Inertia and damping coefficient detection method, system and equipment for power electronic equipment

Abstract

The inertia and damping coefficient detection method, system and equipment of power electronic equipment disclosed in the present application relate to the field of power electronic technology. The method includes obtaining the AC voltage and AC current of the power electronic equipment to be tested in real time; determining the frequency and frequency change rate based on the AC voltage; determining the active power based on the AC voltage and AC current; generating a disturbance signal based on the frequency, active power, AC voltage or AC current; when the disturbance signal is 0, no processing is performed; when the disturbance signal is 1, based on the frequency, frequency change rate and active power, the frequency vector, frequency change rate vector and active power vector during the disturbance are obtained; based on the frequency vector, frequency change rate vector and active power vector, the inertia coefficient and damping coefficient of the power electronic equipment to be tested are determined. The present application can realize the online real-time and accurate detection of the inertia and damping coefficient of the power electronic equipment, so as to more comprehensively reflect the dynamic behavior of the power electronic equipment.

Description

Technical Field

[0001] The present application relates to the field of power electronics technology, and in particular to a method, system and device for detecting inertia and damping coefficient of power electronics equipment. Background Art

[0002] With the continuous penetration of renewable energy and power electronics technology, the power grid is undergoing a profound transformation from being dominated by traditional synchronous machines to being dominated by power electronic equipment. In traditional power systems, synchronous motors and other equipment effectively resist frequency fluctuations and ensure stable system operation by providing physical inertia and damping. However, the large-scale grid connection of new energy sources has led to a gradual decrease in the proportion of synchronous motors in the power grid, which in turn has caused a significant weakening of the system's equivalent inertia and damping. This change has increased the sensitivity of new power systems to frequency and voltage disturbances, and the risk of oscillation and instability has also increased. Therefore, it is crucial to effectively detect and evaluate the inertia and damping coefficients of power electronic equipment and quantify its grid support capabilities to ensure the stability of high-proportion power electronic systems.

[0003] The existing inertia and damping coefficient detection of power electronic equipment mostly relies on specialized test equipment such as power grid simulators. These devices can simulate the equipment grid connection process and provide a basis for parameter measurement. However, this method has the following obvious shortcomings: (1) Real-time measurement is difficult: The inertia and damping of power electronic equipment are time-varying, which makes it a major challenge to accurately measure them in real time during actual operation. (2) Idealized detection environment: The test conditions of the power grid simulator are relatively idealized, and it is difficult to fully reflect the dynamic characteristics of the equipment in actual power grid operation. Summary of the invention

[0004] The purpose of this application is to provide a method, system and device for detecting the inertia and damping coefficient of power electronic equipment, which can realize online real-time and accurate detection of the inertia and damping coefficient of power electronic equipment, thereby more comprehensively reflecting the dynamic performance of the power electronic equipment.

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] In a first aspect, the present application provides a method for detecting inertia and damping coefficient of power electronic equipment, comprising:

[0007] Obtain the AC voltage and AC current of the power electronic equipment to be tested in real time;

[0008] determining a frequency and a rate of change of frequency based on the AC voltage;

[0009] determining active power based on the AC voltage and the AC current;

[0010] generating a disturbance signal based on the frequency, the active power, the AC voltage or the AC current;

[0011] When the disturbance signal is 0, no processing is performed;

[0012] When the disturbance signal is 1, based on the frequency, the frequency change rate and the active power, a frequency vector, a frequency change rate vector and an active power vector during the disturbance are obtained;

[0013] Based on the frequency vector, the frequency change rate vector and the active power vector, the inertia coefficient and the damping coefficient of the power electronic equipment to be tested are determined.

[0014] Optionally, the method for detecting inertia and damping coefficient of power electronic equipment further includes:

[0015] Based on the frequency vector, the frequency change rate vector and the active power vector, a determination coefficient of the power electronic equipment to be tested is determined, and the determination coefficient is used to judge the validity of the inertia coefficient and the damping coefficient.

[0016] Optionally, determining the frequency and the frequency change rate based on the AC voltage of the power electronic equipment to be tested includes:

[0017] Obtaining a phase difference signal based on the AC voltage;

[0018] Performing filtering and smoothing processing on the phase difference signal to obtain an error signal;

[0019] Performing oscillation adjustment on the error signal to generate a feedback signal;

[0020] The frequency and the rate of change of frequency are determined based on the feedback signal.

[0021] Optionally, the determining the active power based on the AC voltage of the power electronic equipment to be tested and the AC current of the power electronic equipment to be tested comprises:

[0022] Using a phase-locked loop to obtain a phase angle based on the AC voltage of the power electronic equipment to be tested;

[0023] Perform coordinate transformation on the AC voltage and the phase angle of the power electronic equipment to be tested to obtain the AC voltage of the power electronic equipment to be tested. Shaft voltage components and Shaft voltage component;

[0024] The AC current of the power electronic equipment to be tested and the phase angle are transformed to obtain the AC current of the power electronic equipment to be tested. Shaft current components and Shaft current component;

[0025] Based on the AC voltage of the power electronic equipment to be tested Shaft voltage components and Shaft voltage components and AC current of the power electronic equipment under test Shaft current components and Shaft current components, determine the active power.

[0026] Optionally, the coordinate transformation is: transforming the AC voltage and AC current of the power electronic equipment to be tested from the three-phase static Coordinate system transformation to rotation Coordinate system.

[0027] Optionally, the generating a disturbance signal based on the frequency, the active power, the AC voltage or the AC current includes:

[0028] Determine the difference between the current frequency, active power, AC voltage or AC current and the previous frequency, active power, AC voltage or AC current;

[0029] Determine whether the absolute value of the difference is less than a set threshold value, and obtain a determination result;

[0030] When the judgment result is yes, the disturbance signal is 0;

[0031] When the judgment result is no, the disturbance signal is 1.

[0032] Optionally, determining the inertia coefficient and damping coefficient of the power electronic equipment to be tested based on the frequency vector, the frequency change rate vector and the active power vector includes:

[0033] The frequency vector, the frequency change rate vector and the active power vector are normalized to obtain a normalized frequency vector, a normalized frequency change rate vector and a normalized active power vector;

[0034] Perform deviation normalization processing on the per-unit frequency vector to obtain a per-unit frequency deviation vector;

[0035] The normalized frequency deviation vector, the normalized frequency change rate vector and the normalized active power vector are subjected to regression calculation by the least square method to obtain the inertia coefficient and damping coefficient of the power electronic equipment to be tested.

[0036] In a second aspect, the present application provides an inertia and damping coefficient detection system for power electronic equipment, comprising:

[0037] A detection device, connected to the power electronic equipment to be tested, for obtaining the AC voltage and AC current of the power electronic equipment to be tested;

[0038] An inertia and damping coefficient detection device is connected to the detection device, and implements any one of the above-mentioned methods for detecting inertia and damping coefficient of power electronic equipment based on the AC voltage and AC current of the power electronic equipment to be tested, so as to obtain the inertia coefficient and damping coefficient of the power electronic equipment to be tested.

[0039] Optionally, the inertia and damping coefficient detection device comprises:

[0040] A frequency and change rate calculation module, connected to the detection device, for determining the frequency and the frequency change rate based on the AC voltage;

[0041] an active power calculation module, connected to the detection device, and used to determine the active power based on the AC voltage and the AC current;

[0042] A disturbance monitoring module, connected to the frequency and change rate calculation module, the detection device or the active power calculation module, and used to generate a disturbance signal based on the frequency, the active power, the AC voltage or the AC current;

[0043] a data recording module, connected to the frequency and change rate calculation module, the active power calculation module and the disturbance monitoring module, and used to obtain the frequency vector, the frequency change rate vector and the active power vector during the disturbance period based on the frequency, the frequency change rate and the active power when the disturbance signal is 1;

[0044] The inertia and damping coefficient calculation module is connected to the data recording module, and is used to determine the inertia coefficient and damping coefficient of the power electronic equipment to be tested based on the frequency vector, the frequency change rate vector and the active power vector.

[0045] In a third aspect, the present application provides a computer device, comprising:

[0046] A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement any one of the above-mentioned methods for detecting inertia and damping coefficient of power electronic equipment.

[0047] According to the specific embodiments provided in this application, this application has the following technical effects:

[0048] The present application provides a method, device and medium for detecting the inertia and damping coefficient of power electronic equipment. By acquiring the AC voltage and AC current of the power electronic equipment to be tested in real time, the inertia and damping coefficient of the power electronic equipment can be determined, which can solve the problem that the real-time changes of the inertia and damping coefficient of the power electronic equipment in actual operation are difficult to accurately measure, thereby realizing real-time and accurate measurement of the power electronic equipment, which is helpful for evaluating the stability of the power grid. By detecting the disturbance signal generated based on frequency, active power, AC voltage or AC current as a small disturbance, no additional disturbance is introduced, which ensures the operational stability of the power grid and power electronic equipment, and can solve the problem that the power grid simulator is difficult to fully reflect the dynamic characteristics of the equipment in the actual power grid operation, thereby fully reflecting the dynamic characteristics of the measured power electronic equipment under power grid fluctuations. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0050] Figure 1 It is a flow chart of a method for detecting inertia and damping coefficient of power electronic equipment in one embodiment of the present application;

[0051] Figure 2 It is a structural schematic diagram of an inertia and damping coefficient detection system for power electronic equipment provided by an embodiment of the present application;

[0052] Figure 3 It is a schematic diagram of the structure of a frequency and change rate calculation module provided in an embodiment of the present application;

[0053] Figure 4 It is a structural schematic diagram of an active power calculation module provided in an embodiment of the present application;

[0054] Figure 5 is a schematic diagram of the structure of a disturbance monitoring module provided in an embodiment of the present application;

[0055] Figure 6 It is a schematic diagram of the structure of a data recording module provided in an embodiment of the present application;

[0056] Figure 7 It is a schematic diagram of the structure of an inertia and damping coefficient calculation module provided in an embodiment of the present application;

[0057] Figure 8 It is a schematic diagram of normalized active power and frequency simulation results recorded after a disturbance occurs provided by an embodiment of the present application;

[0058] Fig. 9 It is a simulation result diagram of inertia coefficient, damping coefficient and determination coefficient provided in one embodiment of the present application;

[0059] Fig.10 It is a structural diagram of a computer device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0060] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0061] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0062] In an exemplary embodiment, Figure 1 As shown, a method for detecting inertia and damping coefficient of power electronic equipment is provided, comprising the following steps 100 to 104. Among them:

[0063] Step 100, obtaining the AC voltage and AC current of the power electronic equipment to be tested in real time;

[0064] Step 101, determining the frequency and the frequency change rate based on the AC voltage;

[0065] Step 102, determining active power based on the AC voltage and the AC current;

[0066] Step 103, generating a disturbance signal based on frequency, active power, AC voltage or AC current; when the disturbance signal is 0, no processing is performed; when the disturbance signal is 1, based on frequency, frequency change rate and active power, a frequency vector, a frequency change rate vector and an active power vector during the disturbance period are obtained;

[0067] Step 104: Determine the inertia coefficient and damping coefficient of the power electronic equipment to be tested based on the frequency vector, the frequency change rate vector and the active power vector.

[0068] By implementing the above steps 100 to 104 , it is possible to realize online, real-time and accurate detection of the inertia and damping coefficient of the power electronic equipment, thereby more comprehensively reflecting the dynamic performance of the power electronic equipment.

[0069] In another exemplary embodiment of the present application, a method for determining frequency and frequency change rate based on AC voltage is provided, as follows:

[0070] The AC voltage is compared with the feedback signal in the phase detector to obtain a phase difference signal; the phase difference signal is filtered and smoothed to obtain an error signal; the error signal is oscillated and adjusted to generate a feedback signal; the frequency and frequency change rate are determined based on the feedback signal.

[0071] In another exemplary embodiment of the present application, a method for determining active power based on the AC voltage of the power electronic equipment to be tested and the AC current of the power electronic equipment to be tested is provided, as follows:

[0072] A phase-locked loop is used to obtain the phase angle based on the AC voltage of the power electronic equipment to be tested; the AC voltage and phase angle of the power electronic equipment to be tested are transformed to obtain the AC voltage of the power electronic equipment to be tested. Shaft voltage components and axis voltage component; coordinate transformation is performed on the AC current and phase angle of the power electronic equipment to be tested to obtain the AC current of the power electronic equipment to be tested. Shaft current components and Shaft current component; based on the AC voltage of the power electronic equipment to be tested Shaft voltage components and Shaft voltage components and AC current of the power electronic equipment under test Shaft current components and Shaft current components, determine the active power.

[0073] In another exemplary embodiment of the present application, a method for generating a disturbance signal based on frequency, active power, AC voltage or AC current is provided, as follows:

[0074] Determine the difference between the current frequency, active power, AC voltage or AC current and the previous frequency, active power, AC voltage or AC current;

[0075] It is determined whether the absolute value of the difference is less than a set threshold value to obtain a determination result. When the determination result is yes, the disturbance signal is 0; when the determination result is no, the disturbance signal is 1.

[0076] In another exemplary embodiment of the present application, a method for determining the inertia coefficient and damping coefficient of the power electronic equipment to be tested based on the frequency vector, the frequency change rate vector and the active power vector is provided, as follows:

[0077] The frequency vector, the frequency change rate vector and the active power vector are normalized to obtain the normalized frequency vector, the normalized frequency change rate vector and the normalized active power vector; the normalized frequency vector is subjected to deviation normalization to obtain the normalized frequency deviation vector; the normalized frequency deviation vector, the normalized frequency change rate vector and the normalized active power vector are subjected to regression calculation by the least square method and other methods to obtain the inertia coefficient and damping coefficient of the power electronic equipment to be tested.

[0078] Based on the same inventive concept, the embodiment of the present application also provides an inertia and damping coefficient detection system for power electronic equipment for implementing the inertia and damping coefficient detection method for power electronic equipment involved above. The implementation scheme for solving the problem provided by the system is similar to the implementation scheme recorded in the above method, so the specific limitations in the embodiments of the inertia and damping coefficient detection system for power electronic equipment provided below can refer to the limitations of the inertia and damping coefficient detection method for power electronic equipment above, and will not be repeated here.

[0079] In an exemplary embodiment, Figure 2 As shown, a system for detecting inertia and damping coefficient of power electronic equipment is provided, comprising: a detection device and an inertia and damping coefficient detection device. The detection device is connected to the power electronic equipment to be tested. The inertia and damping coefficient detection device is connected to the detection device. The detection device is mainly used to obtain the inertia and damping coefficient of the power electronic equipment to be tested. and AC current The inertia and damping coefficient detection device is mainly used to detect the AC voltage of the power electronic equipment to be tested. and AC current , determine the coefficient of the power electronic equipment to be tested and the damping coefficient .

[0080] As an optional implementation, the inertia and damping coefficient detection device provided above in the present application includes:

[0081] The frequency and change rate calculation module is connected to the detection device and is used to determine the frequency and the frequency change rate based on the AC voltage.

[0082] For example, Figure 3 The frequency and change rate calculation module shown includes: a phase detector, a low-pass filter and a voltage-controlled oscillator. Based on this structural setting, its working process is as follows:

[0083] The AC voltage The input phase detector obtains the feedback signal The phase difference signal . Phase difference signal The smoothed error signal is obtained after being smoothed by a low-pass filter The smoothed error signal The feedback signal is sent to the voltage controlled oscillator to adjust the generated feedback signal. , reducing the feedback signal With the real AC voltage signal Through this process, the voltage-controlled oscillator eventually generates a voltage that is equal to the AC voltage. Highly similar feedback signal , and output the generated feedback signal Frequency and frequency change rate .

[0084] The active power calculation module is connected to the detection device and is used to determine the active power based on the AC voltage and the AC current.

[0085] For example, Figure 4 The active power calculation module shown includes: a phase-locked loop. Based on this structural setting, its working process is as follows:

[0086] The AC voltage and the phase-locked loop PLL locks out Phase angle of rotating coordinate system conduct Convert to obtain AC voltage Shaft voltage component and Shaft voltage component ; The alternating current The phase angle of the rotating coordinate system locked by the phase-locked loop PLL conduct Convert to obtain AC current Shaft current component and Shaft current component ; Based on AC voltage Shaft voltage component and Shaft voltage component , AC current Shaft current component and Shaft current component Perform algebraic operations to obtain the active power , active power The calculation formula is as follows:

[0087] .

[0088] in, is the active power, For AC voltage The shaft voltage component, For AC voltage The shaft voltage component, For alternating current The shaft current component, For alternating current Shaft current component.

[0089] A disturbance monitoring module, connected to the frequency and change rate calculation module, the detection device or the active power calculation module, and used to generate a disturbance signal based on frequency, active power, AC voltage or AC current;

[0090] For example, Figure 5 The disturbance monitoring module shown gives the working process of generating disturbance signals according to the frequency, as follows:

[0091] Through the delay phase The frequency Delay one cycle, and make a difference between the original frequency and the delayed frequency, and compare the absolute value of the difference with the threshold Compare, if the absolute value of the difference is less than the threshold The output disturbance signal 0 if the absolute value of the difference is greater than the threshold The output disturbance signal is 1.

[0092] The data recording module is connected to the frequency and change rate calculation module, the active power calculation module and the disturbance monitoring module, and is used to obtain the frequency vector, the frequency change rate vector and the active power vector during the disturbance period based on the frequency, the frequency change rate and the active power when the disturbance signal is 1.

[0093] For example, Figure 6 The data recording module shown records the information during the disturbance, and its working process is as follows:

[0094] When the disturbance monitoring module outputs a disturbance signal When it is 0, the data recording module outputs a zero vector; when the output disturbance signal When it is 1, the frequency output by the frequency and change rate calculation module and the active power calculation module , frequency change rate and active power , recorded as the frequency vector in the disturbance , frequency change rate vector and the active power vector .like Figure 8 As shown in Figure 1, the module records the normalized active power and frequency after the disturbance occurs.

[0095] The inertia and damping coefficient calculation module is connected to the data recording module and is used to determine the inertia coefficient and damping coefficient of the power electronic equipment to be tested based on the frequency vector, the frequency change rate vector and the active power vector.

[0096] For example, Figure 7 The inertia and damping coefficient calculation module shown mainly uses the least square method for regression calculation to obtain the inertia coefficient and damping coefficient of the power electronic equipment to be tested. The working process is as follows:

[0097] In practical applications, the frequency vector recorded by the data recording module is , frequency change rate vector and the active power vector Perform per-unit processing to obtain the per-unit frequency vector , the normalized frequency rate of change vector and the normalized active power vector The reference value of the power per unit value can be set in advance or obtained from its normal frequency operation process; the reference value of the frequency per unit value can be set in advance or obtained from its normal operation process; it is worth noting that if the real value is not the per unit value, this method can calculate the actual inertia and damping of the measured power electronic equipment. and (Each portion is A vector of is the dimension of the vector) and then normalize the deviation to obtain the normalized frequency deviation vector .

[0098] The inertia and damping model between the independent variable and the dependent variable is established. The inertia and damping model is expressed as:

[0099] .

[0100] in, is the actual active power after normalization, is the normalized rated active power, is the regression coefficient of frequency deviation, is the normalized frequency deviation, is the regression coefficient of the frequency change rate, is the normalized frequency change rate, is the error term.

[0101] Construct the independent variables into an independent variable matrix , the independent variable matrix The form is as follows:

[0102] .

[0103] Among them, the first column constant 1 is the standard value of the active power set by the calculation intercept , the second column is the frequency deviation Data, the third column is the frequency change rate data, is the number of data points recorded.

[0104] The least squares method is used to minimize the sum of squared errors between the observed and predicted values ​​to find the best fitting regression coefficients. The matrix operation is as follows:

[0105] .

[0106] in, is the regression coefficient of the rated active power , the regression coefficient of frequency deviation and the regression coefficient of the frequency change rate The regression coefficient vector composed of is the vector composed of normalized active power.

[0107] The regression coefficient vector can be calculated through matrix operations , that is, the regression coefficient of the rated active power , the regression coefficient of frequency deviation and the regression coefficient of the frequency change rate The regression coefficient vector is composed of Equal to the inertia coefficient of the measured power electronic equipment 2 times; the regression coefficient of frequency deviation Numerically equal to the damping coefficient of the measured power electronic equipment .

[0108] In practical applications, the coefficient of determination It is used to quantify the goodness of fit of the established inertia and damping model to the output of power electronic equipment. It characterizes the degree to which the inertia and damping model explains the observed data. The specific solution process is as follows:

[0109] First, solve the total sum of squares of the dependent variable. The specific calculation formula for the total sum of squares is as follows:

[0110] .

[0111] in, is the total sum of squares of the dependent variable, is the actual value of the dependent variable, is the mean of the dependent variable, is the number of data points recorded.

[0112] Second, solve the residual sum of squares between the observed value and the model predicted value. The specific public statement of the residual sum of squares is as follows:

[0113] .

[0114] in, is the residual sum of squares between the observed value and the model predicted value, is the actual dependent variable, is the dependent variable to be predicted, is the number of data points recorded.

[0115] Third, solve the coefficients , coefficient of determination The specific formula is as follows:

[0116] .

[0117] Coefficient of determination It is used to judge the goodness of fit of the inertia and damping models, that is, the model's ability to explain the data. Specifically, when The closer the value is to 1, the better the model fits the data, the stronger the linear relationship between the frequency change rate and the deviation and the active power, and the more credible the obtained inertia and damping coefficient. If the value is lower than a certain value (for example, 0.6), it is considered that the inertia and damping models are difficult to accurately reflect the dynamic characteristics of the actual measured power electronic equipment.

[0118] In another exemplary embodiment of the present application, in a simulation model, the inertia coefficient, damping coefficient and determination coefficient are calculated by an inertia and damping coefficient detection system for power electronic equipment provided by the present application, and the calculation results are as follows: Fig. 9 Shown: Inertia coefficient The simulation result is 9.79, and the error between it and the given value 10 is less than 3%. Therefore, the method provided in this application can effectively measure the inertia coefficient of the power electronic equipment under test. ; Damping coefficient The simulation result is 38.5, and the error between it and the given value of 40 is less than 3%. Therefore, the method provided in this application can effectively measure the damping coefficient of the power electronic equipment under test. Coefficient of determination The simulation result is 0.95, indicating that the power electronic equipment under test has obvious inertia and damping characteristics, and the measured inertia and damping coefficient results are accurate.

[0119] The implementation method disclosed in the present application is simple, has low testing cost and high economic benefits; it calculates the inertia and damping coefficient of power electronic equipment during grid-connected operation, breaks through the problem of traditional methods relying on off-grid testing, and realizes real-time online evaluation of the grid support capability of power electronic equipment; and fully utilizes small disturbances in grid operation for detection without introducing additional disturbances, thereby ensuring the operational stability of the grid and power electronic equipment.

[0120] In an exemplary embodiment, a computer device is provided. The computer device may be a server or a terminal. The internal structure diagram thereof may be as follows: Fig.10 As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. Among them, the processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store inertia and damping coefficient detection data of power electronic equipment. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a method for detecting inertia and damping coefficient of power electronic equipment is implemented.

[0121] Those skilled in the art will understand that Fig.10 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components. In an exemplary embodiment, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0122] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0123] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM may be in various forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM).

[0124] The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. The non-relational database may include a distributed database based on blockchain, etc., but is not limited thereto. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but is not limited thereto.

[0125] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0126] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A method for detecting inertia and damping coefficient of power electronic equipment, characterized in that: The inertia and damping coefficient detection method of the power electronic equipment includes: Obtain the AC voltage and AC current of the power electronic equipment to be tested in real time; determining a frequency and a rate of change of frequency based on the AC voltage; determining active power based on the AC voltage and the AC current; generating a disturbance signal based on the frequency, the active power, the AC voltage or the AC current; When the disturbance signal is 0, no processing is performed; When the disturbance signal is 1, based on the frequency, the frequency change rate and the active power, a frequency vector, a frequency change rate vector and an active power vector during the disturbance are obtained; Determining the inertia coefficient and damping coefficient of the power electronic equipment to be tested based on the frequency vector, the frequency change rate vector and the active power vector; The determining of the inertia coefficient and the damping coefficient of the power electronic equipment to be tested based on the frequency vector, the frequency change rate vector and the active power vector comprises: The frequency vector, the frequency change rate vector and the active power vector are normalized to obtain a normalized frequency vector, a normalized frequency change rate vector and a normalized active power vector; Perform deviation normalization processing on the per-unit frequency vector to obtain a per-unit frequency deviation vector; The normalized frequency deviation vector, the normalized frequency change rate vector and the normalized active power vector are subjected to regression calculation by the least square method to obtain the inertia coefficient and damping coefficient of the power electronic equipment to be tested.

2. The method for detecting inertia and damping coefficient of power electronic equipment according to claim 1, characterized in that: The method for detecting inertia and damping coefficient of the power electronic equipment further includes: Based on the frequency vector, the frequency change rate vector and the active power vector, a determination coefficient of the power electronic equipment to be tested is determined, and the determination coefficient is used to judge the validity of the inertia coefficient and the damping coefficient.

3. The method for detecting inertia and damping coefficient of power electronic equipment according to claim 1, characterized in that: The determining of the frequency and the frequency change rate based on the AC voltage of the power electronic equipment to be tested comprises: Obtaining a phase difference signal based on the AC voltage; Performing filtering and smoothing processing on the phase difference signal to obtain an error signal; Performing oscillation adjustment on the error signal to generate a feedback signal; The frequency and the rate of change of frequency are determined based on the feedback signal.

4. The method for detecting inertia and damping coefficient of power electronic equipment according to claim 1, characterized in that: The determining of active power based on the AC voltage of the power electronic equipment to be tested and the AC current of the power electronic equipment to be tested comprises: Using a phase-locked loop to obtain a phase angle based on the AC voltage of the power electronic equipment to be tested; Perform coordinate transformation on the AC voltage and the phase angle of the power electronic equipment to be tested to obtain the AC voltage of the power electronic equipment to be tested. Shaft voltage components and Shaft voltage component; The AC current of the power electronic equipment to be tested and the phase angle are transformed to obtain the AC current of the power electronic equipment to be tested. Shaft current components and Shaft current component; Based on the AC voltage of the power electronic equipment to be tested Shaft voltage components and Shaft voltage component and AC current of the power electronic equipment under test Shaft current components and Shaft current components, determine the active power.

5. The method for detecting inertia and damping coefficient of power electronic equipment according to claim 4, characterized in that: The coordinate transformation is: the AC voltage and AC current of the power electronic equipment to be tested are transformed from the three-phase static Coordinate system transformation to rotation Coordinate system.

6. The method for detecting inertia and damping coefficient of power electronic equipment according to claim 1, characterized in that: The generating a disturbance signal based on the frequency, the active power, the AC voltage or the AC current comprises: Determine the difference between the current frequency, active power, AC voltage or AC current and the previous frequency, active power, AC voltage or AC current; Determine whether the absolute value of the difference is less than a set threshold value, and obtain a determination result; When the judgment result is yes, the disturbance signal is 0; When the judgment result is no, the disturbance signal is 1.

7. A system for detecting inertia and damping coefficient of power electronic equipment, characterized in that: The inertia and damping coefficient detection system of the power electronic equipment comprises: A detection device, connected to the power electronic equipment to be tested, for obtaining the AC voltage and AC current of the power electronic equipment to be tested; An inertia and damping coefficient detection device is connected to the detection device, and implements the inertia and damping coefficient detection method of the power electronic equipment as described in any one of claims 1 to 6 based on the AC voltage and AC current of the power electronic equipment to be tested, so as to obtain the inertia coefficient and damping coefficient of the power electronic equipment to be tested.

8. The inertia and damping coefficient detection system for power electronic equipment according to claim 7, characterized in that: The inertia and damping coefficient detection device comprises: A frequency and change rate calculation module, connected to the detection device, for determining the frequency and the frequency change rate based on the AC voltage; an active power calculation module, connected to the detection device, and used to determine the active power based on the AC voltage and the AC current; A disturbance monitoring module, connected to the frequency and change rate calculation module, the detection device or the active power calculation module, and used to generate a disturbance signal based on the frequency, the active power, the AC voltage or the AC current; A data recording module, connected to the frequency and change rate calculation module, the active power calculation module and the disturbance monitoring module, for obtaining a frequency vector, a frequency change rate vector and an active power vector during a disturbance based on the frequency, the frequency change rate and the active power when the disturbance signal is 1; The inertia and damping coefficient calculation module is connected to the data recording module, and is used to determine the inertia coefficient and damping coefficient of the power electronic equipment to be tested based on the frequency vector, the frequency change rate vector and the active power vector.

9. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the inertia and damping coefficient detection method for power electronic equipment according to any one of claims 1 to 6.

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