A wind turbine station-level inertia response characteristics testing method and system

Abstract

The present invention discloses a method and system for testing the inertia response characteristics of wind turbine generator stations. The system includes a signal generator, a high-speed data acquisition processor, a grid-connected measurement and control device, an inertia response control device, an operator server, a voltage converter, a primary-side current converter, a secondary-side current converter, a test signal switching switch, a grid-connected signal control switching switch, a generator-side converter, a grid-side converter, a station power control device, a wind farm energy management system, and related cables and signal lines. This system can accurately test the identification boundary of the inertia response dead zone and comprehensively test multiple indicators, including the lag time of dynamic processes at various frequency change rates, the power response lag time, the rise time, the power peak time, the maximum power after the frequency change, and the power response quantity.

Description

Technical Field

[0001] The present invention relates to the field of wind power generation and control technology, and in particular to a method and system for testing the station-level inertia response characteristics of a wind turbine generator set. Background Art

[0002] Due to the unique randomness, volatility, and intermittency of wind power, the large-scale integration of wind turbines into the grid has significantly changed the energy structure of the power system. The trend toward power electronics in power systems containing wind power has become increasingly prominent, and the characteristics and form of system inertia have changed, showing a clear downward trend. This has led to insufficient inertia support for active power disturbances in the system. Furthermore, under conventional control, new energy generators are decoupled from the grid and cannot provide inertia support for the system. Inertia response is a fundamental resource and key measure for ensuring frequency stability after large-power disturbances in the grid. To improve the inertia response of power systems containing wind power, a series of technical studies have been conducted.

[0003] In their paper "Research on the Inertia System of Frequency Response of High-Proportion Power Electronic Power Systems", Sun Huadong et al. focused on the complex inertia response characteristics of high-proportion power electronic power systems. Based on a thorough analysis of the influencing factors and action mechanisms of the inertia response stage, they expanded the concept of synchronous generator inertia from the perspective of inertia as a physical property that resists system frequency changes, proposed a generalized inertia definition for power systems, and sorted out and classified different inertia forms at the system level, forming a generalized inertia response system and analysis method for system frequency response. In the paper "Measurement and Analysis of Wind Power Inertia and Primary Frequency Regulation in Northeast China Power Grid", Zhang Mei et al. carried out a full-grid disturbance test on wind farm inertia and primary frequency regulation to address the frequency stability problem of high-proportion wind power systems at the DC transmission end of Northeast China Power Grid. Based on the system frequency disturbance test data, they analyzed the dynamic frequency characteristics of Northeast China Power Grid, calculated the equivalent inertia level and frequency extreme characteristic coefficient of Northeast China Power Grid, and quantified the system's ability to resist frequency disturbances. Based on the introduction of the inertia response and primary frequency regulation implementation scheme of the network-source coordinated demonstration wind farm, they compared and analyzed the inertia response characteristics of wind turbines in different implementation schemes, and obtained the primary frequency regulation parameter indicators of different demonstration wind farms. The experiment proved the feasibility and effectiveness of wind power virtual inertia and primary frequency regulation.

[0004] Publicly available literature indicates that the importance of wind farm inertia response and primary frequency regulation has received considerable attention. Some experimental tests have been conducted based on wind farm unit grid-connected conditions. During grid connection, the frequency change rate or amplitude is constrained by the grid frequency and cannot be adjusted according to needs. Furthermore, in actual wind farms, the wind farm inertia response and primary frequency regulation are performed simultaneously, making it impossible to analyze the wind farm inertia response independently of the primary frequency regulation. Therefore, a site-level inertia response characteristic test system for wind turbines was proposed to analyze the actual wind farm inertia response independently of the primary frequency regulation and flexibly adjust the frequency change rate or amplitude based on the needs of the inertia response analysis. Summary of the Invention

[0005] In view of the above existing problems, the present invention is proposed.

[0006] Therefore, the present invention provides a wind turbine station-level inertia response characteristic testing system, which can analyze the actual inertia response of the wind farm independently of the primary frequency modulation action, and flexibly adjust the frequency change rate or amplitude according to the inertia response analysis needs.

[0007] To solve the above technical problems, the present invention provides the following technical solution: a wind turbine station-level inertia response characteristic testing system, comprising:

[0008] Signal generator (2), high-speed data acquisition processor (1), grid-connected measurement and control device (3), inertia response control device (5), operator server (4), voltage converter (20), primary-side current converter (21), secondary-side current converter (22), test signal switching switch (24), grid-connected signal control switching switch (23), machine-side converter (15), grid-side converter (16), station power control device (6), wind farm energy management system (7), and related cables and signal lines.

[0009] As a preferred solution of the wind turbine station-level inertia response characteristic test system of the present invention, wherein: the signal generator (2) outputs V a 、V b 、V c The phases of the three-phase AC signals differ by 120°, and the effective value and frequency of each voltage signal have step mutation and continuous change, thus meeting the requirements of the test signal source; the signal generator (2) outputs V a 、V b 、V c The three-phase AC signal is connected to the grid-connected measurement and control device (3) through the test signal switching switch (24); the signal generator (2) outputs V a 、V b 、V cThe three-phase AC signal is simultaneously connected to the high-speed data acquisition processor (1) through a signal line; the high-speed data acquisition processor (1) acquires V a 、V b 、V c Real-time data of voltage and frequency of three-phase AC signals.

[0010] As a preferred solution of the wind turbine station-level inertia response characteristic test system of the present invention, the high-speed data acquisition processor (1) is connected to the signal generator (2) via a signal line, and is also connected to the low-voltage side of the voltage converter (20) through a grid-connected signal control switching switch (23) and is connected to the secondary-side current converter (22) via a signal line, thereby achieving real-time signal measurement of the three-phase AC voltage and frequency at the wind farm station's real-time power grid connection point.

[0011] As a preferred solution of the wind turbine station-level inertia response characteristic test system of the present invention, the grid-connected measurement and control device (3) is connected to the signal generator (2) through the test signal switching switch (24), and is also connected to the low-voltage side of the voltage converter (20) through the grid-connected signal control switching switch (23) and is connected to the secondary-side current converter (22) through the signal line, thereby realizing the grid-connected measurement and control device (3) testing the real-time power of the wind farm station; when the test signal switching switch (24) is closed and the grid-connected signal control switching switch (23) is open, the grid-connected measurement and control device (3) outputs V of the signal generator (2) for real-time testing. a 、V b 、V c The three-phase AC signal and the real-time output power Pe of the wind farm are transmitted to the inertia response control device (5) via a data bus; when the test signal switching switch (24) is open and the grid-connected signal control switching switch (23) is closed, the grid-connected measurement and control device (3) transmits the low-voltage side three-phase AC signal of the voltage converter (20) under real-time testing and the real-time output power Pe of the wind farm to the inertia response control device (5) via the data bus.

[0012] As a preferred solution of the wind turbine station-level inertia response characteristic test system of the present invention, wherein: the inertia response control device (5) receives the V output by the network measurement and control device (3) a 、V b 、V c The three-phase AC signal is subjected to frequency analysis and converted into three digital quantities of frequency change rate, and then a "three-mid" logic operation is performed to obtain the digital quantity with the middle value from the three digital quantities.

[0013] As a preferred solution of the wind turbine station-level inertia response characteristic test system of the present invention, wherein: the performing of the "three-way" logic operation includes obtaining df / dt by performing the "three-way" logic operation, the unit of df / dt is Hz / s, and df / dt exceeds the dead zone [-Δdf V , Δdf V ], the inertia frequency modulation power command P is formed after the proportion Kp f , P f =K p (df / dt); Where T J is the inertia time constant, which can generally be 8 to 12s, P t is the real-time power of the wind farm, f N is the rated frequency, 50Hz.

[0014] As a preferred solution of the wind turbine station-level inertia response characteristic test system of the present invention, the "three-in-one" logic operation also includes the inertia frequency modulation power instruction P f The real-time power output of the wind farm P e , the power setting value P of the station power control device (6) SG Perform numerical calculation to obtain the control power value ΔP, the calculation formula is: ΔP=P f -P e +P SG The control power value ΔP instruction is transmitted to the wind farm energy management system (7) of the wind turbine groups of different types. After receiving the instruction, the wind farm energy management system (7) issues an adjustment to the machine-side converter (15) and the grid-side converter (16) of each wind turbine of the same type under control. The electromagnetic torque of the corresponding wind turbine changes, thereby realizing the change of the output electric power of the wind turbine.

[0015] The operator server (4) is connected to the inertia response control device (5) via a network signal line. The inertia time constant of the inertia response control device (5) can be set via the operator server (4), and the action process of the inertia response control device (5) can be checked.

[0016] Another object of the present invention is to provide a method for testing the inertia response characteristics of a wind turbine generator set at a station level, which can solve the problem that the inertia response characteristics testing method of a wind turbine generator set at a station level cannot be implemented in the prior art by realizing a wind turbine generator set station level inertia response characteristics testing system.

[0017] As a preferred solution of the wind turbine station-level inertia response characteristic testing method described in the present invention, the method includes: collecting data from the generator and processor, and preprocessing the data; performing frequency analysis on the output three-phase AC signal and converting it into three digital quantities of frequency change rate, and then performing a "three-center" logical operation; transmitting the instruction to the wind farm energy management system, and implementing the next step of operation through the wind farm energy management system.

[0018] A computer device includes a memory and a processor, wherein the memory stores a computer program, and is characterized in that when the processor executes the computer program, steps of a wind turbine station-level inertia response characteristic test system are implemented.

[0019] A computer-readable storage medium stores a computer program thereon, wherein when the computer program is executed by a processor, steps of a wind turbine station-level inertia response characteristic test system are implemented.

[0020] The beneficial effects of the present invention are as follows: the present invention can determine the performance index of the inertia response control device (5) through experiments, accurately test the identification boundary of the inertia response dead zone, comprehensively test the lag time of the dynamic process when the grid frequency changes rapidly away from 50Hz (various different frequency change rates), power response lag time, rise time, power peak time, maximum power after frequency change, power response amount and other indicators, as well as whether the wind farm performs power regulation when returning to 50Hz and whether the station power is stable; in maintaining the stability of the grid frequency, the present invention plays a guiding role in formulating control strategies and response measures for wind farms. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 A schematic structural diagram of a wind turbine station-level inertia response characteristics testing system provided by one embodiment of the present invention.

[0023] Figure 2 An electric power signal recording diagram of a wind turbine station-level inertia response characteristic test system provided by one embodiment of the present invention.

[0024] Figure 3 The present invention provides an electric power signal recording diagram during a negative frequency speed change response test of a wind turbine station-level inertia response characteristic test system according to an embodiment of the present invention.

[0025] Figure 4 The present invention provides an electric power signal recording diagram during a positive frequency variable speed response test of a wind turbine station-level inertia response characteristic test system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0026] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the following detailed description of the specific embodiments of the present invention is given in conjunction with the accompanying drawings. It is obvious that the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in this field without creative work should fall within the scope of protection of the present invention.

[0027] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0028] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0029] The present invention is described in detail with reference to schematic diagrams. For ease of illustration, cross-sectional views of device structures may be partially enlarged and not to scale when describing embodiments of the present invention. Furthermore, the schematic diagrams are merely illustrative and should not limit the scope of the present invention. Furthermore, in actual production, the three-dimensional dimensions of length, width, and depth should be included.

[0030] In the description of the present invention, it should be noted that the terms "upper, lower, inner, and outer" and other references to orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first, second, or third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] In this disclosure, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be interpreted broadly. For example, they may refer to fixed, removable, or integral connections. They may also refer to mechanical, electrical, or direct connections, indirect connections through an intermediary, or internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this disclosure.

[0032] Example 1

[0033] Reference Figure 1 , which is the first embodiment of the present invention, provides a wind turbine station-level inertia response characteristic testing system, comprising:

[0034] like Figure 1 As shown, a wind turbine station-level inertia response characteristic test system and method includes a signal generator (2), a high-speed data acquisition processor (1), a grid-connected measurement and control device (3), an inertia response control device (5), an operator server (4), a voltage converter (20), a primary-side current converter (21), a secondary-side current converter (22), a test signal switching switch (24), a grid-connected signal control switching switch (23), a machine-side converter (15), a grid-side converter (16), a station power control device (6), a wind farm energy management system (7), and related cables and signal lines.

[0035] Figure 1 Among them, (3), (4) and (5) are respectively an HPH-500 grid-connected measurement and control device, an HPH-3200 core server and an HPH-3100 management server, all of which can process data independently and exchange data with each other; frequency measurement requires measuring the period, and frequency change rate requires measuring the time between two frequency points. The superposition of the frequency measurement period and the time between the two frequency points causes the entire measurement process to take longer; the independent data processing functions of (3), (4) and (5) can realize fast data processing and solve the problem of accurate measurement of frequency and its change rate.

[0036] The signal generator (2) outputs V a 、V b 、V c The phases of the three-phase AC signals differ by 120°, and the effective value and frequency of each voltage signal have step mutation and continuous change, thus meeting the requirements of the test signal source; the signal generator (2) outputs V a 、V b 、V c The three-phase AC signal is connected to the grid-connected measurement and control device (3) through the test signal switching switch (24); the signal generator (2) outputs V a 、V b 、Vc The three-phase AC signal is simultaneously connected to the high-speed data acquisition processor (1) through a signal line; the high-speed data acquisition processor (1) acquires V a 、V b 、V c Real-time data such as voltage and frequency of three-phase AC signals;

[0037] The high-speed data acquisition processor (1) is connected to the signal generator (2) via a signal line, and is also connected to the low-voltage side of the voltage converter (20) via a grid-connected signal control switch (23), and is connected to the secondary-side current converter (22) via a signal line, thereby realizing the real-time power P of the wind farm station. e Real-time signal measurement of three-phase AC voltage and frequency at the grid connection point;

[0038] The grid-connected measurement and control device (3) is connected to the signal generator (2) via the test signal switching switch (24), and is also connected to the low-voltage side of the voltage converter (20) via the grid-connected signal control switching switch (23), and is connected to the secondary-side current converter (22) via the signal line, thereby enabling the grid-connected measurement and control device (3) to monitor the real-time power P of the wind farm station. e When the test signal switching switch (24) is closed and the grid-connected signal control switching switch (23) is open, the grid-connected measurement and control device (3) transmits the three-phase AC signals Va, Vb, and Vc output by the real-time test signal generator (2) and the real-time output power Pe of the wind farm to the inertia response control device (5) through the data bus; when the test signal switching switch (24) is open and the grid-connected signal control switching switch (23) is closed, the grid-connected measurement and control device (3) transmits the low-voltage side three-phase AC signals of the real-time test voltage converter (20) and the real-time output power Pe of the wind farm to the inertia response control device (5) through the data bus;

[0039] The inertia response control device (5) receives the V output by the network measurement and control device (3) a 、V b 、V c The three-phase AC signal is subjected to frequency analysis and converted into three digital quantities of frequency change rate, and then a "three-mid" logic operation is performed, that is, the mid-value of the three digital quantities is taken; df / dt can be obtained. The unit of df / dt is Hz / s. If df / dt exceeds the dead zone [-Δdf V , Δdf V ], the inertia frequency modulation power command P is formed after the proportion Kp f , P f =K p (df / dt); Where T J is the inertia time constant, which can generally be 8 to 12s, P tis the real-time power of the wind farm, f N is the rated frequency, 50Hz; inertia frequency modulation power command P f The real-time power output of the wind farm P e , the power given value PSG of the station power control device (6) is numerically calculated to obtain the control power value ΔP, and the calculation formula is: ΔP=P f -P e +P SG The control power value ΔP instruction is transmitted to the wind farm energy management system (7) of different types of wind turbine groups. After receiving the instruction, the wind farm energy management system (7) adjusts the machine-side converter (15) and the grid-side converter (16) of each wind turbine of the same type under its control, and the electromagnetic torque of the corresponding wind turbine changes, thereby achieving a change in the output electric power of the wind turbine.

[0040] The operator server (4) is connected to the inertia response control device (5) via a network signal line, and the inertia time constant T of the inertia response control device (5) can be set via the operator server (4). J , check the action process of the inertia response control device (5).

[0041] The operator server (4) can check that the inertia response control device (5) receives the V signal from the signal generator (2). a 、V b 、V c When the frequency of the signal decreases from 50 Hz at a frequency change rate of df / dt = -0.04 Hz / s, -0.05 Hz / s, and -0.06 Hz / s, respectively, away from 50 Hz, the error between the frequency change rate df / dt identified by the inertia response control device (5) and the input standard frequency change rate is shown in Table 3. From Table 3, it can be found that the frequency change rate df / dt identified by the inertia response control device (5) corresponding to df / dt = -0.04 Hz / s is dt=-0.04±0.003Hz / s; corresponding to df / dt=-0.05Hz / s, the frequency change rate df / dt=-0.05±0.003Hz / s identified by the inertia response control device (5); corresponding to df / dt=-0.06Hz / s, the frequency change rate df / dt=-0.06±0.003Hz / s identified by the inertia response control device (5); its identification error is 0.003Hz / s.

[0042] Example 2

[0043] Reference Figures 1-4 , which is an embodiment of the present invention, provides a wind turbine station-level inertia response characteristic testing system. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through experiments.

[0044] like Figure 1As shown, a wind turbine station-level inertia response characteristic test system and method includes a signal generator (2), a high-speed data acquisition processor (1), a grid-connected measurement and control device (3), an inertia response control device (5), an operator server (4), a voltage converter (20), a primary-side current converter (21), a secondary-side current converter (22), a test signal switching switch (24), a grid-connected signal control switching switch (23), a machine-side converter (15), a grid-side converter (16), a station power control device (6), a wind farm energy management system (7), and related cables and signal lines.

[0045] Figure 1 Among them, (3), (4) and (5) are respectively an HPH-500 grid-connected measurement and control device, an HPH-3200 core server and an HPH-3100 management server, all of which can process data independently and exchange data with each other; frequency measurement requires measuring the period, and frequency change rate requires measuring the time between two frequency points. The superposition of the frequency measurement period and the time between the two frequency points causes the entire measurement process to take longer; the independent data processing functions of (3), (4) and (5) can realize fast data processing and solve the problem of accurate measurement of frequency and its change rate.

[0046] Signal generator (2) outputs V a 、V b 、V c The phases of the three-phase AC signals differ by 120°, and the effective values ​​and frequencies of each voltage signal have step mutations and continuous changes, thus meeting the requirements of the signal source. The performance index requirements of the signal generator (2) are as follows: the voltage output range is wider than 0-130V, and the output voltage error is less than ±0.1%; the frequency output range covers 1-100Hz, the frequency error is less than 0.002Hz, the phase output range is 0-360°, the phase output error is less than ±0.1°, and the voltage and frequency curves can be edited; the embodiment signal generator (2) uses the SVS-1000D signal generator.

[0047] The accuracy of the high-speed data acquisition processor (1) should be no less than 0.2, the sampling frequency should be no less than 20kHz, and the bandwidth should be no less than 10MHz. In the embodiment, the high-speed data acquisition processor (1) adopts the SIRIUS-R8D portable record analyzer.

[0048] Take a wind farm with three different types of wind turbines in a 110kV booster station as an example. The wind farm energy management system (7) of the first group of wind turbines controls 25 Goldwind GW150-3000 units, the wind farm energy management system (7) of the second group of wind turbines controls 13 Sany SE16032 units, and the wind farm energy management system (7) of the third group of wind turbines controls 12 Mingyang MySE3.2 units. The installed capacity of the entire wind farm is 130MW.N The basic information of the wind farm units is shown in Table 1. The inertia time constant of the wind farm is T J =10s, inertia response dead zone [-Δdf V , Δdf V ] is [-0.05, 0.05], that is, Δdf V =0.05Hz.

[0049] Table 1 Basic information of wind farm

[0050]

[0051] The wind farm unit is connected to the grid and the signal generator (2) is in a state where it can output frequency signals, and the high-speed data acquisition processor (1) is in a state where it can browse and store data. The test signal switching switch (24) is closed and the grid-connected signal control switching switch (23) is open. The V a 、V b 、V c The signal sources are set to have a frequency of 50 Hz, a voltage signal amplitude of 57.735 V, and a phase difference of 120°, that is, V a 、V b 、V c The signal sources are 0°, -120°, and 120°, as shown in Table 2;

[0052] Table 2 Signal generator parameters

[0053] Serial number name symbol Amplitude Phase frequency unit / / V ° Hz 1 Phase A signal <![CDATA[V a ]]> 57.735 0° 50 2 Phase B signal <![CDATA[V b ]]> 57.735 -120° 50 3 C-phase signal <![CDATA[V c ]]> 57.735 120° 50

[0054] 1. Frequency change rate response dead zone test

[0055] (1) Signal generator (2) V a 、V b 、V c The effective value, amplitude, frequency and phase of each phase signal voltage of the signal source remain unchanged, as shown in Table 2;

[0056] (2) The high-speed data acquisition processor (1) enters the data acquisition storage state; the V a 、V b 、V c The frequency of the signal decreases from 50 Hz at a rate of df / dt = -0.04 Hz / s and returns to 50 Hz after a delay of T = 10 seconds.

[0057] (3) The high-speed data acquisition processor (1) enters the data acquisition storage state; the V a 、V b 、V cThe frequency of the signal decreases from 50 Hz at a rate of df / dt = -0.05 Hz / s and returns to 50 Hz after a delay of T = 10 seconds.

[0058] (4) The high-speed data acquisition processor (1) enters the data acquisition storage state; the V a 、V b 、V c The frequency of the signal decreases from 50 Hz at a rate of df / dt = -0.06 Hz / s and recovers to 50 Hz after a delay of T = 10 seconds.

[0059] (5) The frequency signal of the signal generator (2) and the wind farm electric power signal recorded by the high-speed data acquisition processor (1) are shown in the following figure: Figure 2 As shown, curve 1 is the wind farm power P t , Curve 2 signal generator (2) V a 、V b 、V c The frequency f is obtained by “taking the middle of three” the frequency signal of the signal source; Figure 2 From the test data, Figure 2 From the changing trend, the frequency decreases at a rate of df / dt = -0.04Hz / s in the inertia response dead zone [-Δdf V , Δdf V ], that is, within [-0.05, 0.05], the wind farm does not perform power regulation; the frequency decreases at a rate of df / dt = -0.05Hz / s in the inertia response dead zone [-Δdf V , Δdf V ] boundary, that is, [-0.05, 0.05] boundary, the wind farm sometimes performs power regulation and sometimes does not perform power regulation; the frequency decreases at a rate of change of df / dt=-0.06Hz / s in the inertia response dead zone [-Δdf V , Δdf V ], that is, outside [-0.05, 0.05], the wind farm performs power regulation. When returning to 50Hz, the wind farm does not perform power regulation and the wind farm station power is stable.

[0060] (6) From the operator server (4), it can be seen that when the frequency of the Va, Vb, and Vc signals received by the signal generator (2) decreases from 50 Hz at a frequency change rate of df / dt = -0.04 Hz / s, -0.05 Hz / s, and -0.06 Hz / s, the frequency change rate df / dt recognized by the inertia response control device (5) is shown in Table 3. From Table 3, it can be seen that the frequency change rate df / dt corresponding to df / dt = -0.04 Hz / s is the same as that of the inertia response control device ( 5) The identified frequency change rate df / dt = -0.04 ± 0.003 Hz / s; corresponding to df / dt = -0.05 Hz / s, the frequency change rate df / dt identified by the inertia response control device (5) is -0.05 ± 0.003 Hz / s; corresponding to df / dt = -0.06 Hz / s, the frequency change rate df / dt identified by the inertia response control device (5) is -0.06 ± 0.003 Hz / s; its identification error is 0.003 Hz / s.

[0061] (7) The frequency change rate df / dt identified by the inertia response control device (5) exceeds the inertia response dead zone [-Δdf V , Δdf V ], that is, [-0.05, 0.05], the inertia frequency modulation power instruction P issued by the inertia response control device (5) f , the wind farm power changes accordingly. The test data is shown in Table 4. The inertia frequency modulation power command P in Table 4 f =K p (df / dt), where Where T J The inertia time constant can be 8 to 12 seconds. J =10s, P t is the real-time power of the wind farm before the inertia frequency regulation power command is issued, f N The rated frequency is 50Hz; ΔP′ t The maximum power response when the maximum frequency change rate identified by the inertia response control device (5) is -0.053 Hz / s, ΔP″ t The maximum power response amount when the maximum frequency change rate identified by the inertia response control device (5) is -0.063 Hz / s.

[0062] Table 3 Frequency change rate response dead zone dynamic test data table

[0063]

[0064]

[0065] Table 4 Frequency change rate response dead zone dynamic test data table

[0066]

[0067] 2. Frequency speed response test

[0068] 2.1 Negative frequency speed change response test

[0069] (1) Signal generator (2) V a 、V b 、V c The effective value, amplitude, frequency and phase of each phase signal voltage of the signal source remain unchanged, as shown in Table 1;

[0070] (2) The high-speed data acquisition processor (1) enters the data acquisition storage state; the V a 、V b 、V c The frequency of the signal decreases at a rate of df / dt = -0.5 Hz / s and recovers to 50 Hz after a delay of T = 4 seconds.

[0071] (3) The frequency signal of the signal generator (2) and the wind farm electric power signal recorded by the high-speed data acquisition processor (1) are shown in the following figure: Figure 3 As shown, curve 1 is the wind farm power P t , Curve 2 signal generator (2) V a 、V b 、V c The frequency f is obtained by performing "three-way centering" on the frequency signal of the signal source.

[0072] like Figure 3 、 Figure 4 As shown, the invention can test the inertia response control device (5) when it receives the V signal from the signal generator (2). a 、V b 、V c When the signal frequency exceeds the dead zone of [-0.05, 0.05] Hz / s from 50 Hz and decreases or increases at a certain frequency change rate away from 50 Hz, the wind farm power will increase or decrease accordingly. However, the wind farm power will not change when the frequency returns to 50 Hz.

[0073] like Figure 3 、 Figure 4 As shown, the invention can test the lag time, rise time, power peak time, peak power, adjustment time, stable power after frequency change, power response amount, inertia frequency modulation power instruction, power before frequency recovery to 50Hz, and power after frequency recovery to 50Hz of the inertia response control process.

[0074] 2.3 Dynamic response parameter analysis

[0075] According to the test recording curve Figure 3 、 Figure 4 , the adjustment process parameters can be obtained as shown in Table 4. Figure 3 、 Figure 4 From the changing trend of the signal generator (2), we can find that the V a 、V b 、V c When the frequency change rate of the signal source exceeds the deadband and moves away from 50 Hz, the wind farm adjusts its power toward 50 Hz. When the frequency returns to 50 Hz, the wind farm does not adjust its power, and the power at the site remains stable. Table 5 comprehensively captures several indicators, including power response lag time, rise time, power peak time, and power response, for wind farms experiencing rapid grid frequency changes (at various frequency change rates; in this example, the frequency change rates are -0.5 Hz / s and 0.5 Hz / s). These indicators provide key parameters for developing control strategies and countermeasures to maintain grid frequency stability.

[0076] Table 5 Dynamic test data of frequency uniform speed change test

[0077]

[0078] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

[0079] Example 3

[0080] The third embodiment of the present invention is different from the first two embodiments in that:

[0081] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0082] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiment of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal translation scripting language JavaScript, etc.

[0083] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0084] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0085] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0086] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0087] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A wind turbine station-level inertia response characteristics test system, characterized by: include, Signal generator (2), high-speed data acquisition processor (1), grid-connected measurement and control device (3), inertia response control device (5), operator server (4), voltage converter (20), primary-side current converter (21), secondary-side current converter (22), test signal switching switch (24), grid-connected signal control switching switch (23), machine-side converter (15), grid-side converter (16), station power control device (6), wind farm energy management system (7), and corresponding cables and signal lines; The signal generator (2) outputs V a 、V b 、V c The phases of the three-phase AC signals differ by 120°, and the effective value and frequency of each voltage signal have step mutation and continuous change, thus meeting the requirements of the test signal source; the signal generator (2) outputs V a 、V b 、V c The three-phase AC signal is connected to the grid-connected measurement and control device (3) through the test signal switching switch (24); the signal generator (2) outputs V a 、V b 、V c The three-phase AC signal is simultaneously connected to the high-speed data acquisition processor (1) through a signal line; the high-speed data acquisition processor (1) acquires V a 、V b 、V c Real-time data of voltage and frequency of three-phase AC signals; The inertia response control device (5) receives the V output by the grid-connected measurement and control device (3) a 、V b 、V c The three-phase AC signal is subjected to frequency analysis and converted into three digital quantities of frequency change rate, and then a "three-mid" logic operation is performed to obtain the digital quantity with the middle value from the three digital quantities; The inertia response control device (5) receives the V signal from the signal generator (2). a 、V b 、V c When the signal frequency exceeds the dead zone of [-0.05, 0.05] Hz / s from 50 Hz and decreases or increases at a certain frequency change rate away from 50 Hz, the wind farm power will increase or decrease accordingly. It is also determined whether the wind farm power will change during the process of frequency return to 50 Hz. At the same time, the lag time, rise time, power peak time, peak power, adjustment time, stable power after frequency change, power response, inertia frequency regulation power command, power before frequency recovery to 50 Hz, and power after frequency recovery to 50 Hz of the inertia response control process are tested.

2. A wind turbine station-level inertia response characteristic testing system according to claim 1, characterized in that: The high-speed data acquisition processor (1) is connected to the signal generator (2) via a signal line, and is also connected to the low-voltage side of the voltage converter (20) via a grid-connected signal control switching switch (23), and is connected to the secondary-side current converter (22) via a signal line, thereby achieving real-time signal measurement of the three-phase AC voltage and frequency at the wind farm station's real-time power grid-connected point.

3. A wind turbine station-level inertia response characteristic testing system according to claim 2, characterized in that: The grid-connected measurement and control device (3) is connected to the signal generator (2) via the test signal switching switch (24), is also connected to the low-voltage side of the voltage converter (20) via the grid-connected signal control switching switch (23), and is connected to the secondary-side current converter (22) via a signal line, thereby enabling the grid-connected measurement and control device (3) to test the real-time power of the wind farm station; when the test signal switching switch (24) is closed and the grid-connected signal control switching switch (23) is open, the grid-connected measurement and control device (3) outputs V of the signal generator (2) for real-time testing. a 、V b 、V c The three-phase AC signal and the real-time output power Pe of the wind farm are transmitted to the inertia response control device (5) via a data bus; when the test signal switching switch (24) is open and the grid-connected signal control switching switch (23) is closed, the grid-connected measurement and control device (3) transmits the low-voltage side three-phase AC signal of the voltage converter (20) under real-time testing and the real-time output power Pe of the wind farm to the inertia response control device (5) via the data bus.

4. A wind turbine station-level inertia response characteristic testing system according to claim 3, characterized in that: The "three-way" logic operation includes obtaining df / dt by performing the "three-way" logic operation. The unit of df / dt is Hz / s. After df / dt exceeds the dead zone, it is converted into the inertia frequency modulation power instruction P after the proportion Kp. f , P f =K p (df / dt); Where T J is the inertia time constant, which is 8 to 12s, P t is the real-time power of the wind farm, f N The rated frequency is 50Hz.

5. The wind turbine station-level inertia response characteristic testing system according to claim 4, characterized in that: The "three-in-one" logic operation also includes the inertia frequency modulation power instruction P f The real-time power output of the wind farm P e , the power setting value P of the station power control device (6) SG Perform numerical calculation to obtain the control power value ΔP, the calculation formula is: ΔP=P f -P e +P SG The control power value ΔP instruction is transmitted to the wind farm energy management system (7) of the wind turbine groups of different types. After receiving the instruction, the wind farm energy management system (7) issues an adjustment to the machine-side converter (15) and the grid-side converter (16) of each wind turbine of the same type under control. The electromagnetic torque of the corresponding wind turbine changes, thereby realizing the change of the output electric power of the wind turbine. The operator server (4) is connected to the inertia response control device (5) via a network signal line. The inertia time constant of the inertia response control device (5) can be set via the operator server (4), and the action process of the inertia response control device (5) can be checked.

6. A method using a wind turbine station-level inertia response characteristic testing system according to any one of claims 1 to 5, characterized in that: Collect generator and processor data and pre-process the data; The output three-phase AC signal is subjected to frequency analysis and converted into three digital quantities of frequency change rate, and then a "three-in-one" logic operation is performed; The instructions are transmitted to the wind farm energy management system, and the next step of operation is implemented through the wind farm energy management system.

7. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to claim 6 are implemented.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to claim 6 are implemented.

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