among them, the second preset condition can be set by those skilled in the art according to the actual situation, and the present application does not make specific limitations.

[0051] In addition, the embodiments of the present application can obtain a stability index that meets the third preset condition, thereby ensuring that the designed active damping transfer function has sufficient robustness. Among them, the third preset condition can be set by those skilled in the art according to the actual situation, and the present application does not make specific limitations.

[0052] Exemplarily, in the embodiments of the present application, the negative real part value of the key resonance mode can be less than -10 to ensure that the LCL resonance can still be effectively suppressed under various uncertain disturbances.

[0053] As a possible implementation manner, the embodiments of the present application can calculate the proportional coefficient and time constant in the active damping transfer function through the system parameters that meet the first preset condition, the system characteristic quantities that meet the second preset condition, and the stability index that meets the third preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system.

[0054] Optionally, in an embodiment of the present application, the system parameters that meet the first preset condition and the system characteristic quantities that meet the second preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system include: obtaining the maximum reactive power control bandwidth and the minimum short-circuit ratio in the single-loop grid-forming permanent magnet synchronous wind power generation system; determining the operating condition information based on the maximum reactive power control bandwidth and the minimum short-circuit ratio; calculating the system characteristic quantities in the active damping transfer function based on the operating condition information; obtaining the rated resonance frequency of the LCL filter in the single-loop grid-forming permanent magnet synchronous wind power generation system, and obtaining the system parameters according to the rated resonance frequency of the LCL filter.

[0055] It can be understood that in the embodiments of the present application, the bandwidth is an important index to measure the dynamic response ability of the system, and is usually used to measure the frequency range in which the system can effectively follow the change of the input signal. The maximum reactive power control bandwidth can be understood as the highest frequency at which the system can effectively respond in reactive power control.

[0056] Furthermore, the short-circuit ratio in the embodiments of the present application is an important parameter for measuring the electrical strength of the connection point between the power station and the power grid, and can be understood as the ratio of the short-circuit capacity at a specific point in the system to the rated capacity of the grid-connected units of the power station. The minimum short-circuit ratio can be the short-circuit ratio under the minimum operating mode of the system, reflecting the lowest impact of the power grid on the voltage stability and fault support ability of the new energy generating units.

[0057] Furthermore, the embodiments of the present application can determine the operating condition information based on the maximum reactive power control bandwidth and the minimum short-circuit ratio in the single-loop grid-forming permanent magnet synchronous wind power generation system. That is, the operating condition information is not obtained based on the active damping transfer function, but the active damping transfer function can be applicable under any operating conditions.

[0058] Exemplarily, in the embodiments of the present application, the RAP control bandwidth and the grid-side inductor L g have an important impact on the resonance stability of the system. When the RAP control bandwidth or L g is relatively large, the resonance mode of the system is more likely to tend to be unstable. Therefore, the embodiments of the present application can design the parameters of the active damping transfer function for the most unfavorable operating conditions, such as the case where the RAP control bandwidth and L g are the largest, to ensure that the control strategy can work effectively under a wider range of operating conditions. Further, in the embodiments of the present application, when the RAP mode is located at about -110 (corresponding to 17 Hz) and L g is 0.5 p.u., and the corresponding short-circuit ratio is equal to 2, the LCL resonance can be effectively suppressed.

[0059] In addition, it should be noted that the embodiments of the present application can calculate the corresponding minimum reactive power modal pole from the maximum reactive power control bandwidth, calculate the corresponding maximum line inductance value from the minimum short-circuit ratio, and then calculate the system characteristic quantity by using the minimum reactive power modal pole and the maximum line inductance value.

[0060] In some embodiments, the embodiments of the present application can obtain the corresponding system parameters by acquiring the rated resonance frequency of the LCL filter in the single-loop grid-forming permanent magnet synchronous wind power generation system.

[0061] Optionally, in an embodiment of the present application, based on the system parameters that meet the first preset condition, the system characteristic quantity that meets the second preset condition, and the stability index that meets the third preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system, calculate the proportional coefficient and the time constant in the active damping transfer function, including: calculating the proportional coefficient in the active damping transfer function based on the system characteristic quantity and the stability index; calculating the time constant based on the system parameters.

[0062] In some embodiments, the proportional coefficient in the active damping transfer function of the embodiments of the present application can be calculated from system characteristic quantities such as the minimum reactive power mode pole and the maximum line inductance value, and stability indicators. The calculation of the time constant only requires calculation through system parameters.

[0063] Exemplarily, the proportional coefficient k of the embodiments of the present application d is calculated as follows: Among them, the embodiments of the present application can be based on the small-signal analysis method. When the time constant T d = 0, the root locus analysis method is used to obtain the optimal proportional coefficient k d , and ensure that this value can meet the requirements of the stability indicators. Among them, in the embodiments of the present application, k d = 3.3×10 -6 . As Figure 5 shown, the positions of the system eigenvalues conform to the defined specifications and stability margins, and ensure that it is applicable to the most adverse operating conditions.

[0064] Furthermore, in the embodiments of the present application, the calculation content of the time constant T d can be: To avoid the problem of noise amplification caused by pure derivative calculation in actual operating conditions, the embodiments of the present application introduce the time constant T d , and set it as T d = 8×10 -5 , to ensure that the break frequency is 2 kHz, which is twice the designed LCL resonance frequency.

[0065] In step S103, the active damping transfer function is quantified according to the proportional coefficient and the time constant to obtain an active damping compensation transfer function applicable to the single-loop grid-connected permanent magnet synchronous wind power generation system, which is used to calculate the active damping in the single-loop grid-connected permanent magnet synchronous wind power generation system.

[0066] From the above analysis, it can be seen that k d = 3.3×10 -6 , T d = 8×10 -5 . Furthermore, the embodiments of the present application quantify the corresponding active damping transfer function based on the obtained proportional coefficient and time constant, and then obtain the active damping compensation transfer function to calculate the active damping in the single-loop grid-connected permanent magnet synchronous wind power generation system. Among them, the expression of the active damping compensation transfer function can be but is not limited to:

[0067]

[0068] Next, the working principle of the method for calculating the active damping in the wind power generation system proposed by the embodiments of the present application will be introduced in combination with a specific embodiment.

[0069] Embodiment 1:

[0070] The embodiments of this application are verified through an improved IEEE (Institute of Electrical and Electronics Engineers) test system to determine the effectiveness of the method proposed in the embodiments of this application. The results show that the embodiments of this application can effectively suppress the system resonance mode, improve the dynamic response performance of the system, and have good robustness and engineering application value.

[0071] Among them, in the embodiments of this application, Figure 6 The structure diagram of the IEEE nine-bus system for simulation is shown. A permanent magnet synchronous wind power generation system with a single-loop network-forming control is connected to bus 3, and the system parameters are set as shown in Table 1. Among them, Table 1 is the system parameter setting table provided according to an embodiment of this application.

[0072] Table 1

[0073]

[0074]

[0075] Furthermore, the embodiments of this application can be based on the parameters in Table 1, and the simulation results of the DC bus voltage v dc , active power p, and reactive power q are as Figure 7 shown. Initially, the system runs stably; at t = 5 s, k q is increased from 4 to 11, so that the bandwidth corresponding to the RAP mode is increased from 6 Hz to 17 Hz. It can be observed that high-frequency oscillations occur in all three control loops of the system and gradually tend to be unstable. Subsequently, the proposed active damping control method is activated at t = 13, and these oscillations are quickly suppressed. Figure 7 It is proved that the instability of the system mainly stems from the LCL resonance, rather than the low-frequency interaction. At the same time, the RAP control will affect the resonance stability, and a larger RAP control bandwidth will exacerbate the instability of the system.

[0076] In another set of tests, the grid-side inductor L g is increased to 0.5 p.u., and its simulation results are as Figure 8 shown. To ensure the stable operation of the system, k q is reduced to 2 initially. It can be observed that when k q is restored to the original value of 4 at t = 5 s, the system cannot maintain stability and high-frequency oscillations occur. This confirms that a larger L g (i.e., a weaker power grid) will deteriorate the resonance stability of the single-loop network-forming inverter. In contrast, when the active damping control method proposed in the embodiments of this application is applied, the system oscillations are effectively suppressed. Figure 7 andFigure 8 All indicate that the embodiments of the present application can effectively suppress the high-frequency oscillation of the single-loop grid-forming permanent magnet synchronous wind power generation system caused by LCL resonance, maintain the system stability under different RAP bandwidths and grid strength change conditions, and have strong robustness.

[0077] According to the calculation method of active damping in the wind power generation system proposed by the embodiments of the present application, based on the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system, an active damping transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system can be constructed. Then, according to the system parameters satisfying the first preset condition, the system characteristic quantities satisfying the second preset condition, and the stability index satisfying the third preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system, the proportional coefficient and time constant in the active damping transfer function are calculated. Furthermore, the active damping transfer function is quantified to obtain an active damping compensation transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system, realizing the calculation of active damping in the single-loop grid-forming permanent magnet synchronous wind power generation system. By adding an active damping control strategy with filter capacitor voltage feedback in the single-loop grid-forming permanent magnet synchronous wind power generation system, the influence of the single-loop control system on LCL resonance is fully considered, effectively suppressing high-frequency resonance and improving system stability. Thus, in the related art, for the single-loop grid-forming system, due to the lack of consideration of the LCL filter resonance dynamics and non-minimum phase characteristics, and the influence of RAP control on the LCL resonance mode, the phenomenon of high-frequency resonance-dominated instability is likely to occur. In addition, there are also problems such as the lack of theoretical support for the compatibility of certain parameter design criteria and control structures in the single-loop grid-forming system.

[0078] Secondly, a calculation device for active damping in the wind power generation system proposed by the embodiments of the present application is described with reference to the accompanying drawings.

[0079] Figure 9 It is a block diagram of a calculation device for active damping in the wind power generation system provided by the embodiments of the present application.

[0080] As Figure 9 shown, the calculation device 10 for active damping in the wind power generation system includes: a construction module 100, a calculation module 200, and a generation module 300.

[0081] Among them, the construction module 100 is used to construct an active damping transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system based on the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system.

[0082] A calculation module 200 is configured to calculate a proportional coefficient and a time constant in an active damping transfer function based on system parameters that meet a first preset condition, system characteristic quantities that meet a second preset condition, and a stability index that meets a third preset condition in a single-loop grid-forming permanent magnet synchronous wind power generation system.

[0083] A generation module 300 is configured to quantify the active damping transfer function according to the proportional coefficient and the time constant to obtain an active damping compensation transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system, and is used to calculate the active damping in the single-loop grid-forming permanent magnet synchronous wind power generation system.

[0084] Optionally, in an embodiment of the present application, a construction module 100 includes: a first determination unit and a construction unit.

[0085] Wherein, the first determination unit is configured to determine a voltage signal acting on a filter capacitor in the single-loop grid-forming permanent magnet synchronous wind power generation system based on a control strategy of the single-loop grid-forming inverter and a control strategy of the permanent magnet synchronous wind power generation system.

[0086] The construction unit is configured to construct an active damping transfer function according to the voltage signal.

[0087] Optionally, in an embodiment of the present application, the calculation module 200 includes: an acquisition unit, a second determination unit, a first calculation unit, and a generation unit.

[0088] Wherein, the acquisition unit is configured to acquire a maximum reactive power control bandwidth and a minimum short-circuit ratio in the single-loop grid-forming permanent magnet synchronous wind power generation system.

[0089] The second determination unit is configured to determine operating condition information based on the maximum reactive power control bandwidth and the minimum short-circuit ratio.

[0090] The first calculation unit is configured to calculate system characteristic quantities in the active damping transfer function based on the operating condition information.

[0091] The generation unit is configured to acquire a rated resonance frequency of an LCL filter in the single-loop grid-forming permanent magnet synchronous wind power generation system, and obtain system parameters according to the rated resonance frequency of the LCL filter.

[0092] Optionally, in an embodiment of the present application, the calculation module 200 includes: a second calculation unit and a third calculation unit.

[0093] Wherein, the second calculation unit is configured to calculate a proportional coefficient in the active damping transfer function based on the system characteristic quantities and the stability index.

[0094] The third calculation unit is configured to calculate a time constant based on the system parameters.

[0095] Optionally, in an embodiment of the present application, the expression of the active damping transfer function may but is not limited to:

[0096]

[0097] where s is a complex number, and k d is the proportional coefficient in the active damping, and T d is the time constant.

[0098] It should be noted that the foregoing explanation of the embodiments of the calculation method of the active damping in the wind power generation system also applies to the calculation device of the active damping in the wind power generation system of this embodiment, and will not be elaborated here.

[0099] The calculation device of the active damping in the wind power generation system proposed according to the embodiments of the present application can construct an active damping transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system based on the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system. Furthermore, according to the system parameters satisfying the first preset condition, the system characteristic quantities satisfying the second preset condition, and the stability index satisfying the third preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system, the proportional coefficient and the time constant in the active damping transfer function are calculated, and then the active damping transfer function is quantified to obtain an active damping compensation transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system, realizing the calculation of the active damping in the single-loop grid-forming permanent magnet synchronous wind power generation system. By adding an active damping control strategy with filter capacitor voltage feedback in the single-loop grid-forming permanent magnet synchronous wind power generation system, the influence of the single-loop control system on the LCL resonance is fully considered, the high-frequency resonance is effectively suppressed, and the system stability is improved. Thus, in the related art, for a single-loop grid-forming system, due to the lack of consideration of the LCL filter resonance dynamics and non-minimum phase characteristics, and the influence of the RAP control on the LCL resonance mode, the phenomenon of instability dominated by high-frequency resonance is likely to occur. In addition, there are also problems such as the lack of theoretical support for the compatibility between certain parameter design criteria and the control structure in the single-loop grid-forming system.

[0100] Figure 10 It is a schematic structural diagram of an electronic device provided according to an embodiment of the present application. The electronic device may include:

[0101] A memory 1001, a processor 1002, and a computer program stored on the memory 1001 and executable on the processor 1002.

[0102] When the processor 1002 executes the program, it implements the calculation method of the active damping in the wind power generation system provided in the above embodiment.

[0103] Furthermore, the electronic device further includes:

[0104] A communication interface 1003 for communication between the memory 1001 and the processor 1002.

[0105] A memory 1001 for storing a computer program that can run on the processor 1002.

[0106] The memory 1001 may include high-speed RAM memory and may also include non-volatile memory, such as at least one disk memory.

[0107] If the memory 1001, the processor 1002, and the communication interface 1003 are implemented independently, the communication interface 1003, the memory 1001, and the processor 1002 can be interconnected via a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, Figure 10 only a thick line is used to represent it in the figure, but it does not mean that there is only one bus or one type of bus.

[0108] Optionally, in a specific implementation, if the memory 1001, the processor 1002, and the communication interface 1003 are integrated on a single chip, the memory 1001, the processor 1002, and the communication interface 1003 can communicate with each other through an internal interface.

[0109] The processor 1002 may be a Central Processing Unit (CPU), or an Application Specific Integrated Circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0110] The embodiments of the present application also provide a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the calculation method of active damping in the wind power generation system as described above is implemented.

[0111] The embodiments of the present application also provide a computer program product, including a computer program, and when the program is executed, the calculation method of active damping in the wind power generation system as described above is implemented.

[0112] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0113] In addition, the terms "first" and "second" are used only for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of this application, the meaning of "N" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0114] Any process or method description shown in the flowchart or described in other ways herein can be understood as representing a module, segment, or part of code including one or N executable instructions for implementing a customized logic function or process, and the scope of the preferred embodiments of this application includes additional implementations, where the functions can be executed in a manner that is not in the order shown or discussed, including in a substantially simultaneous manner according to the functions involved or in the reverse order, which should be understood by those skilled in the art to which the embodiments of this application belong.

[0115] Logic and / or steps represented in a flowchart or otherwise described herein, for example, can be considered as a definitional sequence list of executable instructions for implementing logical functions, which can be embodied specifically in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device. As used in this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium include the following: an electrical connection part (electronic device) having one or N wirings, a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable medium on which the program can be printed, because the program can be obtained electronically by optically scanning the paper or other medium, followed by editing, deciphering, or otherwise processing it as appropriate, and then storing it in a computer memory.

[0116] It should be understood that various parts of the present application can be implemented by hardware, software, firmware, or a combination thereof. In the above-described embodiments, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, any one or a combination of the following techniques known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application specific integrated circuits having suitable combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

[0117] Those of ordinary skill in the art of this technology can understand that all or part of the steps carried by the method of the above-described embodiments can be completed by a program instructing relevant hardware, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0118] In addition, each functional unit in various embodiments of the present application may be integrated into one processing module, or each unit may exist physically alone, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0119] The above-mentioned storage medium may be a read-only memory, a magnetic disk, an optical disc, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A calculation method for active damping in a wind power generation system, characterized in that, Including the following steps: Based on the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system, construct an active damping transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system; Based on the system parameters that meet the first preset condition, the system characteristic quantities that meet the second preset condition, and the stability index that meets the third preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system, calculate the proportional coefficient and time constant in the active damping transfer function; Quantify the active damping transfer function according to the proportional coefficient and the time constant to obtain an active damping compensation transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system, which is used to calculate the active damping in the single-loop grid-forming permanent magnet synchronous wind power generation system.

2. The method according to claim 1, characterized in that The constructing an active damping transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system based on the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system includes: Based on the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system, determine the voltage signal acting on the filter capacitor in the single-loop grid-forming permanent magnet synchronous wind power generation system; Construct the active damping transfer function according to the voltage signal.

3. The method according to claim 1, wherein The system parameters that meet the first preset condition and the system characteristic quantities that meet the second preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system include: Obtain the maximum reactive power control bandwidth and the minimum short-circuit ratio in the single-loop grid-forming permanent magnet synchronous wind power generation system; Based on the maximum reactive power control bandwidth and the minimum short-circuit ratio, determine the operating condition information; Based on the operating condition information, calculate the system characteristic quantities in the active damping transfer function; Obtain the rated resonant frequency of the LCL filter in the single-loop grid-forming permanent magnet synchronous wind power generation system, and obtain the system parameters according to the rated resonant frequency of the LCL filter.

4. The method according to claim 1, characterized in that, The calculating the proportional coefficient and time constant in the active damping transfer function based on the system parameters that meet the first preset condition, the system characteristic quantities that meet the second preset condition, and the stability index that meets the third preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system includes: Based on the system characteristic quantities and the stability index, calculate the proportional coefficient in the active damping transfer function; Based on the system parameters, calculate the time constant.

5. The method according to claim 1, wherein The expression of the active damping transfer function is: where s is a complex number, and k d is the proportionality coefficient in the active damping, and T d is the time constant.

6. A calculation device for active damping in a wind power generation system, characterized in that, Including: A construction module, configured to construct an active damping transfer function applicable to the single-loop grid-forming permanent magnet synchronous wind power generation system based on the control strategy of the single-loop grid-forming inverter and the control strategy of the permanent magnet synchronous wind power generation system; A calculation module, configured to calculate the proportional coefficient and time constant in the active damping transfer function based on the system parameters that meet the first preset condition, the system characteristic quantities that meet the second preset condition, and the stability index that meets the third preset condition in the single-loop grid-forming permanent magnet synchronous wind power generation system; A generation module, configured to quantify the active damping transfer function according to the proportionality coefficient and the time constant quantity, so as to obtain an active damping compensation transfer function applicable to a single-loop grid-forming permanent magnet synchronous wind power generation system, and used for calculating the active damping in the single-loop grid-forming permanent magnet synchronous wind power generation system.

7. The device according to claim 6, characterized in that, The construction module includes: A first determination unit, configured to determine a voltage signal acting on a filter capacitor in the single-loop grid-forming permanent magnet synchronous wind power generation system based on a control strategy of the single-loop grid-forming inverter and a control strategy of the permanent magnet synchronous wind power generation system; A construction unit, configured to construct the active damping transfer function according to the voltage signal.

8. An electronic device, characterized in that, It includes: A memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor executes the program to implement the method for calculating active damping in the wind power generation system according to any one of claims 1-5.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to be used for implementing the method for calculating active damping in the wind power generation system according to any one of claims 1-5.

10. A computer program product, characterized in that, It includes a computer program, which when executed, is used for implementing the method for calculating active damping in the wind power generation system according to any one of claims 1-5.

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