A new energy unit electromechanical transient simulation model parameter checking method

Abstract

The present application relates to the field of power system automation, and discloses a new energy unit electromechanical transient simulation model parameter checking method, which comprises the following steps: reading field measurement or hardware-in-the-loop simulation test fault ride-through data of the new energy unit, calculating the fundamental positive sequence components of voltage, active power, reactive power and phase voltage effective value, and performing filtering processing and fault interval division; extracting initial state data and fault type information, and setting the initial state of electromechanical transient simulation to obtain fault ride-through test data of electromechanical simulation; calculating the deviation of multiple data of measurement or hardware-in-the-loop simulation and electromechanical transient simulation; if the deviation meets the requirements, the electric transient model meets the requirements, otherwise the electromechanical transient model does not meet the requirements. The method can complete the electromechanical transient simulation model checking of the new energy unit based on the measured, hardware-in-the-loop simulation test fault ride-through data, and can complete the model parameter checking in batches, quickly, accurately and automatically.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power system automation, in particular to a new energy unit electromechanical transient simulation model parameter checking method. BACKGROUND

[0002] With the construction of new power systems and large-scale new energy grid connection, in order to calculate and analyze the stability of the power system, it is urgent to carry out electromechanical transient simulation of new energy units; and the "Guidelines for Safety and Stability of Power Systems", "Guidelines for Power Grid Operation", "Technical Regulations for Access of Wind Power Plants to Power Systems Part 1 - Land-based Wind Power", "Technical Regulations for Access of Photovoltaic Power Stations to Power Systems" require that the electromechanical transient modeling of new energy units be carried out before and after the grid connection, and the measured modeling report and model verification data that meet the simulation calculation requirements of the power grid dispatching agency be submitted.

[0003] The existing electromechanical transient of new energy units is checked manually and point by point, or most existing institutions only use hardware-in-the-loop simulation test fault ride-through data for checking, and few use field measured fault ride-through data for checking; the existing checking method is low in efficiency and accuracy.

[0004] Therefore, there is an urgent need for a fast, accurate and automatic new energy unit electromechanical transient simulation model parameter checking method. SUMMARY

[0005] To solve the problems of the prior art, the present application provides a new energy unit electromechanical transient simulation model parameter checking method, which can quickly, accurately and automatically check the new energy unit electromechanical transient simulation model parameters, and is easy to popularize and apply.

[0006] The technical scheme adopted by the present application is:

[0007] A new energy unit electromechanical transient simulation model parameter checking method, the new energy unit electromechanical transient simulation model parameter checking method comprising the following steps:

[0008] Step 1, data reading:

[0009] Read the fault ride-through data of the new energy unit field measurement or hardware-in-the-loop simulation test; the fault ride-through data includes the voltage and current instantaneous value data of the 35kV side of the box-type transformer or the machine end of the new energy unit; the full-cycle Fourier algorithm is used to calculate the phase voltage effective value, the voltage of the fundamental positive sequence component, the active power, the reactive power, the active current and the reactive current of the 35kV side or the machine end of the new energy unit;

[0010] Step 2, data processing:

[0011] The fundamental positive sequence component active current is filtered; in the filtering process, the Kalman filtering algorithm is used to filter the fundamental positive sequence component active current; the fundamental positive sequence component voltage, active power, reactive power, active current and reactive current data are divided into pre-fault, fault period, post-fault transient and steady state intervals;

[0012] Step 3, parameter calculation:

[0013] Substitute the electromechanical transient simulation model, set the initial voltage U0, active power P0 and reactive power Q0, and perform power flow calculation; set the fault type, fault duration t last , fault impedance x1 or x2; simulate fault ride-through in electromechanical transient simulation software to obtain electromechanical transient simulation fault ride-through test data;

[0014] Step 4, power flow calculation:

[0015] Substitute the electromechanical transient simulation model, set the initial voltage U0, active power P0 and reactive power Q0, and perform power flow calculation; set the fault type, fault duration t last , fault impedance x1 or x2; simulate fault ride-through in electromechanical transient simulation software to obtain electromechanical transient simulation fault ride-through test data;

[0016] Step 5, deviation calculation and correction:

[0017] Based on the fault interval division, the fundamental positive sequence voltage pre-fault, fault period and post-fault steady state period deviation of the measured or hardware-in-the-loop simulation fault ride-through test data and the electromechanical transient simulation fault ride-through test data is calculated;

[0018] If the deviation meets the requirements, proceed to the next step;

[0019] Otherwise, correct the fault impedance x1 or x2 and re-perform electromechanical transient simulation;

[0020] Step 6, final deviation analysis:

[0021] Based on the fault interval division, the fundamental positive sequence active power, reactive power, active current and reactive current deviation of the measured or hardware-in-the-loop simulation and electromechanical transient simulation fault ride-through test data is calculated, and the deviation is divided into pre-fault, fault period and post-fault transient and steady state period;

[0022] If all the deviations meet the requirements, it means that the new energy unit electromechanical transient simulation model meets the requirements; otherwise, it means that the new energy unit electromechanical transient simulation model does not meet the requirements.

[0023] Further, in step 1, the fault ride-through data refers to:

[0024] Three-phase phase voltage effective value drops to 0%U n , 20%U n , 35%U n , 50%U n , 75%U n , only two-phase line voltage effective value drops to 0%U n , 20%U n , 35%U n , 50%U n , 75%U n ; three-phase phase voltage effective value rises to 130%U n , 125%U n , 120%U n , 115%U n , only two-phase line voltage effective value rises to 130%U n , 125%U n , 120%U n , 115%U n .

[0025] Further, in step 2, the interval division of data is specifically:

[0026] Based on the fundamental positive sequence voltage, the three stages of before fault, during fault and after fault are divided, which are specifically:

[0027] ① When the voltage amplitude is less than 0.9U n or greater than 1.1U n , the moment before 20ms is before fault;

[0028] ② From the moment when the voltage amplitude is less than 0.9U n or greater than 1.1U n to the moment when the voltage amplitude is greater than 0.9U n or less than 1.1U n , within 20ms is during fault;

[0029] ④ From the moment when the voltage amplitude is greater than 0.9U n or less than 1.1U n , within 20ms is after fault;

[0030] Based on the fundamental positive sequence active current, the steady-state and transient interval of fault is divided, and the specific method is:

[0031] ① From the moment when the voltage amplitude is less than 0.9U n or greater than 1.1U n , within 20ms before fault is the steady-state interval before fault;

[0032] ② During the fault, the moment when the fundamental positive sequence active current enters the steady state value after 20 ms is the transient interval during the fault; the moment when the fundamental positive sequence active current enters the steady state value after 20 ms to the moment 20 ms before the voltage amplitude is greater than 0.9U n or less than 1.1U n is the steady state interval during the fault;

[0033] ③ After the fault, the moment 20 ms before the voltage amplitude is greater than 0.9U n or less than 1.1U n to the moment when the fundamental positive sequence active current enters the steady state value after 20 ms is the transient interval after the fault; the moment when the fundamental positive sequence active current enters the steady state value after 20 ms to within 2s is the steady state interval after the fault.

[0034] Further, in step 3, the specific process of fault type judgment is as follows:

[0035] (1) The effective value per unit of three-phase voltage U a , U b , U c compared with the per unit value of fundamental positive sequence voltage U T ;

[0036] (2) If the effective value per unit of three-phase voltage U a , U b , U c compared with the per unit value of fundamental positive sequence voltage U T is within 1%U n , then the fault type is symmetric fault; that is, |U a -U T |<1%U n , and |U b -U T |<1%U n , and |U c -U T |<1%U n , then it is a symmetric fault;

[0037] (3) If the effective value per unit of three-phase voltage U a , U b , U c compared with the per unit value of fundamental positive sequence voltage U T is not within 1%U n , then the fault type is asymmetric fault; that is, |U a -U T |≥1%U n , or |U b -U T |≥1%U n , or |U c-U T |≥1%U n , then it is an unsymmetrical fault.

[0038] Further, in step 3, the fault impedance x1 is the fault impedance when the fault is symmetrical, and the fault impedance x2 is the fault impedance when the fault is unsymmetrical; the specific calculation method is as follows:

[0039] The fault impedance x1 is:

[0040]

[0041] In the formula, U T is the fundamental positive sequence voltage; x 系 is the impedance value of the system in the electromechanical simulation; U0 is the reference voltage of the system, which is the voltage value of the system in the fault-free state.

[0042] The fault point voltage U T is:

[0043]

[0044] According to the above formula, the fault impedance x2 is calculated as:

[0045]

[0046] Further, in steps 5 and 6, the deviation of each interval is the maximum value of the average deviation, the average absolute deviation, the maximum deviation, and the weighted average absolute deviation as follows:

[0047] The deviation values of the steady state period and the transient interval are relatively consistent; each type of power parameter: fundamental positive sequence voltage, active power, reactive power, active current, and reactive current, shows the same deviation value before, during, and after the fault; in terms of numerical value, the main deviation is between 0.02 fundamental voltage and 0.10 active and reactive power and current;

[0048] The average absolute deviation and the average deviation have similar trends, and the deviation values of the steady state and the transient interval remain consistent; the deviation values of each type of parameter are the same as the average deviation, which is 0.02 to 0.10;

[0049] The maximum deviation shows the same maximum deviation value in the steady state period and the transient interval; the maximum deviation of the fundamental positive sequence voltage is 0.05, while the maximum deviation of other parameters: active power, reactive power, active current, and reactive current, is 0.15, showing similarity;

[0050] The weighted average absolute deviation of all power parameters is 0.15, indicating that the influence of the deviation of each parameter is relatively consistent in the weighted calculation.

[0051] Compared with the prior art, the new energy unit electromechanical transient simulation model parameter checking method has the following beneficial effects:

[0052] (1) The new energy unit electromechanical transient simulation model parameter checking method can realize batch, rapid, accurate and automatic checking of the electromechanical transient simulation model of the new energy unit; the checking work can be carried out once to check all the fault ride-through data, the checking work time is shortened from 3 days to 1 hour, the checking accuracy meets the existing national standard requirements, and the results are output to a word document, thereby improving the work efficiency.

[0053] (2) The new energy unit electromechanical transient simulation model parameter checking method is based on the division of the transient and steady state intervals before, during and after the fault based on the fundamental positive sequence voltage and the fundamental positive sequence active current.

[0054] (3) The new energy unit electromechanical transient simulation model parameter checking method proposes a criterion method for symmetrical and asymmetrical faults by using the difference between the per-phase voltage of the fault interval and the fundamental positive sequence voltage.

[0055] (4) The new energy unit electromechanical transient simulation model parameter checking method is not affected by the voltage drop depth or the lifting height, the active power size. BRIEF DESCRIPTION OF DRAWINGS

[0056] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained according to these drawings without creative labor for those skilled in the art.

[0057] Among them:

[0058] Figure 1 is the flow chart of the new energy unit electromechanical transient simulation model parameter checking method of the present application;

[0059] Figure 2 is the comparative diagram of the large power three-phase voltage symmetrical drop to 20%U n of the new energy unit and the electromechanical transient simulation model of the present application;

[0060] Figure 3 is the comparative diagram of the large power three-phase voltage asymmetrical drop to 35%U n of the new energy unit and the electromechanical transient simulation model of the present application;

[0061] Figure 4 is the comparative diagram of the large power three-phase voltage symmetrical lifting to 130%U n of the new energy unit and the electromechanical transient simulation model of the present application. Detailed Implementation

[0062] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] To address the issues of low efficiency and accuracy in existing verification methods for electromechanical transients of new energy generating units, which rely on manual, point-by-point verification or, in most cases, only hardware-in-the-loop simulation testing of fault ride-through data, this embodiment provides a method for verifying the parameters of an electromechanical transient simulation model for new energy generating units.

[0064] This method for verifying the parameters of the electromechanical transient simulation model of new energy generating units can quickly, accurately, and automatically verify the parameters of the electromechanical transient simulation model of new energy generating units, and is easy to promote and apply; for example Figure 1 As shown, the parameter verification method for the electromechanical transient simulation model of this new energy unit specifically includes the following steps:

[0065] Step 1, Data Reading:

[0066] Read fault ride-through data from on-site measurements or hardware-in-the-loop simulation tests of new energy power units.

[0067] Fault ride-through data includes instantaneous voltage and current values ​​on the 35kV side of the box-type transformer or at the generator terminal of the new energy unit.

[0068] Specifically, the following parameters are calculated using the full-cycle Fourier algorithm:

[0069] (1) Effective value of phase voltage on the 35kV side or at the generator terminal of a new energy unit

[0070] (2) Voltage, active power, reactive power, active current, and reactive current of the fundamental positive sequence component.

[0071] Furthermore, fault ride-through data indicates that the effective value of the three-phase phase voltage drops to 0%U. n 20% U n 35% U n 50% U n 75% U n Only the effective value of the line voltage of two phases dropped to 0%U n 20% U n 35% U n 50% U n 75% U n The effective value of the three-phase phase voltage increased to 130%U.n , 125%U n , 120%U n , 115%U n , only two-phase line voltage effective value rises to 130%U n , 125%U n , 120%U n , 115%U n .

[0072] Step 2, data processing:

[0073] The active current of the fundamental positive sequence component is filtered; in the filtering process, the Kalman filtering algorithm is used to filter the active current of the fundamental positive sequence component. The voltage, active power, reactive power, active current and reactive current data of the fundamental positive sequence component are divided into pre-fault, fault period, post-fault transient and steady state intervals.

[0074] Further, the interval division of data is specifically:

[0075] (1) Based on the fundamental positive sequence voltage, the pre-fault, fault period and post-fault three stages are divided, specifically:

[0076] ① When the voltage amplitude is less than 0.9U n or greater than 1.1U n , the 20ms before the moment is pre-fault;

[0077] ② From the 20ms before the moment when the voltage amplitude is less than 0.9U n or greater than 1.1U n to the 20ms before the moment when the voltage amplitude is greater than 0.9U n or less than 1.1U n , it is the fault period;

[0078] ③ From the 20ms before the moment when the voltage amplitude is greater than 0.9U n or less than 1.1U n , it is post-fault.

[0079] (2) Based on the fundamental positive sequence active current, the steady state and transient state intervals of the fault are divided, and the specific method is:

[0080] ① From the 20ms before the moment when the voltage amplitude is less than 0.9U n or greater than 1.1U n to 1s before the fault, it is the pre-fault steady state interval;

[0081] ② During the fault period, 20ms after the fundamental positive sequence active current enters the steady state value after the voltage drop or voltage rise is the transient interval during the fault period; from the 20ms after the fundamental positive sequence active current enters the steady state value, to the moment when the voltage amplitude is greater than 0.9Un or less than 1.1U n The 20ms before the moment is the steady state interval during the fault.

[0082] ③ After the fault, the voltage amplitude is greater than 0.9U n or less than 1.1U n The 20ms before the moment to the steady state value of the fundamental positive sequence active current after 20ms after the moment is the transient interval after the fault; the 2s after the steady state value of the fundamental positive sequence active current is the steady state interval after the fault.

[0083] Step 3, parameter calculation:

[0084] Calculate the initial voltage U0, active power P0, reactive power Q0, fault fundamental positive sequence voltage U T ; Calculate the fault duration t last , and then determine the fault type. Calculate the simulation setting fault impedance x1 or x2.

[0085] The specific process of fault type determination is as follows:

[0086] (1) The effective value per unit of three-phase voltage U a , U b , U c during the steady state interval during the fault compared with the per unit value of the fundamental positive sequence voltage U T ;

[0087] (2) If the difference between the effective value per unit of three-phase voltage U a , U b , U c and the per unit value of the fundamental positive sequence voltage U T is within 1%U n , then the fault type is symmetric fault;

[0088] That is, |U a -U T |<1%U n , and |U b -U T |<1%U n , and |U c -U T |<1%U n , then it is a symmetric fault;

[0089] (3) If the difference between the effective value per unit of three-phase voltage U a , U b , U c and the per unit value of the fundamental positive sequence voltage U T is not within 1%U n , then the fault type is asymmetric fault;

[0090] That is |U a -U T |≥1%U n , or |U b -U T |≥1%U n , or |U c -U T |≥1%U n If so, it is an asymmetric fault.

[0091] Furthermore, in this embodiment, the fault refers to a two-phase voltage fault.

[0092] Fault impedance x1 is the fault impedance for a symmetrical fault, and fault impedance x2 is the fault impedance for an asymmetrical fault; the specific calculation method is as follows:

[0093] (1) The fault impedance x1 is:

[0094]

[0095] In the formula, U T The fundamental positive sequence voltage; x 系 In electromechanical simulation, U0 represents the system's impedance value; U0 is the system's reference voltage, which is the voltage value of the system under fault-free conditions.

[0096] (2) The fault impedance x2 is:

[0097] Fault point voltage U T for:

[0098]

[0099] Based on the above formula, the fault impedance x2 is calculated as follows:

[0100]

[0101] Step 4, Power Flow Calculation:

[0102] Substitute the values ​​into the electromechanical transient simulation model, set the initial voltage U0, active power P0, and reactive power Q0, and perform power flow calculations; set the fault type and fault duration t. last Fault impedance x1 or x2; simulate fault ride-through in electromechanical transient simulation software to obtain fault ride-through test data of electromechanical transient simulation.

[0103] Step 5, Deviation Calculation and Correction:

[0104] Based on the fault interval division, the deviation of the fundamental positive sequence voltage before, during, and after the fault steady state of the fault ride-through test data obtained by actual measurement or hardware-in-the-loop simulation and the fault ride-through test data obtained by electromechanical transient simulation is calculated.

[0105] If the deviation meets the requirements, the next step is performed;

[0106] Otherwise, the fault impedance x1 or x2 is corrected and the electromechanical transient simulation is restarted.

[0107] Step 6, final deviation analysis:

[0108] Based on the fault interval division, the deviations of the fundamental positive sequence active power, reactive power, active current and reactive current of the fault ride-through test data of the measured or hardware-in-the-loop simulation and the electromechanical transient simulation are calculated, which are divided into pre-fault, fault period and post-fault transient and steady-state periods.

[0109] If all the deviations meet the requirements, it means that the electromechanical transient simulation model of the new energy unit meets the requirements; otherwise, it means that the electromechanical transient simulation model of the new energy unit does not meet the requirements.

[0110] In steps 5 and 6, the deviations of each interval are the average deviation, the maximum absolute deviation, the maximum deviation and the maximum weighted average absolute deviation as shown in the following table:

[0111]

[0112]

[0113] Based on the above steps, the new energy unit electromechanical transient simulation model parameter checking method can realize batch, fast, accurate and automatic checking of the electromechanical transient simulation model of the new energy unit; the checking work can be carried out for all fault ride-through data at one time, and the checking results are automatically output to the word document.

[0114] Further, in order to verify the accuracy of the new energy unit electromechanical transient simulation model parameter checking method, the following actual verification is carried out:

[0115] Actual verification 1:

[0116] The electromechanical transient simulation model parameters of 12 250kW photovoltaic arrays of a certain photovoltaic power station are checked, as shown in the following table, taking the case of a large power three-phase voltage symmetrical drop to 20%U n Figure 2

[0117] First, read the voltage and current instantaneous value data of the 35kV side, calculate the effective value of the phase voltage, the voltage, active power, reactive power, active current and reactive current of the fundamental positive sequence component by using the full cycle Fourier algorithm;

[0118] The Kalman filter algorithm is used to filter the fundamental positive sequence active current, and the initial voltage U0 is calculated as 1.041U n ​​, active power P0 is 2.268 MW, reactive power Q0 is -0.159 MVar, fault fundamental positive sequence voltage U T is 0.3137U n , fault duration t last 627 ms;

[0119] The fault type is judged to be a three-phase symmetric fault, the system impedance is 0.0548, the fault impedance x1 is calculated to be 0.0238, and the photovoltaic array electromechanical transient simulation model is substituted;

[0120] Based on the fundamental positive sequence voltage and active current, the data interval is divided, and the fundamental positive sequence active power, reactive power, active current, and reactive current deviation results of the fault ride-through test data and the simulation low voltage ride-through test data are as shown in the following table:

[0121]

[0122] Each item meets the requirements, and the new energy unit electromechanical transient simulation model parameters meet the requirements.

[0123] Actual verification 2:

[0124] The electromechanical transient simulation model parameters of 12 250kW photovoltaic arrays of a certain photovoltaic power station are checked, as shown in Figure 3 , taking the case of a large power three-phase voltage asymmetric drop to 35%U n as an example.

[0125] First, read the voltage and current instantaneous value data of the 35kV side, and use the full cycle Fourier algorithm to calculate the phase voltage effective value, fundamental positive sequence component voltage, active power, reactive power, active current, and reactive current;

[0126] The Kalman filter algorithm is used to filter the fundamental positive sequence active current, the initial voltage U0 is calculated to be 1.04U n , the active power P0 is 2.268 MW, the reactive power Q0 is -0.1615 MVar, the fault fundamental positive sequence voltage U T is 0.6498U n , the fault duration t last is 926 ms;

[0127] The fault type is judged to be an asymmetric fault, the system impedance is 0.0548, the fault impedance x2 is calculated to be 0.0234, and the photovoltaic array electromechanical transient simulation model is substituted;

[0128] The deviation results of the fundamental positive sequence active power, reactive power, active current and reactive current of the fault ride-through test data and the simulation low voltage ride-through test data based on the fundamental positive sequence voltage and active current are shown in the following table:

[0129]

[0130] The deviations meet the requirements, and the electromechanical transient simulation model parameters of the new energy unit meet the requirements.

[0131] Actual verification 3:

[0132] The electromechanical transient simulation model parameters of 12 250kW photovoltaic arrays of a certain photovoltaic power station are checked, as shown in the following table, taking the case of symmetric lifting of the high-power three-phase voltage to 130%U n Figure 4

[0133] First, read the voltage and current instantaneous value data of the 35kV side, and use the full cycle Fourier algorithm to calculate the effective value of the phase voltage, the fundamental positive sequence component voltage, active power, reactive power, active current and reactive current;

[0134] The initial voltage U0 is 1.039U0, the active power P0 is 2.264MW, the reactive power Q0 is-0.1615MVar, the fault fundamental positive sequence voltage U T is 1.289Un, and the fault duration t last is 505ms, using Kalman filter algorithm for filtering processing of the fundamental positive sequence active current;

[0135] The fault type is judged to be symmetric fault, the system impedance is 0.0548, the fault impedance x1 is-0.2809, and the photovoltaic array electromechanical transient simulation model is calculated;

[0136] The deviation results of the fundamental positive sequence active power, reactive power, active current and reactive current of the fault ride-through test data and the simulation low voltage ride-through test data based on the fundamental positive sequence voltage and active current are shown in the following table:

[0137]

[0138]

[0139] The deviations meet the requirements, and the electromechanical transient simulation model parameters of the new energy unit meet the requirements.

[0140] ​​In summary, the parameter checking method of the electromechanical transient simulation model of the new energy unit can check the electromechanical transient simulation model of the new energy unit based on measured, hardware-in-the-loop simulation test fault ride-through data, and can batch, quickly, accurately and automatically complete the model parameter checking; based on the division of the transient and steady state intervals before, during and after the fault based on the fundamental positive sequence voltage and the fundamental positive sequence active current; using the difference between the per-phase voltage and the fundamental positive sequence voltage of the fault interval as the criterion for symmetric and asymmetric faults; the checking result is not affected by the voltage drop depth or the lifting height, the active power size.

[0141] It will be obvious to a person skilled in the art that the application is not limited to the details of the above-described exemplary embodiments, but that the application can be implemented in other concrete forms without departing from the spirit or essential characteristics of the application. The embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the above description, and it is intended to encompass all changes and modifications that fall within the meaning and scope of the claims. Any reference signs in the claims should not be construed as limiting the claims concerned.

Claims

1. A method for checking parameters of a mechanical-electrical transient simulation model of a new energy unit, characterized in that, The new energy unit electromechanical transient simulation model parameter checking method comprises the following steps: Step 1, data reading: Read the fault ride-through data of the new energy unit field measurement or hardware-in-the-loop simulation test; the fault ride-through data includes the voltage and current instantaneous value data of the 35kV side of the box-type transformer or the new energy unit terminal; the full-cycle Fourier algorithm is used to calculate the phase voltage effective value, the voltage of the fundamental positive sequence component, the active power, the reactive power, the active current and the reactive current of the 35kV side or the new energy unit terminal; Step 2, data processing: The active current of the fundamental positive sequence component is filtered; in the filtering process, the Kalman filtering algorithm is used to filter the active current of the fundamental positive sequence component; the voltage, active power, reactive power, active current and reactive current data of the fundamental positive sequence component are divided into pre-fault, fault period and post-fault transient and steady state intervals; Step 3, parameter calculation: Calculate initial voltage , active power , reactive power , fault fundamental positive sequence voltage ; Calculate fault duration , then make fault type judgment; Calculate simulation setting fault impedance or ; In step 3, the specific process of fault type judgment is as follows: (1) the effective value of the three-phase voltage during the steady-state interval during a fault, normalized to the effective value of the fundamental positive-sequence voltage , , as compared to the normalized value of the fundamental positive-sequence voltage ; (2) If the difference between the effective value unit of the three-phase voltage , , and the unit of the fundamental positive sequence voltage is within 1% , the fault type is a symmetrical fault; that is , and , and , it is a symmetrical fault; (3) If the difference between the effective value unit of the three-phase voltage , , and the unit of the fundamental positive sequence voltage is not all within the range of 1% , the fault type is an asymmetric fault; that is , or , or , it is an asymmetric fault; Step 4, power flow calculation: Substitute electromechanical transient simulation model, set initial voltage , active power , reactive power , carry out power flow calculation; set fault type, fault duration , fault impedance Or ; simulate fault ride through in electromechanical transient simulation software, obtain electromechanical transient simulation fault ride through test data; Step 5, deviation calculation and correction: Based on the fault interval division, the deviation of the measured or hardware-in-the-loop simulation fault ride-through test data and the electromechanical transient simulation fault ride-through test data of the fundamental positive sequence voltage is calculated before, during and after the fault; If the deviation meets the requirements, the next step is performed; Otherwise, correct the fault impedance or renew the electro-mechanical transient simulation; Step 6, final deviation analysis: Based on the fault interval division, the deviation of the measured or hardware-in-the-loop simulation and the electromechanical transient simulation fault ride-through test data of the fundamental positive sequence active power, reactive power, active current and reactive current is calculated, and the deviation is divided into pre-fault, fault period and post-fault transient and steady state periods; If all the deviations meet the requirements, it means that the new energy unit electromechanical transient simulation model meets the requirements; otherwise, it means that the new energy unit electromechanical transient simulation model does not meet the requirements.

2. The method of claim 1, wherein the method further comprises: In step 1, the fault ride-through data refers to: the effective value of the phase voltage of the three phases falls to 0% , 20% , 35% , 50% , 75% the effective value of the line voltage of only two phases falls to 0% , 20% , 35% , 50% , 75% ; the effective value of the phase voltage of the three phases is raised to 130 , 125 , 120 , 115 , the effective value of the line voltage of only two phases is raised to 130 , 125 , 120 , 115 .

3. The method of claim 1, wherein the method further comprises: determining a plurality of parameters of the new energy unit electromechanical transient simulation model; and determining a plurality of parameters of the new energy unit electromechanical transient simulation model based on the plurality of parameters of the new energy unit electromechanical transient simulation model. In step 2, the interval division of the data is as follows: Based on the fundamental positive sequence voltage, the three stages of pre-fault, fault period and post-fault are divided, which are as follows: ① voltage amplitude is less than 0.9 or greater than 1.1 20 ms before the time is before the failure; ② voltage amplitude is less than 0.9 or greater than 1.1 20 ms before the time when the voltage amplitude is greater than 0.9 or less than 1.1 within 20 ms before the time is a fault period; ③ voltage amplitude greater than 0.9 or less than 1.1 20 ms before the time is after the failure; Based on the fundamental positive sequence active current, the steady state and transient interval of the fault is divided, and the specific method is as follows: ① voltage amplitude is less than 0.9 or greater than 1.1 The time from 20 ms before to 1 s before the fault is the pre-fault steady state interval. ② After the voltage drop or voltage rise during the fault, the moment when the fundamental positive sequence active current enters the steady state value is the transient interval during the fault; from the moment when the fundamental positive sequence active current enters the steady state value after 20 ms, to the moment before 20 ms when the voltage amplitude is greater than 0.9 or less than 1.1 , is the steady state interval during the fault; ③ After fault, voltage amplitude is greater than 0.9 or less than 1.1 The time from 20 ms before the steady state value of the fundamental positive sequence active current to 20 ms after the steady state value is the post-fault transient interval. The fundamental positive sequence active current enters the steady state value after 20ms to 2s, which is the post-fault steady state period.

4. The method of claim 1, wherein the method further comprises: In step 3, fault impedance for the fault impedance in case of a symmetrical fault, fault impedance for the fault impedance in case of an asymmetrical fault; the calculation is as follows: Fault impedance Is: wherein is the fundamental positive sequence voltage; is the impedance value of the system in the electromechanical simulation; is the reference voltage of the system, which is the voltage value of the system in the fault-free state; Fault point voltage Is: According to the above equation, the fault impedance The calculation is as follows: 。 5. The method of claim 1, wherein the method further comprises: In steps 5 and 6, the deviation of each interval refers to the average deviation, average absolute deviation, maximum deviation and maximum value of the weighted average absolute deviation as follows: The deviation values of the steady state period and the transient interval are relatively consistent; all kinds of power parameters: fundamental positive sequence voltage, active power, reactive power, active current and reactive current, all show the same deviation value before, during and after the fault; in terms of numerical value, the main deviation is between 0.02 fundamental voltage and 0.10 active and reactive power and current; The trend of the average absolute deviation and the average deviation is similar, and the deviation values of the steady state and the transient state remain consistent; The deviation values of all kinds of parameters are the same as the average deviation, which are 0.02 to 0.10; The maximum deviation in the steady-state interval and the transient-state interval is the same maximum deviation value; the maximum deviation of the fundamental positive sequence voltage is 0.05, while the maximum deviation of other parameters, such as active power, reactive power, active current and reactive current, is 0.15, which shows similarity; The weighted average absolute deviation of all power parameters is 0.15, indicating that the influence of the deviation of each parameter is consistent in the weighted calculation.

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