Direct-drive fan admittance self-test method and device, electronic equipment and medium

Abstract

The invention discloses a direct-drive fan admittance self-test method and device, electronic equipment and a medium, and relates to the technical field of wind power generation, and the method comprises the steps: generating and injecting a disturbance signal based on a direct-drive fan; performing data acquisition by using the disturbance signal to obtain a time domain signal of the direct-driven fan; on the basis of the time domain signal of the direct-driven fan, frequency domain data of the direct-driven fan are obtained through fast Fourier transform; and performing measurement verification according to the frequency domain data of the direct-driven fan to obtain a direct-driven fan admittance self-test result. Through the innovative disturbance injection and frequency domain identification technology, under the condition of not depending on internal control parameters, high-precision measurement of the admittance characteristics of the black-box direct-drive fan is achieved, and the industrial problems that a traditional method depends on the internal parameters, frequency bands are limited, and engineering implementation is complex are solved. The method has the advantages of high precision, wide frequency band, online measurement and the like, so that the method has a wide application prospect in the field of new energy grid-connected stability analysis.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of wind power generation, in particular to a direct-drive wind turbine admittance self-measuring method and device, electronic equipment and medium. BACKGROUND

[0002] Under the background of high proportion of wind power access to weak AC system, direct-drive wind farm has become the mainstream technical solution of wind power grid connection due to the advantages of no need for gearbox, high power generation efficiency, low maintenance cost and the like. However, with the continuous increase of wind power penetration, the stability problem of direct-drive wind turbine grid-connected system is increasingly prominent. Among them, the wide frequency oscillation phenomenon caused by converter control shows a multi-occurrence trend, which seriously threatens the safe operation of power grid.

[0003] As the core parameter for analyzing such dynamic interaction problems, the frequency domain characteristics of the admittance matrix directly reflect the dynamic response of the system at different frequencies, and its accuracy is crucial for the stability evaluation of the grid-connected system. However, the current direct-drive wind turbine admittance modeling and measurement still faces key challenges:

[0004] (1) Difficulty in admittance modeling caused by black-box wind turbine system: Modern direct-drive wind turbine converters generally adopt highly integrated modular design, and their control strategies (such as the dynamic response characteristics of phase-locked loop (PLL), PI parameters of current inner loop regulator, compensation algorithm of DC voltage outer loop, etc.) are strictly kept secret by manufacturers as core secrets, and end users cannot obtain internal parameters and accurate mathematical models, which makes the traditional admittance analytical modeling method based on "white box assumption" completely invalid;

[0005] (2) Limitations of traditional measurement methods: Existing measurement techniques either rely on internal control parameters, or have narrow frequency band coverage (difficult to cover the key frequency band of 1Hz-1kHz wide frequency oscillation), or are complex in engineering implementation, which cannot meet the demand of "high precision, wide frequency band, online measurement" of direct-drive wind turbine admittance parameters in actual power grid.

[0006] Therefore, there is an urgent need for a direct-drive wind turbine admittance self-measuring method, device, electronic equipment and medium to solve the problems in the prior art. SUMMARY

[0007] The present application aims to provide a direct-drive wind turbine admittance self-measuring method, device, electronic equipment and medium to solve the problems of black-box direct-drive wind turbine admittance modeling difficulty, narrow frequency band of traditional methods, and dependence on internal parameters, and to realize high-precision, wide-frequency-band, online self-measurement of direct-drive wind turbine admittance characteristics, and to provide reliable parameter support for stability evaluation of grid-connected system.

[0008] In order to achieve the above-mentioned purpose, the present application provides a direct-drive wind turbine admittance self-measuring method, which comprises the following steps:

[0009] S1, based on a direct-drive wind turbine, generating and injecting a disturbance signal;

[0010] S2, data acquisition is performed by using the disturbance signal to obtain the time domain signal of the direct-drive wind turbine;

[0011] S3, frequency domain data of the direct-drive wind turbine are obtained by using fast Fourier transform based on the time domain signal of the direct-drive wind turbine;

[0012] S4, measurement verification is performed according to the frequency domain data of the direct-drive wind turbine to obtain the admittance self-test result of the direct-drive wind turbine.

[0013] Optionally, the direct-drive wind turbine comprises a grid-side converter, a machine-side converter and a motor system.

[0014] The grid-side converter adopts outer ring DC voltage control and inner ring current control, and the machine-side converter adopts outer ring power control and inner ring current control.

[0015] Optionally, S1, based on the direct-drive wind turbine, a disturbance signal is generated and injected, comprising:

[0016] Based on the direct-drive wind turbine, a grid-side converter input port signal and a grid-side converter output port signal of the direct-drive wind turbine are obtained;

[0017] According to the grid-side converter input port signal of the direct-drive wind turbine, a positive and negative sequence voltage disturbance component, a positive and negative sequence current disturbance component and a DC voltage disturbance component are generated and injected;

[0018] According to the grid-side converter output port signal of the direct-drive wind turbine, a positive and negative sequence modulation coefficient disturbance component is generated and injected;

[0019] The positive and negative sequence voltage disturbance component, the positive and negative sequence current disturbance component, the DC voltage disturbance component and the positive and negative sequence modulation coefficient disturbance component are obtained as the disturbance signal.

[0020] Optionally, S2, data acquisition is performed by using the disturbance signal to obtain the time domain signal of the direct-drive wind turbine, comprising:

[0021] Based on the disturbance signal, small signal components of a grid-side converter input signal, a grid-side converter output signal, a grid-side converter output voltage, a point of common coupling voltage and a point of common coupling current are collected;

[0022] According to the small signal components of the grid-side converter input signal, the grid-side converter output signal, the grid-side converter output voltage, the point of common coupling voltage and the point of common coupling current, small signal components of a DC side voltage and a DC side current are synchronously collected;

[0023] The small signal components of the grid-side converter input signal, the grid-side converter output signal, the grid-side converter output voltage, the point-of-common coupling voltage, the point-of-common coupling current, the DC-side voltage and the DC-side current are obtained as time domain signals of the direct-drive wind turbine.

[0024] Optionally, S3, based on the time domain signals of the direct-drive wind turbine, frequency domain data of the direct-drive wind turbine is obtained by using fast Fourier transform, including:

[0025] Based on the small signal components of the grid-side converter input signal and the grid-side converter output signal, positive and negative sequence components of a small signal transfer function of the grid-side converter are obtained by using fast Fourier transform;

[0026] Based on the small signal components of the grid-side converter output signal, the grid-side converter output voltage, the point-of-common coupling voltage and the point-of-common coupling current, positive and negative sequence components of a small signal model of grid inductance and grid-side converter inductance are obtained by using fast Fourier transform;

[0027] Based on the small signal components of the DC-side voltage and the DC-side current, small signal components of a small signal model of the machine-side converter and the motor system are obtained by using fast Fourier transform;

[0028] The positive and negative sequence components of the small signal transfer function of the grid-side converter, the positive and negative sequence components of the small signal model of the grid inductance and the grid-side converter inductance and the small signal components of the small signal model of the machine-side converter and the motor system are obtained as frequency domain data of the direct-drive wind turbine.

[0029] Optionally, S4, according to the frequency domain data of the direct-drive wind turbine, a direct-drive wind turbine admittance self-test result is obtained by measurement verification, including:

[0030] Based on the frequency domain data of the direct-drive wind turbine and in combination with a small signal model of the grid-side converter, a small signal transfer function of the grid-side converter is obtained;

[0031] Based on the frequency domain data of the direct-drive wind turbine and in combination with dynamic characteristics of the grid inductance and the grid-side converter inductance, a small signal model of the grid inductance and the grid-side converter inductance is obtained;

[0032] According to the frequency domain data of the direct-drive wind turbine, a small signal model of the machine-side converter and the motor system is obtained;

[0033] By using the small signal transfer function of the grid-side converter, the small signal model of the grid inductance and the grid-side converter inductance and the small signal model of the machine-side converter and the motor system, a small signal model of the direct-drive wind turbine is obtained;

[0034] According to the small signal model of the direct-drive wind turbine and a small signal theoretical model of the direct-drive wind turbine, a direct-drive wind turbine admittance self-test result is obtained by test verification.

[0035] Optionally, the small signal theory model of the direct drive fan is:

[0036]

[0037] Wherein, I gsps is the positive sequence current component at the outlet of the grid-side converter, I gsns is the negative sequence current component at the outlet of the grid-side converter, s is the Laplace operator, j is the imaginary unit, ω1 is the fundamental frequency, Y pp is the admittance of the positive sequence current to the positive sequence voltage, Y pn is the admittance of the positive sequence current to the negative sequence voltage, Y np is the admittance of the negative sequence current to the positive sequence voltage, Y nn is the admittance of the negative sequence current to the negative sequence voltage, V gsps is the positive sequence voltage component at the grid-connection point of the fan, V gsns is the negative sequence voltage component at the grid-connection point of the fan.

[0038] In a second aspect, to achieve the above object, the present application provides a direct drive fan admittance self-test device, comprising: a disturbance input module, a data acquisition module, a signal processing module and a measurement verification module.

[0039] The disturbance input module is configured to generate and inject a disturbance signal based on the direct drive fan.

[0040] The data acquisition module is configured to acquire time domain signals of the direct drive fan by data acquisition using the disturbance signal.

[0041] The signal processing module is configured to acquire frequency domain data of the direct drive fan by fast Fourier transform based on the time domain signals of the direct drive fan.

[0042] The measurement verification module is configured to acquire the direct drive fan admittance self-test result by measurement verification based on the frequency domain data of the direct drive fan.

[0043] In a third aspect, an electronic device is provided, which includes one or more processors; and a storage device having one or more programs stored thereon, the one or more programs, when executed by the one or more processors, cause the one or more processors to implement the method described in any of the implementations of the first aspect.

[0044] In a fourth aspect, a computer-readable storage medium is provided, which has a computer program stored thereon, the computer program, when executed by one or more processors, implements the method described in any of the implementations of the first aspect.

[0045] Compared with the closest prior art, the present application has the beneficial effects that:

[0046] The present application realizes high-precision measurement of the admittance characteristics of a black-box direct-drive wind turbine by innovative disturbance injection and frequency domain identification technology without relying on internal control parameters, and solves the industry pain points of traditional methods relying on internal parameters, limited frequency band, and complex engineering implementation. The advantages of high precision, wide frequency band, and online measurement make it have broad application prospects in the field of new energy grid stability analysis, and provide strong technical support for the safe operation of future smart grids. The specific technical effects are as follows:

[0047] (1) Breakthrough of black-box system modeling limitation, realization of high-precision admittance identification. Traditional admittance modeling methods rely heavily on the internal control parameters of the converter, while the control strategy of modern direct-drive wind turbines is usually strictly confidential by the manufacturer, making it impossible for end users to obtain accurate mathematical models. The present application innovatively adopts a control signal injection disturbance strategy to realize precise measurement of the admittance characteristics of the black-box system without relying on internal parameters.

[0048] (2) Covering a wide frequency range, effectively capturing oscillation occurrence. The wide-frequency oscillation problem of direct-drive wind turbine grid-connected systems poses a serious threat to grid safety. Traditional modeling methods are difficult to accurately predict these oscillations due to the narrow frequency band and low precision. The self-measurement method of the present application optimizes the disturbance signal injection method by injecting disturbance into the modulated signal, which can effectively cover the key frequency band of 1Hz-1kHz. This feature enables grid operators to identify system risks and take targeted suppression measures to avoid large-scale oscillation accidents. BRIEF DESCRIPTION OF DRAWINGS

[0049] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the description of the specific embodiments or the prior art. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0050] Figure 1 The flowchart of a direct-drive wind turbine admittance self-measurement method according to an embodiment of the present application;

[0051] Figure 2 The topology structure diagram of a direct-drive wind turbine system according to an embodiment of the present application;

[0052] Figure 3 The control structure schematic diagram of a grid-side converter according to an embodiment of the present application;

[0053] Figure 4 The control structure schematic diagram of a machine-side converter according to an embodiment of the present application;

[0054] Figure 5 A structural schematic diagram of a direct drive fan admittance self-test device according to an embodiment of the present application;

[0055] Figure 6 A small signal model Y of a direct drive fan according to an embodiment of the present application pp A self-test verification diagram;

[0056] Figure 7 A small signal model Y of a direct drive fan according to an embodiment of the present application pn A self-test verification diagram;

[0057] Figure 8 A small signal model Y of a direct drive fan according to an embodiment of the present application np A self-test verification diagram;

[0058] Figure 9 A small signal model Y of a direct drive fan according to an embodiment of the present application nn A self-test verification diagram;

[0059] Figure 10 A structural schematic diagram of an electronic device according to an embodiment of the present application. DETAILED DESCRIPTION

[0060] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0061] The terms used in the embodiments of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application.

[0062] As shown in Figure 1 The embodiment of the present application provides a direct drive fan admittance self-test method, comprising:

[0063] S1, generating and injecting a disturbance signal based on a direct drive fan;

[0064] S2, collecting data using the disturbance signal to obtain time domain signals of the direct drive fan;

[0065] S3, obtaining frequency domain data of the direct drive fan using fast Fourier transform based on the time domain signals of the direct drive fan;

[0066] S4, measuring and verifying according to the frequency domain data of the direct drive fan to obtain a direct drive fan admittance self-test result.

[0067] In summary, steps S1 to S4 break through the traditional modeling idea, and realize accurate identification of the admittance characteristics of the black box system without relying on internal control parameters by designing a special disturbance injection method. This breakthrough technology provides an effective solution to the dilemma of breaking the admittance modeling of the black box fan system, and has important engineering value for ensuring the stable operation of the high-proportion new energy power grid.

[0068] As a possible implementation, in the above embodiment, the direct-drive fan includes a grid-side converter, a machine-side converter and a motor system;

[0069] The grid-side converter adopts outer ring DC voltage control and inner ring current control, and the machine-side converter adopts outer ring power control and inner ring current control.

[0070] As shown in Figure 2 The present application adopts a direct-drive fan topology, in which a wind wheel directly drives a generator to generate alternating current with a frequency and amplitude varying with wind speed. The machine-side converter adopts outer ring power control and inner ring current control, and uses a maximum power point tracking (MPPT) method to make the fan run at an optimal speed, so as to maximize the capture of wind energy and rectify the varying alternating current into direct current. The grid-side converter adopts outer ring DC voltage control and inner ring current control, and transmits the power delivered by the machine side to the grid and maintains the stability of the DC bus voltage. Figure 2 v wind is the input wind speed, P m is the mechanical power generated by the blade, ω m is the mechanical angular velocity of the blade, PMSG is a permanent magnet synchronous generator, i tsc is the machine-side alternating current, u tsc is the machine-side alternating voltage, i tsdc is the machine-side direct current, i gsdc is the grid-side direct current, C dc is a DC capacitor, u dc is a DC voltage, L gsc is a grid-side converter inductance, i gs is a grid-side alternating current, u gs is a grid-side alternating voltage, Z grid is a grid (Grid) inductance, θ s is a machine-side electrical angle, m tsck is a machine-side converter k (k=a, b, c) phase modulation coefficient, m gsck is a grid-side converter k phase modulation coefficient, PLL is a phase-locked loop, P ref is a machine-side active power reference value, P s is a machine-side active power, i ref is a current reference value, m dm is the d-axis modulation coefficient. q θ is the q-axis modulation coefficient. PLL For the phase-locked loop output electrical angle, u dcref This is the reference value for DC voltage.

[0071] First, the dynamic characteristics of the grid-side converter inductance and the grid inductance are analyzed, as shown below:

[0072] (1)

[0073] (2)

[0074] Among them, V gscps V is the positive sequence voltage at the grid-side converter output, s is the Laplace operator, j is the imaginary unit, ω1 is the fundamental angular frequency, and V gscns Z is the negative sequence voltage at the grid-side converter output. gsL I is the small-signal impedance matrix of the converter outlet inductance. gsps I represents the positive sequence current component at the grid-side converter outlet. gsns V represents the negative sequence current component at the grid-side converter outlet. gsps V represents the positive sequence voltage component at the wind turbine's grid connection point. gsns Negative sequence voltage component at the wind turbine grid connection point, Z grid This is the small-signal impedance matrix of the grid inductance.

[0075] The small-signal impedance matrix Z of the converter outlet inductor gsL The small-signal impedance matrix Z of the grid inductance grid The detailed expression is as follows:

[0076] (3)

[0077] (4)

[0078] Among them, Z gsLpp Z represents the positive-sequence impedance of the grid-side converter inductor in the complex frequency domain. gsLnn Z represents the negative sequence impedance of the grid-side converter inductor in the complex frequency domain. gridpp Z represents the impedance of the positive sequence current at the grid-side converter outlet to the positive sequence voltage at the grid connection point. gridnp Z represents the impedance of the positive-sequence current at the grid-side converter outlet to the negative-sequence voltage at the grid connection point. gridpn Z represents the impedance of the negative sequence current at the grid-side converter outlet to the positive sequence voltage at the grid connection point. gridnn This represents the impedance of the negative sequence current at the grid-side converter outlet to the negative sequence voltage at the grid connection point.

[0079] like Figure 3 As shown, this is the control structure of the grid-side converter, employing outer-loop DC voltage control and inner-loop current control. Wherein, udc_ref =u dcref The reference value is the DC voltage, PI is a proportional-integral controller, and i d_ref i is the reference value for the d-axis component of the machine-side AC voltage. q_ref i is the reference value for the q-axis component of the machine-side AC voltage. gd i represents the d-axis component of the grid-side AC current. gq For the q-axis component of the grid-side AC current, u qg This represents the d-axis component of the grid-side AC voltage.

[0080] In a black-box scenario, the input and output of the converter can be determined. Taking a grid-side converter as an example, the input signal of the converter is: v g i g v dc The converter's output signal is: m gsc Among them, v g i is the AC voltage input signal for the grid-side converter. g For the AC current input signal of the grid-side converter, v dc For the DC voltage input signal of the grid-side converter, m gsc The output signal represents the modulation coefficients of the grid-side converter. Therefore, the small-signal model of the grid-side converter can be represented as follows:

[0081] (5)

[0082] Among them, M ps M represents the positive sequence modulation of the small-signal component of the grid-side converter. ns For the negative sequence modulation small signal component of the grid-side converter, G gscs V is the small-signal transfer function of the grid-side converter. dcp This represents the small-signal component of the DC voltage. The small-signal transfer function G of the grid-side converter. gscs The expression is as follows:

[0083] (6)

[0084] Among them, G vpp For M ps To V gsps The transfer function, G vpn For M ps To V gsns The transfer function, G ipp For M ps To I gsps The transfer function, G dcp For M ps To V dcp The transfer function, G vnp For M ns To V gspsThe transfer function, G vnn For M ns To V gsns The transfer function, G inn For M ns To I gsns The transfer function, G dcn For M ns To V dcp The transfer function.

[0085] like Figure 4 As shown, this is the control structure of the machine-side converter, employing outer-loop power control and inner-loop current control. Wherein, i td i represents the d-axis component of the machine-side AC current. tq This represents the q-axis component of the machine-side AC current.

[0086] When calculating the admittance of a direct-drive wind turbine system, from the DC side perspective, the turbine-side converter and motor system are considered as a single-port DC admittance model, which can then be expressed using Y... tss express:

[0087] Y tss (s)=I tsdcp (s) / V dcp (s)(7)

[0088] Among them, Y tss For the small-signal model of the machine-side converter and motor system, I tsdcp This refers to the small-signal component of the DC current output from the machine-side converter.

[0089] As one possible implementation, in the above embodiments, step S1 may specifically include the following steps:

[0090] S1-1. Based on the direct-drive fan, obtain the input port signal and output port signal of the grid-side converter of the direct-drive fan;

[0091] S1-2. Based on the input port signal of the grid-side converter of the direct-drive wind turbine, generate and inject positive and negative sequence voltage disturbance components, positive and negative sequence current disturbance components and DC voltage disturbance components.

[0092] S1-3. Generate and inject positive and negative sequence modulation coefficient disturbance components based on the output port signal of the grid-side converter of the direct-drive wind turbine;

[0093] S1-4. Obtain the positive and negative sequence voltage disturbance components, the positive and negative sequence current disturbance components, the DC voltage disturbance components, and the positive and negative sequence modulation coefficient disturbance components as disturbance signals.

[0094] Specifically, the positive sequence voltage perturbation V gsps Injected into the grid-side converter input voltage V gIn the middle, the negative sequence voltage perturbation V gsns Injected into the grid-side converter input voltage V g In the middle, the positive sequence current disturbance I gsps Injected current i into the grid-side converter input g In the middle, the negative sequence current perturbation I gsns Injected current i into the grid-side converter input g In the middle, the DC voltage disturbance V dcp Injected DC voltage v into the grid-side converter input dc In the middle, the forward-sequence modulation coefficient perturbation M gsps Injected into the grid-side converter output modulation coefficient m gsc In the middle, the negative sequence modulation coefficient is perturbed M gsns Injected into the grid-side converter output modulation coefficient m gsc middle.

[0095] As one possible implementation, in the above embodiments, step S2 may specifically include the following steps:

[0096] S2-1. Based on the disturbance signal, collect the small signal components of the grid-side converter input signal, grid-side converter output signal, grid-side converter output voltage, grid connection point voltage, and grid connection point current;

[0097] S2-2. Based on the input signal of the grid-side converter, the output signal of the grid-side converter, the output voltage of the grid-side converter, the grid connection point voltage and the small signal components of the grid connection point current, the small signal components of the DC side voltage and the DC side current are synchronously acquired.

[0098] S2-3. Obtain the input signal of the grid-side converter, the output signal of the grid-side converter, the output voltage of the grid-side converter, the grid connection point voltage, the grid connection point current, and the small signal components of the DC side voltage and the DC side current as the time domain signal of the direct-drive wind turbine.

[0099] Specifically, for each type of disturbance signal in step S1, the small-signal component of the AC voltage input signal of the grid-side converter is acquired in real time. Small-signal component of AC current input signal of grid-side converter Small signal component of DC voltage input signal of grid-side converter Small-signal component of the input signal of the modulation coefficient of the grid-side converter Small signal component of grid-side converter output voltage Small signal component of grid connection point voltage and the small-signal component of the grid connection point current. Simultaneously acquire the small signal components V of the DC side voltage and current. dcp (s), I tsdcp(s). During the acquisition process, the acquired data (i.e., real-domain data) is stored in a data buffer to prevent data loss.

[0100] As one possible implementation, in the above embodiments, step S3 may specifically include the following steps:

[0101] S3-1. Based on the small-signal components of the input signal and output signal of the grid-side converter, the positive and negative order components of the small-signal transfer function of the grid-side converter are obtained by using fast Fourier transform.

[0102] S3-2. Based on the small-signal components of the grid-side converter output signal, the grid-side converter output voltage, the grid connection point voltage, and the grid connection point current, the positive and negative sequence components of the small-signal model of the grid inductance and the grid-side converter inductance are obtained by using Fast Fourier Transform.

[0103] S3-3. Based on the small-signal components of the DC-side voltage and the DC-side current, the small-signal components of the small-signal model of the machine-side converter and motor system are obtained by using fast Fourier transform.

[0104] S3-4. Obtain the positive and negative sequence components of the small-signal transfer function of the grid-side converter, the positive and negative sequence components of the small-signal model of the grid inductance and the grid-side converter inductance, and the small-signal components of the small-signal model of the machine-side converter and the motor system as the frequency domain data of the direct-drive wind turbine.

[0105] Specifically, based on the time-domain signal of the direct-drive fan obtained in step S2, the time-domain signal is first subjected to noise filtering (removing 50Hz power frequency interference), and then the filtered time-domain signal is converted into a frequency-domain signal using Fast Fourier Transform (FFT) to obtain the frequency-domain data of the direct-drive fan, including G. gscs The positive and negative order components M required by the matrix ps M ns V gsps V gsns I gsps I gsns V dcp The positive and negative sequence components V required for the small-signal model of grid inductance and grid-side converter inductance gsps V gsns I gsps I gsns V gscps V gscns and Y tss The required small signal component V dcp I tsdcp .

[0106] As one possible implementation, in the above embodiments, step S4 may specifically include the following steps:

[0107] Based on the frequency domain data of the direct-drive wind turbine and the small-signal model of the grid-side converter, the small-signal transfer function of the grid-side converter is obtained.

[0108] Based on the frequency domain data of the direct-drive wind turbine and the dynamic characteristics of the grid-side converter inductance and grid inductance, small-signal models of the grid inductance and grid-side converter inductance are obtained.

[0109] Based on the frequency domain data of the direct-drive fan, obtain the small-signal model of the machine-side converter and motor system;

[0110] The small-signal model of the direct-drive wind turbine is obtained by using the small-signal transfer function of the grid-side converter, the small-signal model of the grid inductance and the grid-side converter inductance, and the small-signal model of the machine-side converter and motor system.

[0111] The small-signal model and the small-signal theoretical model of the direct-drive fan were tested and verified to obtain the admittance self-test results of the direct-drive fan.

[0112] Specifically, based on the frequency domain data from step S3, the small-signal transfer function G of the grid-side converter controller is calculated by combining equations (5), (1), and (7). gscs Small-signal model Z of grid inductance and grid-side converter inductance gsL Z grid And the small-signal model Y of the machine-side converter and motor system tss This allows for the simultaneous solution of the small-signal model of the direct-drive fan system. The small-signal model is then compared and verified with the theoretical model, and the results are displayed on the interface, providing visualized measurement data.

[0113] The method proposed in this embodiment is used to measure the small-signal transfer function G of the grid-side converter. gscs Specifically, this includes steps A1 to A9:

[0114] Step A1: Perturb the positive sequence voltage V gsps Injected into the grid-side converter input voltage V g middle;

[0115] Step A2: Measure the small-signal component of the input signal to the grid-side converter. , , and the small-signal component of the grid-side converter output signal ,in, This refers to the small-signal component of the AC voltage input signal of the grid-side converter. This refers to the small-signal component of the AC current input signal of the grid-side converter. This refers to the small-signal component of the DC voltage input signal of the grid-side converter. The small-signal component of the modulation coefficient output signal of the grid-side converter;

[0116] Step A3: Extract the solution G using FFT. gscs The positive and negative order components required for the matrix: M ps M ns V gsps V gsns I gsps I gsns V dcp ;

[0117] Step A4: Store the extracted positive and negative sequence components of the grid-side converter input and output in the following vector:

[0118] (8)

[0119] in, The vector for storing the positive and negative sequence components of the input to the first group of grid-side converters. T is the vector for storing the positive and negative sequence components of the output of the first group of grid-side converters, where T is the matrix transpose symbol.

[0120] Step A5: Perturb the negative sequence voltage V gsns Injected into the grid-side converter input voltage V g Then, repeat steps A2 to A4, and store the extracted small signal components of the grid-side converter input and output in memory. and In, among them, To store the vector of positive and negative sequence components of the input to the second group of grid-side converters, A vector for storing the positive and negative sequence components of the output of the second group of grid-side converters;

[0121] Step A6: Perturb I with positive sequence current gsps Injected current i into the grid-side converter input g Then, repeat steps A2 to A4, and store the extracted small signal components of the grid-side converter input and output in memory. and In, among them, The vector for storing the positive and negative sequence components of the input to the third group of grid-side converters. A vector for storing the positive and negative sequence components of the output from the third group of grid-side converters;

[0122] Step A7: Perturb I with negative sequence current gsns Injected current i into the grid-side converter input gThen, repeat steps A2 to A4, and store the extracted small signal components of the grid-side converter input and output in memory. and In, among them, The vector for storing the positive and negative sequence components of the input to the fourth group of grid-side converters. The vector for storing the positive and negative sequence components of the output of the fourth group of grid-side converters;

[0123] Step A8: Disturb the DC voltage V dcp Injected DC voltage v into the grid-side converter input dc Then, repeat steps A2 to A4, and store the extracted small signal components of the grid-side converter input and output in memory. and In, among them, To store the vector of positive and negative sequence components of the input to the fifth group of grid-side converters, To store the vector of positive and negative sequence components of the output of the fifth group of grid-side converters;

[0124] Step A9, combined with equation (5) and the disturbance components stored from steps A4 to A8, allows us to calculate the small-signal transfer function G of the grid-side converter as follows. gscs :

[0125] (9)

[0126] After obtaining G gscs Next, it is necessary to measure the small-signal model of the power grid and the converter inductance. The measurement logic specifically includes steps B1 to B6:

[0127] Step B1: Perturb M of the forward-sequence modulation coefficient gsps Injected into the grid-side converter output modulation coefficient m gsc middle;

[0128] Step B2: Measure the small-signal component of the grid-side converter output signal. Small signal component of grid-side converter output voltage Small signal component of grid connection point voltage Small signal component of grid connection point current ;

[0129] Step B3: Extract the positive and negative sequence components required for solving the small-signal models of the grid inductance and grid-side converter inductance using FFT: V gsps V gsns I gsps I gsns V gscps V gscns ;

[0130] Step B4: Store the extracted positive and negative order components in the following vector:

[0131] (10)

[0132] in, To store the vector of positive and negative sequence components of the output voltage of the first group of grid-side converters, To store the vector of positive and negative sequence components of the first set of grid-connected point voltages, To store the vector of the positive and negative sequence components of the first set of grid-connected currents, U gscps U represents the positive sequence component of the grid-side converter output voltage. gscns U represents the negative sequence component of the grid-side converter output voltage. gsps U is the positive sequence component of the grid connection point voltage. gsns For the negative sequence component of the grid connection point voltage, I gsps I is the positive sequence component of the grid connection point current. gsns This refers to the negative sequence component of the grid connection point current.

[0133] Step B5: Perturb M of the negative sequence modulation coefficient gsns Injected into the grid-side converter output modulation coefficient m gsc Then, repeat steps B2 to B4, and store the extracted small signal components. , and ,in, To store the vector of positive and negative sequence components of the output voltage of the second grid-side converter, To store the vector of positive and negative sequence components of the second set of grid-connected point voltages, This is a vector for storing the positive and negative sequence components of the second set of grid-connected currents;

[0134] Step B6, combined with equation (1) and the disturbance components stored from steps B4 to B5, allows for the calculation of the small-signal model of the grid and grid-side converter inductance as follows:

[0135] (11)

[0136] As shown above, the small-signal transfer function of the grid-side converter and the small-signal models of the grid and grid-side converter inductances are calculated, and the small-signal model of the grid-side converter can be obtained by combining them.

[0137] When measuring the small-signal model of the power grid and the grid-side converter inductance, the small-signal model Y of the machine-side converter and motor system can also be measured simultaneously. tss The measurement steps specifically include steps C1 to C4:

[0138] Step C1: Perturb M of the forward-sequence modulation coefficient gsps Injected into the grid-side converter output modulation coefficient mgsc middle;

[0139] Step C2: Measure the small-signal component V of the DC side voltage and current of the machine-side converter. dcp (s), I tsdcp (s), where V dcp (s) represents the small-signal component of the DC-side voltage of the machine-side converter, I tsdcp (s) represents the small-signal component of the DC-side current of the machine-side converter;

[0140] Step C3: Extract the solution Y using FFT. tss Required small signal component: V dcp I tsdcp ;

[0141] Step C4, combined with equation (7) and the disturbance component extracted from step C3, allows us to calculate the small-signal model Y of the machine-side converter and motor system. tss .

[0142] The small-signal transfer function G of the grid-side converter controller is obtained through the above steps. gscs Small-signal model Z of the grid and grid-side converter inductance gsL Z grid And the small-signal model Y of the machine-side converter and wind turbine system tss The small-signal model of the direct-drive fan system can be obtained by solving the simultaneous equations.

[0143] Furthermore, the small-signal theoretical model of the direct-drive fan system is shown below:

[0144] (12)

[0145] Among them, Y pp Y is the admittance of positive sequence current with respect to positive sequence voltage. pn Y is the admittance of the positive-sequence current with respect to the negative-sequence voltage. np Y is the admittance of negative sequence current with respect to positive sequence voltage. nn This is the admittance of the negative sequence current to the negative sequence voltage.

[0146] Further reference Figure 5 As an implementation of the methods shown in the above figures, this disclosure provides an embodiment of a direct-drive wind turbine admittance self-testing device, which is similar to... Figure 1 Corresponding to the method embodiments shown, this device can be specifically applied to various electronic devices.

[0147] like Figure 5 As shown, a direct-drive wind turbine admittance self-testing device according to this embodiment includes: a disturbance input module, a data acquisition module, a signal processing module, and a measurement verification module;

[0148] The disturbance input module is used to generate and inject disturbance signals based on the direct-drive fan, and also provides frequency input excitation for the measurement and verification module.

[0149] The disturbance input module is responsible for injecting disturbance signals as needed and providing frequency input excitation to the measurement verification module. It is directly connected to the direct-drive fan control system. This module allows control over the frequency and amplitude of the disturbance signal to achieve accurate measurements under different operating conditions and frequency ranges.

[0150] The data acquisition module is used to acquire data using the disturbance signal to obtain the time domain signal of the direct-drive fan;

[0151] The data acquisition module collects voltage, current, and modulation signals at various locations in real time after an applied disturbance to capture the response at different points in the wind turbine system and transmits the data to the signal processing module. This module ensures high-precision, high-speed signal sampling, providing accurate data for subsequent signal processing. The module includes a data buffer to store data during acquisition, ensuring signal continuity and preventing data loss.

[0152] The signal processing module is used to obtain the frequency domain data of the direct-drive fan by using a fast Fourier transform based on the time domain signal of the direct-drive fan.

[0153] The signal processing module receives signals from the data acquisition module and uses FFT to process the voltage and current signals transmitted by the data acquisition module. This primarily involves converting the time-domain signals into frequency-domain signals to obtain the amplitude and phase information of different signals at different frequencies, providing fundamental data for the impedance self-test calculation of the direct-drive wind turbine. The processed frequency-domain data is then transmitted to the measurement and verification module for subsequent calculations and verification.

[0154] The measurement and verification module is used to perform measurement and verification based on the frequency domain data of the direct-drive fan to obtain the self-test results of the admittance of the direct-drive fan.

[0155] The measurement verification module receives the frequency domain signal transmitted by the signal processing module. Using the processed frequency domain signal, it calculates small-signal models with different transfer functions and simultaneously solves the overall small-signal model of the direct-drive wind turbine. A frequency input excitation is provided through the disturbance input module, and the results are compared and verified with the analytical model. The results are displayed on the interface, providing visualized measurement data. The measurement verification module also has data storage capabilities, supporting long-term storage of measurement results for easy subsequent analysis and retrieval.

[0156] In summary, the disturbance input module, data acquisition module, signal processing module, and measurement verification module of the direct-drive wind turbine admittance self-testing device work together to form a complete measurement chain, from input signal generation to data acquisition, signal processing, and admittance self-testing and verification. This device not only achieves accurate self-testing of the direct-drive wind turbine admittance but also ensures system stability and safety during the self-testing process.

[0157] In this embodiment, the specific processing of a direct-drive wind turbine admittance self-testing device and its resulting technical effects can be referred to separately. Figure 3 The relevant descriptions of steps S1, S2, S3 and S4 in the corresponding embodiments will not be repeated here.

[0158] According to the content described in this invention, in accordance with Figure 1 The direct-drive fan system topology shown was used to build a corresponding simulation model in MATLAB / Simulink to verify the effectiveness and feasibility of the proposed direct-drive fan admittance self-test method. The parameters of the direct-drive fan system are shown in Table 1.

[0159] Table 1

[0160] Name Symbol Value Rated power P N ]]> 2 MW Rated voltage v a ]]> 690V Rated DC voltage v dc ]]> 500 kV Filter inductance L 0.02984 mH DC capacitance C 30 mF PLL parameters k pllp , k plli ]]> 1000，20000 DC voltage loop parameters k dcp , k dci ]]> 3，30 Grid-side current loop parameters k gscp , k gsci ]] 5，50 Power loop parameters k pp , k pi ]] 0.1，50 Machine-side current loop parameters k tscp , k tsci ]]> 1，50

[0161] Experiments verified the results of the small-signal model of the direct-drive fan obtained by simultaneous solution. The experimental results are as follows: Figure 6 - Figure 9 As shown, solid lines represent theoretical results, and dots represent self-test results. Figure 6 - Figure 9 Representing Y respectively pp Y pn Y np With Y nn A comparison of the self-test results and theoretical results in terms of amplitude and phase. As shown in the figure, the amplitude and phase curves of the four components basically overlap within a wide frequency range of 1Hz-1kHz. This demonstrates that the self-test method for the admittance of direct-drive fans proposed in this invention is effective and feasible.

[0162] It should be noted that the implementation details and technical effects of each module and unit in the device provided in the embodiments of this disclosure can be referred to the description of other embodiments in this disclosure, and will not be repeated here.

[0163] The following is for reference. Figure 10 It shows a schematic diagram of the structure of a computer system 500 suitable for implementing the electronic device of the present disclosure. Figure 10 The computer system 500 shown is merely an example and should not be construed as limiting the functionality and scope of the embodiments of this disclosure.

[0164] like Figure 10As shown, the computer system 500 may include a processing device 501 (e.g., a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM 502) or a program loaded from a storage device 508 into a random access memory (RAM 503). The RAM 503 also stores various programs and data required for the operation of the computer system 500. The processing device 501, ROM 502, and RAM 503 are interconnected via a bus 504. An input / output interface (I / O interface 505) is also connected to the bus 504.

[0165] Typically, the following devices can be connected to I / O interface 505: input devices 506 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, etc.; output devices 507 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 508 including, for example, magnetic tapes, hard disks, etc.; and communication devices 509. Communication device 509 allows computer system 500 to communicate wirelessly or wiredly with other devices to exchange data. Although Figure 10 A computer system 500 with various electronic devices is shown; however, it should be understood that it is not required to implement or possess all of the devices shown. More or fewer devices may be implemented or possessed alternatively.

[0166] In particular, according to embodiments of this disclosure, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this disclosure include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device 509, or installed from a storage device 508, or installed from a ROM 502. When the computer program is executed by the processing device 501, it performs the functions defined in the methods of embodiments of this disclosure.

[0167] It should be noted that the computer-readable medium described in this disclosure can be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this disclosure, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this disclosure, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium can be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wires, optical fibers, RF (radio frequency), etc., or any suitable combination thereof.

[0168] The aforementioned computer-readable medium may be included in the aforementioned electronic device; or it may exist independently and not assembled into the electronic device.

[0169] The aforementioned computer-readable medium carries one or more programs, which, when executed by the electronic device, cause the electronic device to perform the following functions: Figure 1 The illustrated embodiments and their alternative implementations demonstrate a method for self-testing the admittance of a direct-drive wind turbine.

[0170] Computer program code for performing the operations of this disclosure can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0171] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0172] The units or modules described in the embodiments of this disclosure can be implemented in software or hardware. The names of the units or modules do not necessarily limit the unit itself; for example, an acquisition module can also be described as "acquiring preset prompts, including modality fusion prompts, attention mechanism prompts, and / or time-related prompts."

[0173] The above description is merely a preferred embodiment of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features disclosed in this disclosure that have similar functions.

Claims

1. A direct drive fan admittance self-test method, characterized by, The method comprises the following steps: S1, generating and injecting a disturbance signal based on a direct-drive wind turbine; S2, collecting data by using the disturbance signal to obtain time-domain signals of the direct-drive wind turbine; S3, obtaining frequency-domain data of the direct-drive wind turbine by using fast Fourier transform based on the time-domain signals of the direct-drive wind turbine; S4, performing measurement verification according to the frequency-domain data of the direct-drive wind turbine to obtain a direct-drive wind turbine admittance self-test result.

2. A direct drive blower admittance self-test method according to claim 1, wherein, The direct-drive wind turbine comprises a grid-side converter, a machine-side converter and a motor system; The grid-side converter adopts outer-loop DC voltage control and inner-loop current control, and the machine-side converter adopts outer-loop power control and inner-loop current control.

3. A direct drive blower admittance self-test method according to claim 2, wherein, S1, generating and injecting a disturbance signal based on a direct-drive wind turbine, comprising: Based on the direct-drive wind turbine, obtaining grid-side converter input port signals and grid-side converter output port signals of the direct-drive wind turbine; According to the grid-side converter input port signals of the direct-drive wind turbine, generating and injecting positive and negative sequence voltage disturbance components, positive and negative sequence current disturbance components and DC voltage disturbance components; According to the grid-side converter output port signals of the direct-drive wind turbine, generating and injecting positive and negative sequence modulation coefficient disturbance components; Obtaining the positive and negative sequence voltage disturbance components, the positive and negative sequence current disturbance components, the DC voltage disturbance components and the positive and negative sequence modulation coefficient disturbance components as disturbance signals.

4. The direct drive blower admittance self-test method of claim 1, wherein, S2, collecting data by using the disturbance signal to obtain time-domain signals of the direct-drive wind turbine, comprising: Based on the disturbance signal, collecting small signal components of grid-side converter input signals, grid-side converter output signals, grid-side converter output voltages, point-of-connection voltages and point-of-connection currents; According to the small signal components of the grid-side converter input signals, the grid-side converter output signals, the grid-side converter output voltages, the point-of-connection voltages and the point-of-connection currents, synchronously collecting small signal components of DC-side voltages and DC-side currents; Obtaining the small signal components of the grid-side converter input signals, the grid-side converter output signals, the grid-side converter output voltages, the point-of-connection voltages, the point-of-connection currents, the DC-side voltages and the DC-side currents as time-domain signals of the direct-drive wind turbine.

5. A direct drive blower admittance self-test method according to claim 4, wherein, S3, obtaining frequency-domain data of the direct-drive wind turbine by using fast Fourier transform based on the time-domain signals of the direct-drive wind turbine, comprising: Based on the small signal components of the grid-side converter input signals and the grid-side converter output signals, obtaining positive and negative sequence components of a grid-side converter small signal transfer function by using fast Fourier transform; Based on the small signal components of the grid-side converter output signals, the grid-side converter output voltages, the point-of-connection voltages and the point-of-connection currents, obtaining positive and negative sequence components of a grid inductance and a grid-side converter inductance small signal model by using fast Fourier transform; Based on the small signal components of the DC-side voltages and the DC-side currents, obtaining small signal components of a machine-side converter and a motor system small signal model by using fast Fourier transform; The positive and negative sequence components of the small signal transfer function of the grid-side converter, the positive and negative sequence components of the small signal model of the grid inductance and grid-side converter inductance, and the small signal components of the small signal model of the machine-side converter and motor system are taken as the frequency domain data of the direct-drive wind turbine.

6. A direct drive blower admittance self-test method as claimed in claim 1, wherein, S4, measurement verification is performed based on the frequency domain data of the direct-drive wind turbine, and a direct-drive wind turbine admittance self-test result is obtained, including: Based on the frequency domain data of the direct-drive wind turbine and the small signal model of the grid-side converter, a small signal transfer function of the grid-side converter is obtained. Based on the frequency domain data of the direct-drive wind turbine and the dynamic characteristics of the grid inductance and grid-side converter inductance, a small signal model of the grid inductance and grid-side converter inductance is obtained. Based on the frequency domain data of the direct-drive wind turbine, a small signal model of the machine-side converter and motor system is obtained. Based on the small signal transfer function of the grid-side converter, the small signal model of the grid inductance and grid-side converter inductance, and the small signal model of the machine-side converter and motor system, a small signal model of the direct-drive wind turbine is obtained. Based on the small signal model of the direct-drive wind turbine and a small signal theoretical model of the direct-drive wind turbine, test verification is performed, and a direct-drive wind turbine admittance self-test result is obtained.

7. A direct drive blower admittance self-test method according to claim 6, wherein, The small signal theoretical model of the direct-drive wind turbine is: ， where I gsps is the positive sequence current component at the grid side converter outlet, I gsns is the negative sequence current component at the grid side converter outlet, s is the Laplace operator, j is the imaginary unit, ω1 is the fundamental angular frequency, Y pp is the positive sequence current admittance to the positive sequence voltage, Y pn is the positive sequence current admittance to the negative sequence voltage, Y np is the negative sequence current admittance to the positive sequence voltage, Y nn is the negative sequence current admittance to the negative sequence voltage, V gsps is the positive sequence voltage component at the wind turbine grid connection point, V gsns is the negative sequence voltage component at the wind turbine grid connection point.

8. A direct drive wind turbine admittance self-test device implementing the method of any of claims 1-7, characterized by, including: a disturbance input module, a data acquisition module, a signal processing module, and a measurement verification module; The disturbance input module is configured to generate and inject a disturbance signal based on the direct-drive wind turbine. The data acquisition module is configured to perform data acquisition using the disturbance signal to obtain time domain signals of the direct-drive wind turbine. The signal processing module is configured to obtain frequency domain data of the direct-drive wind turbine using fast Fourier transform based on the time domain signals of the direct-drive wind turbine. The measurement verification module is configured to perform measurement verification based on the frequency domain data of the direct-drive wind turbine to obtain a direct-drive wind turbine admittance self-test result.

9. An electronic device, comprising: including: one or more processors; a storage device having one or more programs stored thereon, when the one or more programs are executed by the one or more processors, the one or more processors implement the method of any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, a computer program is stored thereon, wherein the computer program is executed by one or more processors to implement the method of any one of claims 1 to 7.

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