A method and system for testing the disturbance response of a grid-forming converter

Abstract

This invention discloses a disturbance response testing method and system for a grid-type converter. The method includes acquiring time-domain electrical quantity data of the converter under test under a preset disturbance to extract steady-state characteristic data and disturbance response characteristic data; obtaining static voltage and static frequency evaluation results based on the steady-state characteristic data; obtaining non-functional and functional quantity evaluation results based on the time-domain electrical quantity data and the steady-state characteristic data; obtaining dynamic voltage evaluation results based on the static voltage evaluation results, disturbance response characteristic data, and non-functional quantity evaluation results; obtaining dynamic frequency evaluation results based on the static frequency evaluation results, functional quantity evaluation results, disturbance response characteristic data, and time-domain electrical quantity data; obtaining grid-type evaluation results based on the non-functional and functional quantity evaluation results; and obtaining disturbance response test results based on the dynamic voltage, dynamic frequency, and grid-type evaluation results to improve test accuracy.

Description

Technical Field

[0001] This invention relates to the field of power electronics and new energy grid connection technology, specifically to a disturbance response testing method and system for grid-connected converters. Background Technology

[0002] With the advancement of the "dual carbon" target, the penetration rate of new energy sources such as wind power and photovoltaics continues to increase. Currently, most new energy power generation units use grid-connected converters, which are highly dependent on the voltage and frequency references provided by the grid. They provide almost no rotational inertia or short-circuit capacity themselves, leading to a decrease in system inertia, weakened disturbance resistance, and increasingly prominent frequency and voltage stability issues. To address this, grid-connected energy storage converters have emerged. These converters can simulate the external characteristics of synchronous generators, autonomously construct voltage and frequency, and actively provide virtual inertia, damping, and voltage / reactive power support. They are considered key equipment for supporting the safe and stable operation of high-proportion new energy power systems.

[0003] However, existing technologies have significant shortcomings in evaluating the support capabilities of grid-connected energy storage converters: on the one hand, various indicators are isolated from each other, lacking a unified, comprehensive, and comparable evaluation framework, making it difficult to objectively compare equipment from different manufacturers and with different control strategies; on the other hand, existing evaluations mostly focus on steady-state characteristics, failing to characterize the dynamic response performance of the equipment during disturbances, and also neglecting differentiated evaluations based on different application scenarios such as weak grids, islanding, and black start. This hinders the promotion and application of high-performance grid-connected equipment and restricts the safe and stable construction of new power systems. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention discloses a disturbance response testing method and system for grid-type converters, which improves the accuracy of the test.

[0005] To achieve the above objectives, this invention discloses a disturbance response testing method for a grid-type converter, comprising: The time-domain electrical quantity data of the grid-type converter under test is obtained under a preset disturbance sequence, so as to obtain the steady-state characteristic data and disturbance response characteristic data of the grid-type converter under test based on the time-domain electrical quantity data; Based on the operating steady-state characteristic data, obtain the static voltage steady-state evaluation results and static frequency steady-state evaluation results of the grid converter under test; Based on the time-domain electrical quantity data and the operating steady-state characteristic data, obtain the non-functional steady-state evaluation results and functional steady-state evaluation results of the grid-type converter under test; The dynamic voltage steady-state evaluation results of the grid converter under test are obtained based on the static voltage steady-state evaluation results, the disturbance response characteristic data, and the non-functional quantity steady-state evaluation results. The dynamic frequency steady-state evaluation result of the grid-type converter under test is obtained based on the static frequency steady-state evaluation result, the functional quantity steady-state evaluation result, the disturbance response characteristic data, and the time-domain electrical quantity data. The steady-state evaluation results of the grid-type converter under test are obtained based on the steady-state evaluation results of the non-functional quantities and the steady-state evaluation results of the functional quantities. The disturbance response test results of the grid-type converter under test are obtained based on the dynamic voltage steady-state evaluation results, the dynamic frequency steady-state evaluation results, and the grid-type steady-state evaluation results.

[0006] This invention discloses a disturbance response testing method for a grid-type converter. First, it acquires time-domain electrical quantity data and extracts steady-state characteristic data and disturbance response characteristic data to simultaneously collect steady-state final values ​​and dynamic process information, providing a raw data foundation for subsequent multi-dimensional evaluation. Second, it obtains static voltage and static frequency evaluation results based on the steady-state characteristic data to quantify the converter's steady-state support capability after the disturbance ends, reflecting its static characteristics such as droop control. Next, it obtains steady-state evaluation results for reactive and reactive quantities based on the time-domain electrical quantity data and the steady-state characteristic data, introducing energy constraints from the energy storage battery to quantify the converter's energy sustainability over a long time scale. Finally, it compares the static voltage evaluation results with the disturbance response... The characteristic data and the steady-state evaluation results of reactive power are fused to obtain the dynamic voltage evaluation results, which are then used to dynamically correct the disturbance characteristic data on the static basis. Subsequently, the static frequency evaluation results are fused with the steady-state evaluation results of active power, disturbance response characteristic data, and time-domain electrical quantity data to obtain the dynamic frequency evaluation results, so as to introduce dynamic indicators and comprehensively characterize the full-stage response of frequency disturbances. Next, the steady-state evaluation results of the grid structure are obtained based on the steady-state evaluation results of reactive and reactive power, reflecting the physical fact that insufficient active or reactive energy becomes a persistent bottleneck. Finally, the disturbance response test results are obtained by weighted summation of the dynamic voltage, dynamic frequency, and steady-state evaluation results of the grid structure, which facilitates a direct comparison of the overall performance of different devices. In summary, the method disclosed in this application covers the transient performance in the voltage and frequency domains, respectively, and the grid evaluation results cover long-term energy sustainability. The three are fused through scenario-adaptive weighted fusion, which enables the evaluation results to distinguish the dynamic differences of different control strategies and adapt to different engineering requirements such as weak grids, islanding, and black starts. This provides a complete technical solution for the unified quantitative evaluation of grid-type converters and improves the accuracy of testing.

[0007] As a preferred example, the step of acquiring time-domain electrical quantity data of the grid-type converter under test under a preset disturbance sequence, and then acquiring the steady-state operating characteristic data and disturbance response characteristic data of the grid-type converter under test based on the time-domain electrical quantity data, includes: Obtain the converter model corresponding to the grid-type converter under test and the equivalent power grid model connected to the converter model; The equivalent power grid model is connected to the converter model through a common connection point, and a preset disturbance sequence is applied at the common connection point to obtain the time-domain electrical quantity data of the grid-type converter under test; wherein, the time-domain electrical quantity data includes the power grid time-series electrical quantity at the common connection point and the converter time-series electrical quantity at the AC output port of the converter model; The disturbance response characteristic data of the grid-type converter under test are obtained based on the time-series electrical quantities of the power grid, and the steady-state operating characteristic data of the grid-type converter under test are obtained based on the time-series electrical quantities of the power grid and the time-series electrical quantities of the converter.

[0008] The above scheme acquires the converter model and equivalent power grid model and connects them through the point of common coupling (PCC), establishing a standardized testing environment that allows different devices to be compared and tested under the same conditions. Secondly, a preset disturbance sequence is applied at the PCC, clearly defining the disturbance application location as the interface between the power grid and the converter, ensuring that the disturbance impact is reflected simultaneously on both the power grid side and the converter side. Next, the power grid time-series electrical quantities at the PCC and the converter time-series electrical quantities at the converter's AC output port are acquired, distinguishing between the power grid state (voltage, frequency) and the converter response behavior (active and reactive power), enabling the subsequent extraction of disturbance response characteristics (from the power grid waveform) and steady-state operating characteristics (from the difference between the two sides). Finally, disturbance response characteristic data is obtained based on the power grid time-series electrical quantities, and steady-state operating characteristic data is obtained based on the power grid and converter time-series electrical quantities.

[0009] As a preferred example, the power grid time-series electrical quantities include the power grid voltage time-series waveform, the power grid frequency time-series waveform, and the power grid frequency change rate time-series waveform; the converter time-series electrical quantities include the converter active power time-series waveform and the converter reactive power waveform. The process of obtaining disturbance response characteristic data of the grid-connected converter under test based on the grid time-series electrical quantities and obtaining steady-state operating characteristic data of the grid-connected converter under test based on the grid time-series electrical quantities and the converter time-series electrical quantities includes: The disturbance response characteristic data of the grid-type converter under test are obtained based on the grid voltage time-series waveform or the grid frequency time-series waveform; wherein, the disturbance response characteristic data includes response time, overshoot, settling time and damping ratio; The voltage deviation is obtained based on the power grid voltage timing waveform, and the frequency deviation is obtained based on the power grid frequency timing waveform; The frequency change rate is obtained from the time-series waveform of the power grid frequency change rate, and the active power change is obtained from the time-series waveform of the converter active power. The reactive power change is obtained based on the reactive power waveform of the converter, and the voltage deviation, frequency deviation, frequency change rate, active power change, and reactive power change are used as the steady-state characteristic data of the grid-type converter under test.

[0010] The above scheme obtains response time, overshoot, settling time, and damping ratio as disturbance response characteristic data based on the grid voltage or frequency time-series waveforms. It extracts core parameters from control theory describing the dynamic process: response time reflects speed (time to first enter the error band), overshoot reflects stability (peak deviation), settling time reflects accuracy (final settling time), and damping ratio reflects oscillation decay characteristics. These parameters directly quantify the converter's behavior throughout the entire process after a disturbance occurs. Secondly, it obtains voltage deviation from the grid voltage waveform, frequency deviation from the grid frequency waveform, and frequency change rate from the frequency change rate waveform. This step extracts the input conditions for the converter's steady-state support capability. Next, it obtains active power change from the converter's active power waveform and reactive power change from the converter's reactive power waveform. This step extracts the converter's response amplitude to disturbances. These deviations and changes are used as steady-state characteristic data, complementing the dynamic characteristic data.

[0011] As a preferred example, the step of obtaining the static voltage steady-state evaluation results and static frequency steady-state evaluation results of the grid-type converter under test based on the operating steady-state characteristic data includes: Obtain the rated capacity, rated voltage, and rated frequency of the grid-type converter under test; Based on the rated capacity, the rated voltage, and the voltage deviation and reactive power change in the operating steady-state characteristic data, the reactive power response ratio of the grid-type converter under test to the voltage deviation is obtained, and the reactive power response ratio is used as the static voltage steady-state evaluation result. Based on the rated capacity, the rated frequency, and the active power change and frequency deviation in the steady-state characteristic data, the first active power response ratio of the grid-type converter under test to the frequency deviation is obtained. Based on the rated capacity, the rated frequency, and the active power change and frequency change rate in the steady-state characteristic data, obtain the second active power response ratio of the grid-type converter under test to the frequency change rate; Norm fusion is performed on the first active response ratio and the second active response ratio to obtain the static frequency steady-state evaluation result.

[0012] The above scheme quantifies the steady-state support capability of the converter by constructing static voltage evaluation results (reactive power response ratio) and static frequency evaluation results (norm fusion of frequency deviation support component and frequency change rate support component). First, the rated capacity, rated voltage, and rated frequency are obtained. This step provides a benchmark for dimensionless processing, ensuring the evaluation results are unaffected by the equipment capacity level. Second, the reactive power response ratio is calculated based on the voltage deviation and reactive power change as the static voltage evaluation result. This feature, based on the converter's reactive power-voltage droop control physical characteristics, quantifies the reactive power that can be mobilized per unit voltage deviation, and is the core static indicator of voltage support capability. Next, the first active power response ratio (frequency deviation support index) is calculated based on the active power change and frequency deviation. This feature, based on the active power-frequency droop control characteristics, quantifies the active power that can be mobilized per unit frequency deviation. Then, the second active power response ratio (frequency change rate support index) is calculated based on the active power change and frequency change rate. This feature, based on virtual inertia characteristics, quantifies the active power that can be mobilized per unit frequency change rate, reflecting the converter's response capability to frequency change rate. Finally, the first and second active response ratios are fused using norm fusion (such as Euclidean norm) to obtain the static frequency assessment result. This feature combines frequency deviation support and frequency change rate support with equal weight, avoiding the dominance of a single indicator in the evaluation result, and can more comprehensively reflect the converter's overall response capability to frequency disturbances.

[0013] As a preferred example, the step of obtaining the non-functional steady-state evaluation results and functional steady-state evaluation results of the grid-type converter under test based on the time-domain electrical quantity data and the operating steady-state characteristic data includes: Based on the converter reactive power waveform in the time-domain electrical quantity data, obtain the first reactive power quantity of the grid-type converter under test; The state of charge, battery capacity, linear bus voltage, and power efficiency of the grid-type converter under test are obtained, so as to obtain the second non-functional quantity and the first functional quantity of the grid-type converter under test based on the state of charge, the battery capacity, the linear bus voltage, and the power efficiency. Obtain the first ratio of the second reactive power to the first reactive power, and obtain the first minimum value between the first ratio and a preset energy threshold, so as to use the first minimum value as the steady-state evaluation result of the reactive power of the grid-type converter under test. Based on the converter active power timing waveform in the time-domain electrical quantity data, the second active power quantity of the grid-type converter under test is obtained. Obtain a second ratio between the second functional quantity and the first functional quantity, and obtain a second minimum value between the second ratio and a preset energy threshold, so as to use the second minimum value as the steady-state evaluation result of the functional quantity of the grid-type converter under test.

[0014] The above scheme obtains the first reactive power quantity (i.e., the reactive power quantity required during disturbances) based on the converter reactive power waveform. This feature is obtained by integrating the reactive power time-series waveform, reflecting the reactive power reserve consumed to support the voltage. Secondly, it obtains the second reactive power quantity and the first active power quantity (i.e., available reactive and active power quantities) based on the state of charge, battery capacity, DC bus voltage, and charge / discharge efficiency. This feature incorporates the actual state of the energy storage system into the evaluation; available energy changes linearly with SOC, returning to zero when below the lower limit. Next, it obtains the first ratio of the second reactive power quantity to the first reactive power quantity, and obtains the first minimum value between the first ratio and a preset energy threshold as the steady-state evaluation result of the reactive power quantity. This feature achieves normalization by taking the smaller value of the ratio than 1. When the required energy exceeds the available energy, the evaluation result is limited to below 1, reflecting the limitation of insufficient energy on voltage support. Then, based on the active power waveform, a second active power quantity (required active power quantity) is obtained, and a second ratio of the second active power quantity to the first active power quantity is obtained. The second minimum value between the second ratio and a preset energy threshold is then used as the steady-state evaluation result of the active power quantity. Similarly, the energy constraints in frequency support are quantified. These features work together: the required energy quantifies the energy consumption demand of the energy storage system due to disturbances, the available energy reflects the actual supply capacity of the energy storage system, and the ratio of the two reflects the "energy margin," enabling this method to evaluate the sustainable support capacity of the converter over long time scales (seconds to minutes).

[0015] As a preferred example, obtaining the dynamic voltage steady-state evaluation result of the grid-type converter under test based on the static voltage steady-state evaluation result, the disturbance response characteristic data, and the non-functional quantity steady-state evaluation result includes: Based on the response time in the disturbance response characteristic data, the response speed term is obtained; wherein, the response speed term is inversely proportional to the response time. Based on the overshoot in the disturbance response characteristic data, a stationarity suppression term is obtained; wherein the stationarity suppression term decays exponentially with the increase of the overshoot. Based on the damping ratio in the disturbance response characteristic data, a damping ratio enhancement term is obtained; wherein, the damping ratio enhancement term increases linearly with the increase of the damping ratio; Multiply the static voltage steady-state evaluation result, the response speed term, the stability suppression term, the damping ratio enhancement term, and the non-functional quantity steady-state evaluation result to obtain the dynamic voltage steady-state evaluation result of the grid-type converter under test.

[0016] The above scheme obtains a response speed term (inversely proportional to response time) based on response time. This feature quantifies how quickly the converter responds to voltage disturbances: the shorter the response time, the larger the response speed term, stimulating a fast response. Secondly, a stability suppression term (exponentially decaying with overshoot) is obtained based on overshoot. This feature penalizes excessive overshoot: the larger the overshoot, the smaller the stability suppression term, and the exponential decay causes the penalty to increase sharply with increasing overshoot, suppressing the risk of oscillation. Next, a damping ratio enhancement term (linearly increasing with damping ratio) is obtained based on damping ratio, stimulating appropriate damping to quickly quell oscillations. Then, the static voltage evaluation result (reflecting steady-state gain), the response speed term (reflecting speed), the stability suppression term (reflecting stability), the damping ratio enhancement term (reflecting damping characteristics), and the reactive power evaluation result (reflecting energy sustainability) are multiplied to obtain the dynamic voltage evaluation result.

[0017] As a preferred example, obtaining the dynamic frequency steady-state evaluation result of the grid-type converter under test based on the static frequency steady-state evaluation result, the functional quantity steady-state evaluation result, the disturbance response characteristic data, and the time-domain electrical quantity data includes: The maximum frequency deviation after disturbance is extracted from the power grid frequency time-series waveform in the time-domain electrical quantity data, and a deviation suppression term is constructed based on the maximum frequency deviation; wherein, the deviation suppression term is inversely proportional to the maximum frequency deviation; Based on the settling time in the disturbance response characteristic data, a settling time term is constructed; wherein, the settling time term decays exponentially as the settling time increases; Based on the frequency damping ratio of the power grid frequency time-series waveform, a frequency damping ratio enhancement term is constructed; wherein, the frequency damping ratio enhancement term increases linearly with the increase of the frequency damping ratio; The dynamic frequency steady-state evaluation result of the grid-type converter under test is obtained by multiplying the static frequency steady-state evaluation result, the deviation suppression term, the adjustment time term, the frequency damping ratio enhancement term, and the functional quantity steady-state evaluation result.

[0018] The above scheme constructs a deviation suppression term (inversely proportional to the maximum frequency deviation) based on the maximum frequency deviation. This feature quantifies the converter's ability to suppress frequency peak deviations: the smaller the maximum frequency deviation, the larger the deviation suppression term, reflecting the device's ability to effectively "block" excessive frequency drops or rises. Secondly, a settling time term (exponentially decaying with settling time) is constructed based on the settling time. This feature quantifies the speed of frequency recovery: the shorter the settling time, the larger the settling time term, and the exponential decay causes a sharp drop in the score of devices with slow recovery. Next, a frequency damping ratio enhancement term (linearly increasing with frequency damping ratio) is constructed based on the frequency waveform damping ratio. This feature, based on second-order system damping theory, excites the rapid calming of frequency oscillations, preventing the frequency from repeatedly crossing the rated value during recovery. Finally, the static frequency evaluation result (reflecting steady-state gain), the deviation suppression term (reflecting peak suppression), the settling time term (reflecting recovery speed), the frequency damping ratio enhancement term (reflecting oscillation damping), and the functional quantity evaluation result (reflecting energy sustainability) are multiplied to obtain the dynamic frequency evaluation result.

[0019] As a preferred example, obtaining the grid-connected steady-state evaluation result of the tested grid-connected converter based on the non-functional steady-state evaluation result and the functional steady-state evaluation result includes: Obtain the minimum value between the steady-state evaluation result of the non-functional quantity and the steady-state evaluation result of the functional quantity; Based on the state of charge of the grid-connected converter under test, the state of charge availability factor of the grid-connected converter under test is obtained; wherein, the state of charge availability factor increases linearly with the state of charge and is zero when the state of charge is lower than a preset threshold; Multiplying the minimum value by the state-of-charge availability factor yields the steady-state evaluation result of the grid-type converter under test.

[0020] The above scheme obtains the minimum value between the active and non-active energy assessment results, which is consistent with the physical constraints of actual converter operation (for example, even with sufficient reactive power reserves, the converter cannot maintain frequency support if active power is depleted). Secondly, the state-of-charge (SOC) availability factor is obtained based on the SOC (which increases linearly with SOC and becomes zero below a threshold). This feature reflects the actual available energy range of the energy storage system, conforming to the engineering constraints of the battery management system on the depth of discharge and upper limit of charging. Then, the minimum value is multiplied by the SOC availability factor to obtain the grid-connected steady-state assessment result. This feature combines the energy bottleneck with SOC availability, reflecting the energy margin required relative to the current disturbance. The SOC availability factor reflects the state of the energy storage system itself; the multiplication of the two truly characterizes the converter's sustainable grid-connected capability over a long timescale.

[0021] As a preferred example, obtaining the disturbance response test results of the grid-type converter under test based on the dynamic voltage steady-state evaluation results, the dynamic frequency steady-state evaluation results, and the grid-type steady-state evaluation results includes: Based on the application scenario type of the grid-type converter under test, determine the first weight corresponding to the dynamic voltage steady-state evaluation result, the second weight corresponding to the dynamic frequency steady-state evaluation result, and the third weight corresponding to the grid steady-state evaluation result. The disturbance response test result of the grid-type converter under test is obtained by multiplying the dynamic voltage steady-state evaluation result by the first weight, the dynamic frequency steady-state evaluation result by the second weight, and the grid-type steady-state evaluation result by the third weight.

[0022] The above scheme determines the first, second, and third weights based on the application scenario of the grid-type converter under test. This feature allows for differentiated weight combinations for different scenarios such as weak grids, islanding, and black starts. Next, the dynamic voltage evaluation result is multiplied by the first weight, the dynamic frequency evaluation result by the second weight, and the grid steady-state evaluation result by the third weight, and then summed to obtain the disturbance response test result. This feature outputs a single comprehensive index, facilitating a direct comparison of the overall performance of different devices.

[0023] On the other hand, the present invention also discloses a disturbance response testing system for a grid-type converter, including a disturbance module, a static evaluation module, an energy evaluation module, a dynamic voltage module, a dynamic frequency module, a grid evaluation module, and a response testing module. The disturbance module is used to acquire time-domain electrical quantity data of the grid-type converter under test under a preset disturbance sequence, so as to acquire the steady-state operating characteristic data and disturbance response characteristic data of the grid-type converter under test based on the time-domain electrical quantity data; The static evaluation module is used to obtain the static voltage steady-state evaluation result and the static frequency steady-state evaluation result of the grid-type converter under test based on the operating steady-state characteristic data. The energy assessment module is used to obtain the non-functional steady-state assessment results and functional steady-state assessment results of the grid-type converter under test based on the time-domain electrical quantity data and the operating steady-state characteristic data. The dynamic voltage module is used to obtain the dynamic voltage steady-state evaluation result of the grid converter under test based on the static voltage steady-state evaluation result, the disturbance response characteristic data and the non-functional quantity steady-state evaluation result. The dynamic frequency module is used to obtain the dynamic frequency steady-state evaluation result of the grid-type converter under test based on the static frequency steady-state evaluation result, the functional quantity steady-state evaluation result, the disturbance response characteristic data, and the time-domain electrical quantity data. The network evaluation module is used to obtain the network steady-state evaluation result of the tested network converter based on the non-functional steady-state evaluation result and the functional steady-state evaluation result. The response test module is used to obtain the disturbance response test results of the grid-type converter under test based on the dynamic voltage steady-state evaluation results, the dynamic frequency steady-state evaluation results, and the grid-type steady-state evaluation results.

[0024] This invention discloses a disturbance response testing system for a grid-type converter. First, it acquires time-domain electrical quantity data and extracts steady-state characteristic data and disturbance response characteristic data to simultaneously collect steady-state final values ​​and dynamic process information, providing a raw data foundation for subsequent multi-dimensional evaluation. Second, it obtains static voltage and static frequency evaluation results based on the steady-state characteristic data to quantify the converter's steady-state support capability after the disturbance ends, reflecting its static characteristics such as droop control. Next, it obtains steady-state evaluation results for reactive and reactive quantities based on the time-domain electrical quantity data and the steady-state characteristic data, introducing energy constraints from the energy storage battery to quantify the converter's energy sustainability over a long time scale. Finally, it compares the static voltage evaluation results with the disturbance response... The characteristic data and the steady-state evaluation results of reactive power are fused to obtain the dynamic voltage evaluation results, which are then used to dynamically correct the disturbance characteristic data on the static basis. Subsequently, the static frequency evaluation results are fused with the steady-state evaluation results of active power, disturbance response characteristic data, and time-domain electrical quantity data to obtain the dynamic frequency evaluation results, so as to introduce dynamic indicators and comprehensively characterize the full-stage response of frequency disturbances. Next, the steady-state evaluation results of the grid structure are obtained based on the steady-state evaluation results of reactive and reactive power, reflecting the physical fact that insufficient active or reactive energy becomes a persistent bottleneck. Finally, the disturbance response test results are obtained by weighted summation of the dynamic voltage, dynamic frequency, and steady-state evaluation results of the grid structure, which facilitates a direct comparison of the overall performance of different devices. In summary, the method disclosed in this application covers the transient performance in the voltage and frequency domains, respectively, and the grid evaluation results cover long-term energy sustainability. The three are fused through scenario-adaptive weighted fusion, which enables the evaluation results to distinguish the dynamic differences of different control strategies and adapt to different engineering requirements such as weak grids, islanding, and black starts. This provides a complete technical solution for the unified quantitative evaluation of grid-type converters and improves the accuracy of testing. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1This is a flowchart illustrating a disturbance response testing method for a grid-type converter disclosed in an embodiment of the present invention; Figure 2 This is a comparative verification diagram of the frequency support dynamic response capability of a grid-type energy storage converter disclosed in an embodiment of the present invention; wherein, the solid line represents device A controlled by a virtual synchronous generator (VSG), and the dashed line represents device B controlled by a traditional droop control. Figure 3 This is a comparative verification diagram of the voltage support dynamic response capability of a grid-type energy storage converter disclosed in an embodiment of the present invention; wherein, the solid line represents device A controlled by a virtual synchronous generator (VSG), and the dashed line represents device B controlled by a traditional droop control. Figure 4 This is a schematic diagram of the disturbance response testing system for a grid-type converter disclosed in an embodiment of the present invention. Detailed Implementation

[0027] 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.

[0028] With the deepening implementation of the "dual-carbon" strategic goals, the installed capacity of new energy power generation, represented by wind power and photovoltaics, has continued to grow rapidly, and its penetration rate in the power system has been increasing. However, new energy power generation units are generally connected to the grid through grid-following (GFL) converters. This mode is highly dependent on the voltage and frequency reference provided by the grid, and provides little or no rotational inertia and short-circuit capacity itself. This structural change has led to a significant decrease in the overall inertia level of the traditional power system, weakened system strength, reduced disturbance resistance, and increasingly prominent frequency and voltage stability issues, posing a severe challenge to the safe and stable operation of the power grid.

[0029] To address these challenges, grid-forming (GFM) control technology has emerged. Grid-forming power conversion systems (GFM-PCS) can simulate the external characteristics of synchronous generators, autonomously constructing and maintaining internal voltage and frequency, and actively providing virtual inertia, damping, and voltage / reactive power support to the grid, thereby effectively improving the stability and resilience of new power systems. Therefore, GFM-PCS is considered a key piece of equipment supporting the safe and stable operation of high-proportion renewable energy power systems, and its technological development and application have received widespread attention from academia and industry.

[0030] While existing technologies have provided preliminary quantification of various support capability indicators for grid-connected energy storage converters, these indicators are isolated and lack a unified, comprehensive, and comparable evaluation framework. In practical engineering applications, grid-connected converters from different manufacturers and with different control strategies exhibit varying performance across different indicators. Power grid companies, equipment manufacturers, and owners find it difficult to make scientific and objective judgments about the overall grid performance based solely on fragmented indicator data. Current research on the performance evaluation of grid-connected converters typically focuses on testing or qualitatively describing single indicators, failing to consider the comprehensive evaluation of multi-dimensional support capability indicators such as voltage and frequency, and to differentiate evaluations based on specific application scenarios. In other words, a clear and intuitive comprehensive performance index has not been established. Furthermore, existing evaluation systems primarily focus on the steady-state characteristics of grid-connected energy storage converters, failing to characterize their dynamic response performance. Without effective dynamic quantification and evaluation of the comprehensive support capabilities of grid-connected converters, the promotion and application of high-performance grid-connected equipment will be hindered, impacting the safe and stable construction of new power systems.

[0031] To solve the above technical problems, refer to Figure 1 This embodiment discloses a disturbance response testing method for a grid-type converter, which improves the accuracy and efficiency of the test. Specifically, the method includes: Step 101: Obtain the time-domain electrical quantity data of the grid-type converter under test under a preset disturbance sequence, so as to obtain the steady-state characteristic data and disturbance response characteristic data of the grid-type converter under test based on the time-domain electrical quantity data.

[0032] Step 102: Obtain the static voltage steady-state evaluation results and static frequency steady-state evaluation results of the grid-type converter under test based on the operating steady-state characteristic data.

[0033] Step 103: Obtain the non-functional steady-state evaluation results and functional steady-state evaluation results of the grid-type converter under test based on the time-domain electrical quantity data and the operating steady-state characteristic data.

[0034] Step 104: Obtain the dynamic voltage steady-state evaluation result of the grid-type converter under test based on the static voltage steady-state evaluation result, the disturbance response characteristic data, and the non-functional quantity steady-state evaluation result.

[0035] Step 105: Obtain the dynamic frequency steady-state evaluation result of the grid-type converter under test based on the static frequency steady-state evaluation result, the functional quantity steady-state evaluation result, the disturbance response characteristic data, and the time-domain electrical quantity data.

[0036] Step 106: Obtain the grid-type steady-state evaluation result of the tested grid-type converter based on the steady-state evaluation results of the non-functional quantities and the steady-state evaluation results of the functional quantities.

[0037] Step 107: Obtain the disturbance response test results of the grid-type converter under test based on the dynamic voltage steady-state evaluation results, the dynamic frequency steady-state evaluation results, and the grid-type steady-state evaluation results.

[0038] This embodiment provides a disturbance response testing method for a grid-type converter. First, time-domain electrical quantity data is acquired, and steady-state characteristic data and disturbance response characteristic data are extracted to simultaneously collect steady-state final values ​​and dynamic process information, providing a raw data foundation for subsequent multi-dimensional evaluation. Second, static voltage and static frequency evaluation results are obtained based on the steady-state characteristic data to quantify the converter's steady-state support capability after the disturbance ends, reflecting its static characteristics such as droop control. Next, steady-state evaluation results of non-functional and functional quantities are obtained based on the time-domain electrical quantity data and steady-state characteristic data to introduce energy constraints from the energy storage battery and quantify the converter's energy sustainability over a long time scale. Finally, the static voltage evaluation results are compared with the disturbance response... The characteristic data and the steady-state evaluation results of reactive power are fused to obtain the dynamic voltage evaluation results, which are then used to dynamically correct the disturbance characteristic data on the static basis. Subsequently, the static frequency evaluation results are fused with the steady-state evaluation results of active power, disturbance response characteristic data, and time-domain electrical quantity data to obtain the dynamic frequency evaluation results, so as to introduce dynamic indicators and comprehensively characterize the full-stage response of frequency disturbances. Next, the steady-state evaluation results of the grid structure are obtained based on the steady-state evaluation results of reactive and reactive power, reflecting the physical fact that insufficient active or reactive energy becomes a persistent bottleneck. Finally, the disturbance response test results are obtained by weighted summation of the dynamic voltage, dynamic frequency, and steady-state evaluation results of the grid structure, which facilitates a direct comparison of the overall performance of different devices. In summary, the method disclosed in this application covers the transient performance in the voltage and frequency domains, respectively, and the grid evaluation results cover long-term energy sustainability. The three are fused through scenario-adaptive weighted fusion, which enables the evaluation results to distinguish the dynamic differences of different control strategies and adapt to different engineering requirements such as weak grids, islanding, and black starts. This provides a complete technical solution for the unified quantitative evaluation of grid-type converters and improves the accuracy of testing.

[0039] In this embodiment, step 101 includes: Step 1011: Obtain the converter model corresponding to the grid-type converter under test and the equivalent power grid model connected to the converter model; Step 1012: Connect the equivalent power grid model to the converter model through the point of common coupling, and apply a preset disturbance sequence at the point of common coupling to obtain the time-domain electrical quantity data of the grid-type converter under test; wherein, the time-domain electrical quantity data includes the power grid time-series electrical quantity at the point of common coupling and the converter time-series electrical quantity at the AC output port of the converter model; Step 1013: Obtain the disturbance response characteristic data of the grid-connected converter under test based on the grid time-series electrical quantities, and obtain the steady-state operating characteristic data of the grid-connected converter under test based on the grid time-series electrical quantities and the converter time-series electrical quantities; wherein, the grid time-series electrical quantities include the grid voltage time-series waveform, the grid frequency time-series waveform, and the grid frequency change rate time-series waveform; the converter time-series electrical quantities include the converter active power time-series waveform and the converter reactive power waveform; Step 1013 includes: Step 10131: Obtain the disturbance response characteristic data of the grid-connected converter under test based on the grid voltage time-series waveform or the grid frequency time-series waveform; wherein, the disturbance response characteristic data includes response time, overshoot, settling time, and damping ratio; Step 10132: Obtain the voltage deviation based on the power grid voltage timing waveform, and obtain the frequency deviation based on the power grid frequency timing waveform; Step 10133: Obtain the frequency change rate based on the time-series waveform of the power grid frequency change rate and obtain the active power change based on the time-series waveform of the converter active power; Step 10134: Obtain the reactive power change based on the reactive power waveform of the converter, and use the voltage deviation, frequency deviation, frequency change rate, active power change and reactive power change as the steady-state characteristic data of the grid-type converter under test.

[0040] In this embodiment, firstly, a simulation test scenario is constructed, comprising an equivalent power grid model and a model of the grid-connected converter under test. The equivalent power grid model consists of an equivalent voltage source and adjustable line impedance; the grid-connected converter under test is a simulation model of the grid-connected energy storage converter to be tested. The equivalent power grid model and the converter model are connected via a point of common coupling (PCC) to simulate the actual physical topology of the converter connected to the power grid.

[0041] Next, based on the preset disturbance data types and corresponding value ranges, a standardized multi-dimensional disturbance sequence is generated and applied at the common connection point. The disturbance sequence includes: voltage step disturbances with amplitudes of ±0.05 pu and ±0.1 pu; frequency step disturbances with amplitudes of ±0.1 Hz and ±0.2 Hz; and frequency change rate disturbances with values ​​of ±1 Hz / s and ±2 Hz / s. During application, each disturbance is applied sequentially according to a preset timing sequence to independently record the converter's response to each type of disturbance.

[0042] Furthermore, measurement modules are installed at the point of common coupling and at the AC output port of the converter model. After applying the multi-dimensional disturbance sequence, the raw electrical quantity data before and after the disturbance are collected synchronously in real time at a fixed sampling frequency (e.g., 10 kHz), including: grid time-series electrical quantities at the point of common coupling and grid voltage time-series waveforms. Power grid frequency timing waveform Time-series waveform of power grid frequency change rate The converter's timing electrical quantities at the AC output port include the three-phase voltage and current on the converter side, as well as the state of charge (SOC). Using instantaneous power theory, the converter's active power timing waveform is calculated based on the collected three-phase voltage and current on the converter side. Reactive power timing waveform of converter Plotting time on the horizontal axis, the electrical quantity data obtained from the above collection and calculation are connected to generate corresponding time-domain measured curves, which are used as the time-domain electrical quantity data.

[0043] According to the power grid voltage timing waveform Or the power grid frequency timing waveform Obtain the disturbance response characteristic data of the grid-type converter under test. The disturbance response characteristic data includes response time. Overshoot Adjusting time and damping ratio The specific extraction method is as follows: Response time Determine the time of the disturbance. The steady-state average value before the disturbance is calculated as the target steady-state value. or Set an error band (e.g., ±2%). From Start scanning the waveform backwards, find the first time t1 such that from that time onwards the waveform first enters and remains within the error band, then... =t1- .

[0044] Overshoot For positive disturbances, search for the maximum value in the waveform after the disturbance. (or For negative perturbations, search for the minimum value. (or ), to calculate overshoot: or .

[0045] Adjusting time From the moment the disturbance occurs Begin by finding the moment when the last waveform exits the error band. ,but = - Alternatively, find the first time point t2 such that all subsequent waveform points remain within the error band. =t2- .

[0046] Damping ratio The logarithmic decay method using adjacent peaks is employed. The amplitudes A1, A2, ..., An of consecutive oscillating peaks in the waveform are identified, and the logarithmic decay rate is calculated. Then the damping ratio is: .

[0047] According to the power grid voltage timing waveform Power grid frequency timing waveform Time-series waveform of power grid frequency change rate Converter active power timing waveform Reactive power timing waveform of converter Obtain steady-state characteristic data, specifically including: Voltage deviation Take the average voltage waveform during a stable window (e.g., 0.5 s) before the disturbance occurs. Take the average voltage waveform of the stable window after the disturbance ends. ,but = - .

[0048] Frequency deviation Similarly, take the difference between the average steady-state frequencies before and after the disturbance: = - Among them, the aforementioned The average frequency waveform value during a stable window (e.g., 0.5 s) before the disturbance occurs; This represents the average frequency waveform value of the stable window after the disturbance ends.

[0049] Rate of change of frequency The peak value (maximum absolute value) after the disturbance is extracted from the time-series waveform of the power grid frequency change rate as the frequency change rate characteristic value of the disturbance.

[0050] Change in active power Take the average steady-state active power before the disturbance. The average steady-state active power after the disturbance ,but = - .

[0051] Reactive power change Take the average steady-state reactive power before the disturbance. The average steady-state reactive power after the disturbance ,but = - .

[0052] The above voltage deviation Frequency deviation Rate of change of frequency Changes in active power and reactive power change This serves as the steady-state characteristic data of the tested grid-type converter.

[0053] The above implementation method acquires the converter model and equivalent power grid model and connects them through the point of common coupling, establishing a standardized test environment that allows different devices to be compared and tested under the same conditions. Secondly, a preset disturbance sequence is applied at the point of common coupling, clearly defining the disturbance application location as the interface between the power grid and the converter, ensuring that the disturbance impact is reflected simultaneously on both the power grid side and the converter side. Next, the power grid time-series electrical quantities at the point of common coupling and the converter time-series electrical quantities at the converter's AC output port are acquired, distinguishing between the power grid state (voltage, frequency) and the converter response behavior (active and reactive power), enabling the subsequent extraction of disturbance response characteristics (from the power grid side waveform) and steady-state operating characteristics (from the difference between the two sides). Finally, disturbance response characteristic data is obtained based on the power grid time-series electrical quantities, and steady-state operating characteristic data is obtained based on the power grid and converter time-series electrical quantities.

[0054] In this embodiment, step 102 includes: Step 1021: Obtain the rated capacity, rated voltage, and rated frequency of the grid-type converter under test; Step 1022: Based on the rated capacity, the rated voltage, and the voltage deviation and reactive power change in the operating steady-state characteristic data, obtain the reactive power response ratio of the grid-type converter under test to the voltage deviation, and use the reactive power response ratio as the static voltage steady-state evaluation result. Step 1023: Based on the rated capacity, the rated frequency, and the active power change and frequency deviation in the steady-state characteristic data, obtain the first active power response ratio of the grid-type converter under test to the frequency deviation; Step 1024: Based on the rated capacity, the rated frequency, and the active power change and frequency change rate in the steady-state characteristic data, obtain the second active power response ratio of the grid-type converter under test to the frequency change rate; Step 1025: Perform norm fusion on the first active response ratio and the second active response ratio to obtain the static frequency steady-state evaluation result.

[0055] In this embodiment, the factory rated parameters of the grid-type converter under test are obtained, including: rated capacity. Rated voltage and rated frequency These parameters are used to perform dimensionless processing on subsequent calculations, so that the evaluation results are not affected by the equipment capacity level.

[0056] Extract voltage deviation from the operating steady-state characteristic data and reactive power change Among them, voltage deviation The voltage time-series waveform taken at the point of common coupling is the difference between the average steady-state voltage before the disturbance and the average steady-state voltage after the disturbance; reactive power change. The reactive power timing waveform taken from the converter side is the difference between the average steady-state reactive power before the disturbance and the average steady-state reactive power after the disturbance.

[0057] According to the rated capacity Rated voltage Voltage deviation and reactive power change Calculate the reactive power response ratio of the grid-type converter under test to the voltage deviation, and use it as the static voltage steady-state evaluation result: This ratio reflects the reactive power that the converter can utilize per unit voltage deviation under steady-state conditions, and is a core static indicator of voltage support capability. The absolute value is used to unify the evaluation of positive and negative disturbances.

[0058] Based on the active power response behavior of the converter to frequency deviation and frequency change rate, a first active power response ratio and a second active power response ratio are constructed and then fused using norms. Specifically, the active power change is extracted from the steady-state characteristic data. Frequency deviation and frequency change rate Among them, the change in active power The active power timing waveform taken from the converter side is the difference between the average steady-state active power before the disturbance and the average steady-state active power after the disturbance; frequency deviation. The frequency-time waveform taken from the point of common coupling is the difference between the average steady-state frequency before the disturbance and the average steady-state frequency after the disturbance; the rate of frequency change. The frequency change rate time-series waveform taken from the common junction point is the peak value after disturbance.

[0059] Next, according to the rated capacity Rated frequency Changes in active power and frequency deviation Calculate the first active response ratio of the grid-type converter under test to the frequency deviation: This ratio reflects the active power that the converter can draw upon per unit frequency deviation under steady-state conditions, and embodies the droop control characteristics (primary frequency regulation capability) of the converter.

[0060] According to the rated capacity Rated frequency Changes in active power and frequency change rate Calculate the second active response ratio of the grid-type converter under test to the rate of frequency change: This ratio reflects the active power that the converter can draw upon at a unit frequency change rate, and embodies the virtual inertia characteristics of the converter.

[0061] For the first active response ratio and the second active response ratio Norm fusion is performed to obtain the static frequency steady-state evaluation results. In this embodiment, Euclidean norm (i.e., the square root of the sum of squares) is used for equal-weight fusion: The fusion result simultaneously covers the converter's response to frequency deviation and frequency change rate, avoiding the dominance of a single indicator in the evaluation, and can more comprehensively reflect the converter's overall static support performance under frequency disturbances.

[0062] The above implementation method quantifies the steady-state support capability of the converter by constructing static voltage evaluation results (reactive power response ratio) and static frequency evaluation results (norm fusion of frequency deviation support component and frequency change rate support component). First, the rated capacity, rated voltage, and rated frequency are obtained. This step provides a benchmark for dimensionless processing, ensuring the evaluation results are not affected by the equipment capacity level. Second, the reactive power response ratio is calculated based on the voltage deviation and reactive power change as the static voltage evaluation result. This feature, based on the converter's reactive power-voltage droop control physical characteristics, quantifies the reactive power that can be mobilized per unit voltage deviation, and is the core static indicator of voltage support capability. Next, a first active power response ratio (frequency deviation support index) is calculated based on the active power change and frequency deviation. This feature, based on the active power-frequency droop control characteristics, quantifies the active power that can be mobilized per unit frequency deviation. Then, a second active power response ratio (frequency change rate support index) is calculated based on the active power change and frequency change rate. This feature, based on virtual inertia characteristics, quantifies the active power that can be mobilized per unit frequency change rate, reflecting the converter's response capability to frequency change rate. Finally, the first and second active response ratios are fused using norm fusion (such as Euclidean norm) to obtain the static frequency assessment result. This feature combines frequency deviation support and frequency change rate support with equal weight, avoiding the dominance of a single indicator in the evaluation result, and can more comprehensively reflect the converter's overall response capability to frequency disturbances.

[0063] In this embodiment, step 103 includes: Step 1031: Obtain the first reactive power quantity of the grid-type converter under test based on the converter reactive power waveform in the time-domain electrical quantity data; Step 1032: Obtain the state of charge, battery capacity, linear bus voltage, and power efficiency of the grid-type converter under test, so as to obtain the second non-functional quantity and the first functional quantity of the grid-type converter under test based on the state of charge, the battery capacity, the linear bus voltage, and the power efficiency. Step 1033: Obtain the first ratio of the second reactive power quantity to the first reactive power quantity, and obtain the first minimum value between the first ratio and the preset energy threshold, so as to use the first minimum value as the reactive power steady-state evaluation result of the grid-type converter under test. Step 1034: Based on the converter active power time-series waveform in the time-domain electrical quantity data, obtain the second active power quantity of the grid-type converter under test; Step 1035: Obtain the second ratio of the second functional quantity to the first functional quantity, and obtain the second minimum value between the second ratio and the preset energy threshold, so as to use the second minimum value as the steady-state evaluation result of the functional quantity of the grid-type converter under test.

[0064] Based on the above-mentioned time-domain electrical quantity data acquisition and feature parameter extraction, this embodiment further calculates the steady-state evaluation results of non-functional quantities and the steady-state evaluation results of functional quantities according to the converter power waveform and energy storage system parameters. The specific process is as follows.

[0065] First, based on the converter reactive power timing waveform in the time-domain electrical quantity data... Calculate the reactive power required by the grid-type converter under test during the period from the occurrence of a disturbance to its recovery to stability, and denote it as the first reactive power. : in, The time when the disturbance occurs. The settling time (i.e., the settling time in the disturbance response characteristic data) is the integral interval from the start of the disturbance until the system returns to stability.

[0066] Obtain the state of charge (SOC) and battery capacity of the grid-connected converter under test. DC bus voltage and charge / discharge efficiency Based on these parameters, the available reactive power (second reactive power) and available active power (first active power) are calculated. Since the active and reactive power of the energy storage system both originate from the same battery pack, their available energy is numerically the same; therefore, the second reactive power... With the first functional power All are calculated using the following formula: =SOC ; =SOC ; In the formula, η is the charging and discharging efficiency of the converter (between 0 and 1).

[0067] Take the first nonfunctional quantity With the second nonfunctional quantity The ratio of 1 to 1 is used to compare the results, and the smaller value is taken as the steady-state assessment result of the non-active quantity. This ratio reflects the converter's ability to sustainably withstand voltage disturbances under current energy reserves. When available energy is greater than or equal to required energy, the evaluation result is 1 (full marks); when available energy is insufficient, the evaluation result is less than 1, and decreases linearly as the energy gap increases.

[0068] Based on the converter active power timing waveform in the time-domain electrical quantity data. Calculate the active power required by the grid-type converter under test during the period from the occurrence of a disturbance to its recovery to stability, and denote it as the second active power. : in, The time when the disturbance occurs. The settling time (i.e., the settling time in the disturbance response characteristic data) is the integral interval from the start of the disturbance until the system returns to stability.

[0069] Take the ratio of the first functional quantity to the second functional quantity, compare it with 1, and take the smaller value as the steady-state evaluation result of the functional quantity: This ratio reflects the converter's ability to sustainably withstand frequency disturbances with current energy reserves.

[0070] The above implementation obtains the first reactive power quantity (i.e., the reactive power quantity required during disturbances) based on the converter reactive power waveform. This feature is obtained by integrating the reactive power time-series waveform, reflecting the reactive power reserve consumed to support the voltage. Next, the second reactive power quantity and the first active power quantity (i.e., available reactive and active power quantities) are obtained based on the state of charge, battery capacity, DC bus voltage, and charge / discharge efficiency. This feature incorporates the actual state of the energy storage system into the evaluation; available energy changes linearly with SOC, returning to zero when below the lower limit. Then, the first ratio of the second reactive power quantity to the first reactive power quantity is obtained, and the first minimum value between the first ratio and a preset energy threshold is obtained as the steady-state evaluation result of the reactive power quantity. This feature achieves normalization by taking the smaller value of the ratio than 1. When the required energy exceeds the available energy, the evaluation result is limited to below 1, reflecting the limitation of insufficient energy on voltage support. Then, based on the active power waveform, a second active power quantity (required active power quantity) is obtained, and a second ratio of the second active power quantity to the first active power quantity is obtained. The second minimum value between the second ratio and a preset energy threshold is then used as the steady-state evaluation result of the active power quantity. Similarly, the energy constraints in frequency support are quantified. These features work together: the required energy quantifies the energy consumption demand of the energy storage system due to disturbances, the available energy reflects the actual supply capacity of the energy storage system, and the ratio of the two reflects the "energy margin," enabling this method to evaluate the sustainable support capacity of the converter over long time scales (seconds to minutes).

[0071] In this embodiment, step 104 includes: Step 1041: Obtain the response speed term based on the response time in the disturbance response characteristic data; wherein the response speed term is inversely proportional to the response time; Step 1042: Obtain a stationarity suppression term based on the overshoot in the disturbance response characteristic data; wherein the stationarity suppression term decays exponentially with the increase of the overshoot. Step 1043: Obtain the damping ratio enhancement term based on the damping ratio in the disturbance response characteristic data; wherein the damping ratio enhancement term increases linearly with the increase of the damping ratio; Step 1043: Multiply the static voltage steady-state evaluation result, the response speed term, the stability suppression term, the damping ratio enhancement term, and the non-functional quantity steady-state evaluation result to obtain the dynamic voltage steady-state evaluation result of the grid-type converter under test.

[0072] This embodiment, based on the obtained static voltage steady-state evaluation results, non-functional quantity steady-state evaluation results, and disturbance response characteristic data (response time, overshoot, damping ratio), further constructs dynamic voltage steady-state evaluation results to comprehensively quantify the converter's four-dimensional characteristics of "fast, stable, accurate, and durable" under voltage disturbances. The specific process is as follows.

[0073] First, based on the response time in the disturbance response characteristic data Get response speed item The response speed term is inversely proportional to the response time and is used to quantify how quickly the converter responds to voltage disturbances. In this embodiment, 20 ms is used as the baseline response time, and the specific calculation formula is as follows: in, Voltage response time is the time required for the voltage waveform to first enter and remain within the ±2% error band of the target steady-state value after a disturbance occurs. A shorter response time results in a higher voltage response time. The larger the value, the faster the incentive response.

[0074] Based on the overshoot in the disturbance response characteristic data Obtain the stationarity inhibition term The stationarity suppression term decays exponentially with increasing overshoot, and is used to penalize oscillations caused by excessive overshoot. In this embodiment, based on the overshoot theory of second-order systems, an exponentially decaying function is used, and the specific calculation formula is as follows: in, This refers to the maximum percentage deviation of the voltage waveform peak value from the target steady-state value. The larger the overshoot, the greater the deviation. The smaller the value, the more the penalty increases dramatically as the overshoot increases, due to the exponential decay.

[0075] Based on the damping ratio in the disturbance response characteristic data Obtain the damping ratio enhancement term The damping ratio enhancement term increases linearly with the increase of the damping ratio, and is used to excite appropriate damping to quickly quell oscillations. In this embodiment, based on the recommended critical damping value for control engineering (ζ≥0.7), a linear enhancement function is used, and the specific calculation formula is as follows: In the formula, The damping ratio is calculated using the logarithmic attenuation method of adjacent peaks on the voltage waveform. When When =0.7, =1; when When >0.7, >1 (Bonus points incentive); when When <0.7, <1 (penalty for deduction of points).

[0076] The static voltage steady-state evaluation results The response speed item The stationarity suppression term The damping ratio enhancement term Multiplying the static steady-state evaluation result FSIQ by the dynamic voltage steady-state evaluation result DVSI of the grid-type converter under test, we obtain the dynamic voltage steady-state evaluation result DVSI of the grid-type converter under test. This embodiment adopts a multiplicative fusion method to ensure that performance degradation in any dimension can significantly reduce the comprehensive index. The dynamic voltage steady-state evaluation result comprehensively quantifies the converter's static gain, response speed, overshoot suppression capability, damping characteristics, and energy sustainability under voltage disturbances, fully reflecting the support capability throughout the entire stage from disturbance occurrence to recovery of stability.

[0077] The above implementation method obtains a response speed term (inversely proportional to the response time) based on the response time. This feature quantifies how quickly the converter responds to voltage disturbances: the shorter the response time, the larger the response speed term, stimulating a fast response. Secondly, a stability suppression term (exponentially decaying with overshoot) is obtained based on the overshoot. This feature penalizes excessive overshoot: the larger the overshoot, the smaller the stability suppression term, and the exponential decay causes the penalty to increase sharply with increasing overshoot, suppressing the risk of oscillation. Next, a damping ratio enhancement term (linearly increasing with damping ratio) is obtained based on the damping ratio, stimulating appropriate damping to quickly quell oscillations. Then, the static voltage evaluation result (reflecting steady-state gain), the response speed term (reflecting speed), the stability suppression term (reflecting stability), the damping ratio enhancement term (reflecting damping characteristics), and the reactive power evaluation result (reflecting energy sustainability) are multiplied to obtain the dynamic voltage evaluation result.

[0078] In this embodiment, step 105 includes: Step 1051: Extract the maximum frequency deviation after disturbance from the power grid frequency time-series waveform in the time-domain electrical quantity data, and construct a deviation suppression term based on the maximum frequency deviation; wherein the deviation suppression term is inversely proportional to the maximum frequency deviation; Step 1052: Construct a settling time term based on the settling time in the disturbance response characteristic data; wherein the settling time term decays exponentially as the settling time increases; Step 1053: Based on the frequency damping ratio of the power grid frequency time-series waveform, construct a frequency damping ratio enhancement term; wherein, the frequency damping ratio enhancement term increases linearly with the increase of the frequency damping ratio; Step 1054: Multiply the static frequency steady-state evaluation result, the deviation suppression term, the adjustment time term, the frequency damping ratio enhancement term, and the active power steady-state evaluation result to obtain the dynamic frequency steady-state evaluation result of the grid-type converter under test.

[0079] This embodiment, based on the obtained static frequency steady-state evaluation results, functional quantity steady-state evaluation results, disturbance response characteristic data (adjustment time), and time-domain electrical quantity data (grid frequency time-series waveform), further constructs dynamic frequency steady-state evaluation results to comprehensively quantify the converter's four-dimensional characteristics of peak suppression, recovery speed, oscillation damping, and energy persistence under frequency disturbances. The specific process is as follows.

[0080] Based on the power grid frequency time-series waveform in the time-domain electrical quantity data Extract the maximum frequency deviation after disturbance The maximum frequency deviation is the maximum absolute value of the frequency waveform deviating from the rated frequency after the disturbance occurs, that is: According to the maximum frequency deviation Construct a bias suppression term The deviation suppression term is inversely proportional to the maximum frequency deviation and is used to quantify the converter's ability to suppress frequency peak deviation. In this embodiment, 0.2 Hz is used as the reference maximum frequency deviation, and the specific calculation formula is as follows: In the formula, The unit is Hz. The smaller the maximum frequency deviation, The larger the value, the more effectively the device can "block" excessive drops or increases in frequency.

[0081] Based on the settling time in the disturbance response characteristic data Construct adjustment time item The settling time term decays exponentially with increasing settling time, used to quantify the speed of frequency recovery. In this embodiment, based on the influence of settling time on system performance in control theory, an exponential decay function is used, and the specific calculation formula is as follows: In the formula, Settling time (in seconds) is the time required for the frequency waveform to stabilize within ±2% of the target steady-state value after a disturbance occurs and to no longer cross out of this range. A shorter settling time results in a more stable waveform. The larger the value, the more exponential decay occurs, causing the score to drop sharply when the adjustment time is too long.

[0082] Based on the frequency damping ratio of the power grid frequency time-series waveform Construct a frequency damping ratio enhancement term The frequency damping ratio enhancement term increases linearly with the increase of the frequency damping ratio, and is used to excite the rapid calming of frequency oscillations. In this embodiment, the same linear enhancement function as the voltage damping ratio enhancement term is used, based on the recommended critical damping value in control engineering (…). (≥0.7), the specific calculation formula is as follows: In the formula, The damping ratio is calculated using the logarithmic attenuation method of adjacent peaks on the frequency waveform. When When =0.7, =1; when When >0.7, >1; when When <0.7, <1.

[0083] Multiplying the static frequency steady-state evaluation result, the deviation suppression term, the settling time term, the frequency damping ratio enhancement term, and the active power steady-state evaluation result yields the dynamic frequency steady-state evaluation result DFSI of the grid-type converter under test. This embodiment employs a multiplicative fusion approach to ensure that performance degradation in any dimension can significantly reduce the overall index. The dynamic frequency steady-state evaluation result comprehensively quantifies the converter's static gain, peak rejection capability, recovery speed, oscillation damping characteristics, and energy sustainability under frequency disturbances, fully reflecting its support capability throughout the entire process from disturbance occurrence to stable recovery.

[0084] The above implementation constructs a deviation suppression term (inversely proportional to the maximum frequency deviation) based on the maximum frequency deviation. This feature quantifies the converter's ability to suppress frequency peak deviations: the smaller the maximum frequency deviation, the larger the deviation suppression term, reflecting the device's ability to effectively "block" excessive frequency drops or rises. Secondly, a settling time term (exponentially decaying with settling time) is constructed based on the settling time. This feature quantifies the speed of frequency recovery: the shorter the settling time, the larger the settling time term, and the exponential decay causes a sharp drop in the score of devices with slow recovery. Next, a frequency damping ratio enhancement term (linearly increasing with frequency damping ratio) is constructed based on the frequency waveform damping ratio. This feature, based on second-order system damping theory, excites the rapid calming of frequency oscillations, preventing the frequency from repeatedly crossing the rated value during recovery. Then, the static frequency evaluation result (reflecting steady-state gain), the deviation suppression term (reflecting peak suppression), the settling time term (reflecting recovery speed), the frequency damping ratio enhancement term (reflecting oscillation damping), and the functional quantity evaluation result (reflecting energy sustainability) are multiplied to obtain the dynamic frequency evaluation result.

[0085] In this embodiment, step 106 includes: Step 1061: Obtain the minimum value between the steady-state evaluation result of the non-functional quantity and the steady-state evaluation result of the functional quantity; Step 1062: Based on the state of charge of the grid-type converter under test, obtain the state of charge availability factor of the grid-type converter under test; wherein, the state of charge availability factor increases linearly with the state of charge and is zero when the state of charge is lower than a preset threshold; Step 1063: Multiply the minimum value by the state-of-charge availability factor to obtain the steady-state evaluation result of the grid-type converter under test.

[0086] In this embodiment, based on the dynamic support capabilities of voltage and frequency, the energy sustainability and SOC availability of the grid-type energy storage converter are further quantified over long time scales (seconds to minutes). The grid-type converter's steady-state evaluation result (CSI) is as follows: In the formula, SOC represents the state of charge of the grid-connected energy storage converter. An energy bottleneck cutoff method is adopted, meaning that if either active or reactive power fails to meet demand, the converter is removed from the grid, and the minimum value is used to achieve the "weakest link" effect.

[0087] The above implementation obtains the minimum value between the active and non-active energy assessment results, which is consistent with the physical constraints in the actual operation of the converter (for example, even if the reactive power reserve is sufficient, the converter cannot maintain frequency support if the active power is depleted). Secondly, the state-of-charge (SOC) availability factor is obtained based on the SOC (which increases linearly with SOC and becomes zero below a threshold). This feature reflects the actual available energy range of the energy storage system, conforming to the engineering constraints of the battery management system on the depth of discharge and upper limit of charging. Then, the minimum value is multiplied by the SOC availability factor to obtain the grid-connected steady-state assessment result. This feature combines the energy bottleneck with SOC availability, reflecting the energy margin required relative to the current disturbance. The SOC availability factor reflects the state of the energy storage system itself; the multiplication of the two truly characterizes the converter's sustainable grid-connected capability over a long timescale.

[0088] In this embodiment, step 107 includes: Step 1071: Based on the application scenario type of the grid-type converter under test, determine the first weight corresponding to the dynamic voltage steady-state evaluation result, the second weight corresponding to the dynamic frequency steady-state evaluation result, and the third weight corresponding to the grid-type steady-state evaluation result; Step 1072: Multiply the dynamic voltage steady-state evaluation result by the first weight, the dynamic frequency steady-state evaluation result by the second weight, and the grid-type steady-state evaluation result by the third weight, and then sum them to obtain the disturbance response test result of the grid-type converter under test.

[0089] The method for determining the evaluation weights of different application scenarios for each dimension in this embodiment specifically includes: For weak network scenarios: Based on the characteristics of low system short-circuit capacity and insufficient inertia, the highest proportion of dynamic voltage support weight and dynamic frequency support weight, and a lower proportion of network continuity weight are configured. For isolated scenarios: Based on the characteristics of the system operating independently of the main network and needing to cope with load fluctuations in an independent area, compared with weak network scenarios, the weight of dynamic voltage and dynamic frequency support is appropriately reduced, while the weight of network continuity is increased. For black start scenarios: Based on the stringent characteristics of the system needing to gradually wake up the de-energized grid and release energy over a long period of time, compared to islanded scenarios, the weights of dynamic voltage and dynamic frequency support are further reduced, while the weight of network continuity is increased to the highest proportion.

[0090] Specifically, the evaluation weights are: In the weak network scenario, the evaluation weights for dynamic voltage support capability. =0.45, weight for evaluating dynamic frequency support capability =0.45, weight for evaluating network sustainability. =0.10; In the islanded scenario, the evaluation weight for dynamic voltage support capability is... =0.40, weight for evaluating dynamic frequency support capability =0.40, weight for evaluating network sustainability. =0.20; In the black-start scenario, the evaluation weight for dynamic voltage support capability is... =0.35, weight for evaluating dynamic frequency support capability =0.35, weight for evaluating network sustainability. =0.30.

[0091] Based on the aforementioned weights, the disturbance response test results of the grid-type energy storage converter I.

[0092] The above implementation determines the first, second, and third weights based on the application scenario type of the grid-type converter under test. This feature allows for differentiated weight combinations for different scenarios such as weak grids, islanding, and black starts. Next, the dynamic voltage evaluation result is multiplied by the first weight, the dynamic frequency evaluation result by the second weight, and the grid steady-state evaluation result by the third weight, and then summed to obtain the disturbance response test result. This feature outputs a single comprehensive index, facilitating a direct comparison of the overall performance of different devices.

[0093] In this first embodiment, to verify the scientific validity, objectivity, and effectiveness of the testing method disclosed herein compared to existing technologies, the following comparative simulation examples are provided. Figure 2 , Figure 3 Perform quantitative analysis: Specifically, two grid-connected energy storage converters with the same rated capacity are set up, where device A is controlled by a virtual synchronous machine and device B is controlled by droop control. At a simulation time of 0.5 s, a frequency step sag disturbance of 0.2 Hz and a voltage step sag disturbance of 0.1 pu are applied to the system, respectively.

[0094] Limitations of existing technology evaluation methods, such as Figure 2 , Figure 3 As shown, after being disturbed, devices A and B undergo different dynamic processes, ultimately reaching the same steady-state target value. If the existing evaluation method, which only focuses on steady-state deviation, is used, the static support capability index scores of the two devices will be exactly the same, failing to identify the potential for high overshoot and severe oscillations generated by device B during the transient process.

[0095] The effectiveness of the test method disclosed herein is demonstrated as follows: Based on the waveform features extracted by the test method constructed according to this invention: For device A, its waveform is smooth with no significant overshoot, the settling time into the ±2% error band is extremely short, and all dynamic excitation terms are positive gains. Calculations using S206 and S306 yield a dynamic voltage support index (DVSI) of 1.20 and a dynamic frequency support index (DFSI) of 1.25. For device B, although its response is fast, it generates severe voltage and frequency overshoot, accompanied by low-frequency oscillations that significantly prolong the settling time, triggering overshoot penalties and an exponential decay mechanism. Calculations show its dynamic scores are DVSI = 0.50 and DFSI = 0.45.

[0096] In the aforementioned short-term verification scenario, since the long-term bottleneck of battery energy decay has not been reached, it can be assumed that the network sustainability index (CSI) of both devices remains at its initial full score, i.e., CSI = 1.00. Selecting the weak network application scenario in Table 1 and substituting it into the S501 comprehensive evaluation formula, the comprehensive score of device A is GS = 1.2025, and the comprehensive score of device B is GS = 0.5275.

[0097] As can be seen from the above quantitative calculations, when the traditional steady-state evaluation scores are exactly the same, the comprehensive evaluation index constructed by this invention successfully distinguishes and quantitatively classifies equipment A and equipment B with extremely significant differences. This result conclusively proves that the testing method of this application can comprehensively and accurately capture the true capabilities of grid-type converters, overcome the shortcomings of existing evaluation techniques that only consider steady-state effects, and possesses strong objective effectiveness and industrial application value.

[0098] On the other hand, refer to Figure 4 This embodiment also discloses a disturbance response testing system for a grid-type converter, including a disturbance module 401, a static evaluation module 402, an energy evaluation module 403, a dynamic voltage module 404, a dynamic frequency module 405, a grid evaluation module 406, and a response testing module 407.

[0099] The disturbance module 401 is used to acquire time-domain electrical quantity data of the grid-type converter under test under a preset disturbance sequence, so as to acquire the steady-state operating characteristic data and disturbance response characteristic data of the grid-type converter under test based on the time-domain electrical quantity data.

[0100] The static evaluation module 402 is used to obtain the static voltage steady-state evaluation results and static frequency steady-state evaluation results of the grid-type converter under test based on the operating steady-state characteristic data.

[0101] The energy assessment module 403 is used to obtain the non-functional steady-state assessment results and functional steady-state assessment results of the grid-type converter under test based on the time-domain electrical quantity data and the operating steady-state characteristic data.

[0102] The dynamic voltage module 404 is used to obtain the dynamic voltage steady-state evaluation result of the grid converter under test based on the static voltage steady-state evaluation result, the disturbance response characteristic data and the non-functional quantity steady-state evaluation result.

[0103] The dynamic frequency module 405 is used to obtain the dynamic frequency steady-state evaluation result of the grid-type converter under test based on the static frequency steady-state evaluation result, the functional quantity steady-state evaluation result, the disturbance response characteristic data, and the time-domain electrical quantity data.

[0104] The network evaluation module 406 is used to obtain the network steady-state evaluation result of the tested network converter based on the steady-state evaluation result of the non-functional quantity and the steady-state evaluation result of the functional quantity.

[0105] The response test module 407 is used to obtain the disturbance response test results of the grid-type converter under test based on the dynamic voltage steady-state evaluation results, the dynamic frequency steady-state evaluation results, and the grid-type steady-state evaluation results.

[0106] This embodiment discloses a disturbance response testing method and system for a grid-type converter. It sequentially constructs an evaluation index system including voltage support, frequency support, and other dimensions. Based on preset technical standards, it calculates the values ​​of each individual index, normalizes the index values, and introduces a dynamic weight allocation mechanism oriented towards application scenarios. Finally, it solves to obtain the comprehensive grid index of the grid-type energy storage converter, realizing the effective quantification and level evaluation of the overall support capability of the grid-type energy storage converter. Meanwhile, by constructing DVSI, DFSI, and CSI and ultimately merging them into GS, a multi-dimensional and integrated comprehensive evaluation of the voltage, frequency, and continuous support capabilities of grid-type energy storage converters is achieved. The system innovatively incorporates time-domain dynamic response characteristics (fast, stable, and accurate) into the evaluation system, which more realistically reflects the actual support performance of the equipment under disturbances, compensating for the shortcomings of existing methods that focus on steady-state conditions. A dynamic weight allocation mechanism oriented towards typical application scenarios (weak grid, islanding, black start) is introduced, making the evaluation results more aligned with actual engineering needs and guiding equipment selection and strategy optimization. Based on port electrical quantity black-box testing, which does not rely on internal equipment parameters, a unified performance benchmark and acceptance standard is provided for grid-type converters from different manufacturers and with different control strategies.

[0107] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. A disturbance response testing method for a grid-type converter, characterized in that, include: The time-domain electrical quantity data of the grid-type converter under test is obtained under a preset disturbance sequence, so as to obtain the steady-state characteristic data and disturbance response characteristic data of the grid-type converter under test based on the time-domain electrical quantity data; Based on the operating steady-state characteristic data, obtain the static voltage steady-state evaluation results and the static frequency steady-state evaluation results of the grid converter under test; Based on the time-domain electrical quantity data and the operating steady-state characteristic data, obtain the non-functional steady-state evaluation results and functional steady-state evaluation results of the grid-type converter under test; The dynamic voltage steady-state evaluation results of the grid converter under test are obtained based on the static voltage steady-state evaluation results, the disturbance response characteristic data, and the non-functional quantity steady-state evaluation results. The dynamic frequency steady-state evaluation result of the grid-type converter under test is obtained based on the static frequency steady-state evaluation result, the functional quantity steady-state evaluation result, the disturbance response characteristic data, and the time-domain electrical quantity data. The steady-state evaluation results of the grid-type converter under test are obtained based on the steady-state evaluation results of the non-functional quantities and the steady-state evaluation results of the functional quantities. The disturbance response test results of the grid-type converter under test are obtained based on the dynamic voltage steady-state evaluation results, the dynamic frequency steady-state evaluation results, and the grid-type steady-state evaluation results.

2. The disturbance response testing method for a grid-type converter according to claim 1, characterized in that, The step of acquiring time-domain electrical quantity data of the grid-type converter under test under a preset disturbance sequence, and then acquiring the steady-state operating characteristic data and disturbance response characteristic data of the grid-type converter under test based on the time-domain electrical quantity data, includes: Obtain the converter model corresponding to the grid-type converter under test and the equivalent power grid model connected to the converter model; The equivalent power grid model is connected to the converter model through a common connection point, and a preset disturbance sequence is applied at the common connection point to obtain the time-domain electrical quantity data of the grid-type converter under test; wherein, the time-domain electrical quantity data includes the power grid time-series electrical quantity at the common connection point and the converter time-series electrical quantity at the AC output port of the converter model; The disturbance response characteristic data of the grid-type converter under test are obtained based on the time-series electrical quantities of the power grid, and the steady-state operating characteristic data of the grid-type converter under test are obtained based on the time-series electrical quantities of the power grid and the time-series electrical quantities of the converter.

3. The disturbance response testing method for a grid-type converter according to claim 2, characterized in that, The power grid time-series electrical quantities include the power grid voltage time-series waveform, the power grid frequency time-series waveform, and the power grid frequency change rate time-series waveform; the converter time-series electrical quantities include the converter active power time-series waveform and the converter reactive power waveform. The process of obtaining disturbance response characteristic data of the grid-connected converter under test based on the grid time-series electrical quantities and obtaining steady-state operating characteristic data of the grid-connected converter under test based on the grid time-series electrical quantities and the converter time-series electrical quantities includes: The disturbance response characteristic data of the grid-type converter under test are obtained based on the grid voltage time-series waveform or the grid frequency time-series waveform; wherein, the disturbance response characteristic data includes response time, overshoot, settling time and damping ratio; The voltage deviation is obtained based on the power grid voltage timing waveform, and the frequency deviation is obtained based on the power grid frequency timing waveform; The frequency change rate is obtained from the time-series waveform of the power grid frequency change rate, and the active power change is obtained from the time-series waveform of the converter active power. The reactive power change is obtained based on the reactive power waveform of the converter, and the voltage deviation, frequency deviation, frequency change rate, active power change, and reactive power change are used as the steady-state characteristic data of the grid-type converter under test.

4. A disturbance response testing method for a grid-type converter according to any one of claims 1-3, characterized in that, The step of obtaining the static voltage steady-state evaluation results and static frequency steady-state evaluation results of the grid-type converter under test based on the operating steady-state characteristic data includes: Obtain the rated capacity, rated voltage, and rated frequency of the grid-type converter under test; Based on the rated capacity, the rated voltage, and the voltage deviation and reactive power change in the operating steady-state characteristic data, the reactive power response ratio of the grid-type converter under test to the voltage deviation is obtained, and the reactive power response ratio is used as the static voltage steady-state evaluation result. Based on the rated capacity, the rated frequency, and the active power change and frequency deviation in the steady-state characteristic data, the first active power response ratio of the grid-type converter under test to the frequency deviation is obtained. Based on the rated capacity, the rated frequency, and the active power change and frequency change rate in the steady-state characteristic data, obtain the second active power response ratio of the grid-type converter under test to the frequency change rate; Norm fusion is performed on the first active response ratio and the second active response ratio to obtain the static frequency steady-state evaluation result.

5. A disturbance response testing method for a grid-type converter according to any one of claims 1-3, characterized in that, The step of obtaining the non-functional steady-state evaluation results and functional steady-state evaluation results of the grid-type converter under test based on the time-domain electrical quantity data and the operating steady-state characteristic data includes: Based on the converter reactive power waveform in the time-domain electrical quantity data, obtain the first reactive power quantity of the grid-type converter under test; The state of charge, battery capacity, linear bus voltage, and power efficiency of the grid-type converter under test are obtained, so as to obtain the second non-functional quantity and the first functional quantity of the grid-type converter under test based on the state of charge, the battery capacity, the linear bus voltage, and the power efficiency. Obtain the first ratio of the second reactive power to the first reactive power, and obtain the first minimum value between the first ratio and a preset energy threshold, so as to use the first minimum value as the steady-state evaluation result of the reactive power of the grid-type converter under test. Based on the converter active power timing waveform in the time-domain electrical quantity data, the second active power quantity of the grid-type converter under test is obtained. Obtain a second ratio between the second functional quantity and the first functional quantity, and obtain a second minimum value between the second ratio and a preset energy threshold, so as to use the second minimum value as the steady-state evaluation result of the functional quantity of the grid-type converter under test.

6. The disturbance response testing method for a grid-type converter according to claim 5, characterized in that, The step of obtaining the dynamic voltage steady-state evaluation result of the grid-type converter under test based on the static voltage steady-state evaluation result, the disturbance response characteristic data, and the non-functional quantity steady-state evaluation result includes: Based on the response time in the disturbance response characteristic data, the response speed term is obtained; wherein, the response speed term is inversely proportional to the response time. Based on the overshoot in the disturbance response characteristic data, a stationarity suppression term is obtained; wherein the stationarity suppression term decays exponentially with the increase of the overshoot. Based on the damping ratio in the disturbance response characteristic data, a damping ratio enhancement term is obtained; wherein, the damping ratio enhancement term increases linearly with the increase of the damping ratio; Multiply the static voltage steady-state evaluation result, the response speed term, the stability suppression term, the damping ratio enhancement term, and the non-functional quantity steady-state evaluation result to obtain the dynamic voltage steady-state evaluation result of the grid-type converter under test.

7. The disturbance response test method for a grid-type converter according to claim 5, characterized in that, The process of obtaining the dynamic frequency steady-state evaluation result of the grid-type converter under test based on the static frequency steady-state evaluation result, the functional quantity steady-state evaluation result, the disturbance response characteristic data, and the time-domain electrical quantity data includes: The maximum frequency deviation after disturbance is extracted from the power grid frequency time-series waveform in the time-domain electrical quantity data, and a deviation suppression term is constructed based on the maximum frequency deviation; wherein, the deviation suppression term is inversely proportional to the maximum frequency deviation; Based on the settling time in the disturbance response characteristic data, a settling time term is constructed; wherein, the settling time term decays exponentially as the settling time increases; Based on the frequency damping ratio of the power grid frequency time-series waveform, a frequency damping ratio enhancement term is constructed; wherein, the frequency damping ratio enhancement term increases linearly with the increase of the frequency damping ratio; The dynamic frequency steady-state evaluation result of the grid-type converter under test is obtained by multiplying the static frequency steady-state evaluation result, the deviation suppression term, the adjustment time term, the frequency damping ratio enhancement term, and the functional quantity steady-state evaluation result.

8. The disturbance response testing method for a grid-type converter according to claim 1, characterized in that, The step of obtaining the grid-connected steady-state evaluation result of the tested grid-connected converter based on the non-functional steady-state evaluation result and the functional steady-state evaluation result includes: Obtain the minimum value between the steady-state evaluation result of the non-functional quantity and the steady-state evaluation result of the functional quantity; Based on the state of charge of the grid-connected converter under test, the state of charge availability factor of the grid-connected converter under test is obtained; wherein, the state of charge availability factor increases linearly with the state of charge and is zero when the state of charge is lower than a preset threshold; Multiplying the minimum value by the state-of-charge availability factor yields the steady-state evaluation result of the grid-type converter under test.

9. The disturbance response test method for a grid-type converter according to claim 1, characterized in that, The step of obtaining the disturbance response test results of the grid-type converter under test based on the dynamic voltage steady-state evaluation results, the dynamic frequency steady-state evaluation results, and the grid-type steady-state evaluation results includes: Based on the application scenario type of the grid-type converter under test, determine the first weight corresponding to the dynamic voltage steady-state evaluation result, the second weight corresponding to the dynamic frequency steady-state evaluation result, and the third weight corresponding to the grid steady-state evaluation result. The disturbance response test result of the grid-type converter under test is obtained by multiplying the dynamic voltage steady-state evaluation result by the first weight, the dynamic frequency steady-state evaluation result by the second weight, and the grid-type steady-state evaluation result by the third weight.

10. A disturbance response testing system for a grid-type converter, characterized in that, It includes a disturbance module, a static evaluation module, an energy evaluation module, a dynamic voltage module, a dynamic frequency module, a network evaluation module, and a response testing module; The disturbance module is used to acquire time-domain electrical quantity data of the grid-type converter under test under a preset disturbance sequence, so as to acquire the steady-state operating characteristic data and disturbance response characteristic data of the grid-type converter under test based on the time-domain electrical quantity data; The static evaluation module is used to obtain the static voltage steady-state evaluation result and the static frequency steady-state evaluation result of the grid-type converter under test based on the operating steady-state characteristic data. The energy assessment module is used to obtain the non-functional steady-state assessment results and functional steady-state assessment results of the grid-type converter under test based on the time-domain electrical quantity data and the operating steady-state characteristic data. The dynamic voltage module is used to obtain the dynamic voltage steady-state evaluation result of the grid converter under test based on the static voltage steady-state evaluation result, the disturbance response characteristic data and the non-functional quantity steady-state evaluation result. The dynamic frequency module is used to obtain the dynamic frequency steady-state evaluation result of the grid-type converter under test based on the static frequency steady-state evaluation result, the functional quantity steady-state evaluation result, the disturbance response characteristic data, and the time-domain electrical quantity data. The network evaluation module is used to obtain the network steady-state evaluation result of the tested network converter based on the non-functional steady-state evaluation result and the functional steady-state evaluation result. The response test module is used to obtain the disturbance response test results of the grid-type converter under test based on the dynamic voltage steady-state evaluation results, the dynamic frequency steady-state evaluation results, and the grid-type steady-state evaluation results.

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