Method, System and Equipment for Verifying Electromagnetic Transient Simulation Model of Battery Energy Storage System on ADPSS Platform

Abstract

The method, system and device for verifying the electromagnetic transient simulation model of the ADPSS platform battery energy storage system belong to the technical field of electromagnetic transient simulation of battery energy storage systems in power systems. In order to solve the problem that the current non-verification of the ADPSS simulation model affects the simulation effect based on the ADPSS simulation model. When verifying the main circuit of the present invention, based on the branch resistance R of the MATLAB platform z and the branch resistance X z , verify the excitation branch resistance #imgabs0# and the magnetic branch reactance #imgabs1# of the ADPSS model. When verifying the control circuit, set the limit parameter of the PI controller of ADPSS to infinity, and add a separate limit element at the output port of the PI controller. The parameter setting of the limit element is consistent with the MATLAB platform; when verifying the measurement circuit, according to the ON and OFF points of the hysteresis comparator parameters of the MATLAB platform, set the interval average value M=(ON + OFF) / 2 and the interval margin HY=(ON - OFF) / 2 of the hysteresis comparator of the ADPSS platform.

Description

Technical Field

[0001] The present invention belongs to the technical field of electromagnetic transient simulation of battery energy storage systems in power systems, and particularly relates to a method, system and device for high-precision electromagnetic transient modeling and simulation of battery energy storage systems. Background Technique

[0002] Currently, with the progress of technology, the grid-connected scale of battery energy storage power stations is continuously expanding, and extensive theoretical research and engineering applications have been obtained in different application scenarios in the power grid. In order to study the dynamic response parameters of battery energy storage systems and their impact on power grid stability, and to improve the control and protection of energy storage controllers, it is necessary to establish a simulation model consistent with the actual response characteristics of the energy storage system.

[0003] Regarding the modeling and simulation analysis of battery energy storage, existing research is mostly based on foreign simulation platforms. For example:

[0004] 1. Foreign simulation platforms such as MATLAB, PSS / E, and PowerWord have integrated widely used general electromechanical models and have been widely applied.

[0005] 2. Qiao Zhijie et al. published "Research on Large-Scale Energy Storage Control Strategies for Power System Stability Improvement", High Voltage Apparatus, 2022, 58(12): 75-84. This article considered the state of charge of the energy storage system and the power system load demand, established a secondary frequency modulation model of the energy storage system, and verified the superiority of this model compared with other models using MATLAB / Simulink.

[0006] 3. Gan Wei et al. published "Multi-Scale and Multi-Index Energy Storage Configuration for Wind Farm Output Smoothing", Automation of Electric Power Systems, 2019, 43(9): 92-98. This article accurately solved the proposed multi-scale and multi-index energy storage configuration model using the MATLAB simulation platform.

[0007] 4. Zhang Jiaqi et al. published "Electromagnetic Transient Modeling Method of Lithium-Ion Battery Energy Storage for Fault Characteristic Analysis", Automation of Electric Power Systems, 2023, 47(07): 166-173. This article analyzed the fault characteristics of the battery energy storage system based on PSCAD / EMTDC and established an electromagnetic transient simulation model applicable to symmetric and asymmetric voltage fault characteristics.

[0008] In summary, the current modeling research on battery energy storage systems is mostly customized for foreign mainstream simulation platforms. However, with the promotion of the localization process, more and more practical engineering and academic research are carried out on the domestic ADPSS simulation platform with independent intellectual property rights. However, there are differences in model structure, parameters, and usage methods between domestic and foreign software, which limit the application selectivity of different simulation platforms. At the same time, due to the differences in model structure, parameters, and usage methods between domestic and foreign software, it has caused certain usage obstacles for ADPSS users, making it impossible to determine the reliability benchmark of the simulation results of the simulation model based on ADPSS, affecting the simulation effect of the simulation model based on ADPSS. Currently, there is a lack of a high-precision modeling method for the research of battery energy storage systems on the ADPSS platform. Summary of the Invention

[0009] The present invention aims to solve the problem that the lack of verification of the ADPSS simulation model affects the simulation effect of the simulation model based on ADPSS.

[0010] An electromagnetic transient simulation model verification method for a battery energy storage system on the ADPSS platform, which respectively constructs simulation models of the battery energy storage system based on the ADPSS platform and the MATLAB platform. The simulation model of the battery energy storage system includes a main circuit, a control circuit, and a measurement circuit;

[0011] The main circuit corresponding to the simulation model of the battery energy storage system includes an energy storage battery model, a capacitor, an inverter, a filter, and a step-up transformer. Among them, the inverter is the bridge for the energy storage system to connect to the grid. The DC side of the inverter includes a battery model and a capacitor, and the DC capacitor is connected in parallel with the battery model. The AC side of the inverter includes a filter and a step-up transformer. The step-up transformer uses a three-phase two-winding transformer. The low-voltage side of the transformer is the energy storage side, and the high-voltage side of the transformer is the grid side. The output power of the energy storage side is fed into the collector network through the step-up transformer;

[0012] The control circuit includes a steady-state control circuit, a low-voltage ride-through control circuit, and a high-voltage ride-through control circuit. The abc three-phase voltages on the AC side of the inverter are generated through the control circuit and transmitted to the inverter. The steady-state control circuit adopts a double-loop decoupling control, and the double-loop decoupling control includes a power outer loop and a current inner loop, and the double-loop decoupling control realizes independent control of active and reactive power. The active power control and reactive power control of the low-voltage ride-through control circuit both adopt a single-current inner loop control structure. The active power control of the high-voltage ride-through control circuit continues to use the steady-state double-loop control circuit for active power, and the reactive power control adopts a single-current inner loop control structure;

[0013] The measurement circuit is responsible for obtaining the voltage and output current from the grid connection point of the energy storage system, performing coordinate system transformation and power calculation on the obtained voltage and current to obtain the electrical quantities required for control; comparing the positive sequence voltage u at the grid connection point in the electrical quantities required for control with the voltage thresholds for entering and exiting low / high ride-through of active and reactive power to determine the voltage ride-through flag bit, and the flag bit is used to control the switching of the steady-state and low / high ride-through control states of the circuit; the comparison between the positive sequence voltage u and the voltage threshold is performed using the hysteresis comparator module in the ADPSS platform and the basic module library of the MATLAB platform;

[0014] For the main circuit, control circuit and measurement circuit, taking the MATLAB platform module as the benchmark, the ADPSS simulation model is checked;

[0015] Main circuit check: For the three-phase two-winding transformer on both platforms, based on the branch resistance R z and branch resistance X z set on the MATLAB platform, the parameters of the transformer module in the ADPSS model are set: the exciting branch resistance of the transformer the exciting branch reactance of the transformer

[0016] Control circuit check: Conduct a structural check on the PI controllers with differences. Set the limit parameters of the PI controller in ADPSS to infinity, and add a separate limit element at the output port of the PI controller. The parameter settings of the limit element are the same as the limit parameter settings of the PI controller on the MATLAB platform;

[0017] Measurement circuit check: Conduct a parameter check on the hysteresis comparators with differences. According to the parameter opening point ON and closing point OFF of the hysteresis comparator on the MATLAB platform, set the interval average value M and interval margin HY of the hysteresis comparator on the ADPSS platform:

[0018] Furthermore, the battery model on the DC side of the main circuit corresponding to the battery energy storage system simulation model is based on the Rint model, and the constant voltage source in the Rint model is changed to a controlled voltage source.

[0019] Furthermore, in the charging and discharging modes, the magnitudes of the voltage E of the controlled voltage source of the battery model are f 1 and f 2 respectively:

[0020]

[0021]

[0022] In the formula: i is the battery current; i s 、i *They are the integrated current of the battery current and the filtered current of the battery current respectively; A is the voltage drop in the exponential region; B is the time constant in the exponential region; K is the polarization voltage; E 0 is the nominal voltage.

[0023] Furthermore, the filter on the AC side of the converter uses an LC-type filter.

[0024] Furthermore, the electrical quantities required for the control include: the d-axis component e of the voltage on the low-voltage side of the transformer d , the q-axis component e of the voltage on the low-voltage side of the transformer q , the active current i d , the reactive current i q , the positive-sequence voltage u at the grid connection point, the active power P, and the reactive power Q.

[0025] Furthermore, during the process of coordinate transformation and power calculation of the acquired voltage and current, the dq-to-abc module in the basic module library of the ADPSS platform and the MATLAB platform is used for coordinate transformation.

[0026] Furthermore, during the process of coordinate transformation and power calculation of the acquired voltage and current, the instantaneous power calculation module in the basic module library of the ADPSS platform and the MATLAB platform is used for power calculation.

[0027] An electromagnetic transient simulation model verification system for a battery energy storage system on the ADPSS platform, the system verifies the simulation model of the battery energy storage system constructed based on the ADPSS platform and the MATLAB platform;

[0028] The simulation model of the battery energy storage system includes a main circuit, a control circuit, and a measurement circuit;

[0029] The main circuit corresponding to the simulation model of the battery energy storage system includes an energy storage battery model, a capacitor, a converter, a filter, and a step-up transformer; among them, the converter is the bridge for the energy storage system to connect to the grid. The DC side of the converter includes a battery model and a capacitor, and the DC capacitor is connected in parallel with the battery model; the AC side of the converter includes a filter and a step-up transformer; the step-up transformer uses a three-phase two-winding transformer. The low-voltage side of the transformer is the energy storage side, and the high-voltage side of the transformer is the grid side. The output power of the energy storage side is fed into the collector network through the step-up transformer;

[0030] The control circuit includes a steady-state control circuit, a low-voltage ride-through control circuit, and a high-voltage ride-through control circuit. The control circuit generates the abc three-phase voltages on the AC side of the converter and transmits them to the converter. The steady-state control circuit adopts double-loop decoupling control, which includes a power outer loop and a current inner loop. The double-loop decoupling control realizes independent control of active and reactive power. The active power control and reactive power control of the low-voltage ride-through control circuit both adopt a single-current inner loop control structure. The active power control of the high-voltage ride-through control circuit continues to use the steady-state double-loop control circuit for active power, and the reactive power control adopts a single-current inner loop control structure.

[0031] The measurement circuit is responsible for obtaining the voltage and output current from the grid connection point of the energy storage system, performing coordinate transformation and power calculation on the obtained voltage and current to obtain the electrical quantities required for control. The positive-sequence voltage u at the grid connection point among the electrical quantities required for control is compared with the voltage thresholds for entering and exiting low / high ride-through of active and reactive power to determine the voltage ride-through flag bit. The flag bit is used to control the switching of the steady-state and low / high ride-through control states of the control circuit. The comparison between the positive-sequence voltage u at the grid connection point and the voltage threshold uses the hysteresis comparator module in the ADPSS platform and the basic module library of the MATLAB platform.

[0032] The system includes a main circuit verification unit, a control circuit verification unit, and a measurement circuit verification unit. Among them,

[0033] Main circuit verification unit: For the three-phase two-winding transformer on the two platforms, based on the magnitudes of the branch resistance R z and branch reactance X z set on the MATLAB platform, the parameters of the transformer module in the ADPSS model are set: the exciting branch resistance of the transformer the exciting branch reactance of the transformer

[0034] Control circuit verification unit: Conduct structural verification on the PI controllers with differences. Set the limit parameters of the PI controller in ADPSS to infinity, and add a separate limiting element at the output port of the PI controller. The parameter settings of the limiting element are the same as the limit parameter settings of the PI controller on the MATLAB platform.

[0035] Measurement circuit verification unit: Conduct parameter verification on the hysteresis comparators with differences. According to the ON point and OFF point of the hysteresis comparator parameters on the MATLAB platform, set the interval average value M and interval margin HY of the hysteresis comparator on the ADPSS platform:

[0036] A computer storage medium stores at least one instruction in the storage medium, and the at least one instruction is loaded and run by a processor for an electromagnetic transient simulation model verification system of a battery energy storage system on an ADPSS platform.

[0037] An electromagnetic transient simulation model verification device for a battery energy storage system of an ADPSS platform, the device includes a processor and a memory, at least one instruction is stored in the memory, and the at least one instruction is loaded and run by the processor to implement the electromagnetic transient simulation model verification system for the battery energy storage system of the ADPSS platform.

[0038] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0039] Based on the domestic new generation simulation platform of ADPSS, the present invention conducts research on the electromagnetic transient modeling and simulation of the battery energy storage system, and takes the simulation of the mature MATLAB platform as a benchmark, and proposes a verification method for the simulation model of the ADPSS platform, which ensures the simulation consistency between the simulation results of the simulation model of ADPSS and other platforms, and can improve the simulation accuracy of the simulation model of the battery energy storage system of the ADPSS platform. Description of the Drawings

[0040] Figure 1 It is the structure diagram of the simulation model of the battery energy storage system.

[0041] Figure 2 It is the single-phase equivalent circuit diagram of the three-phase two-winding transformer of the ADPSS and MATLAB platforms, where (a) corresponds to the ADPSS platform and (b) corresponds to the MATLAB platform.

[0042] Figure 3 It is the internal structure diagram of the PI controller of the ADPSS and MATLAB platforms, where (a) corresponds to the ADPSS platform and (b) corresponds to the MATLAB platform.

[0043] Figure 4 It is the principle of the hysteresis comparator of the ADPSS and MATLAB platforms, where (a) corresponds to the ADPSS platform and (b) corresponds to the MATLAB platform.

[0044] Figure 5 It is the structure diagram of the PI controller after verification of the ADPSS platform.

[0045] Figure 6 It is the comparison diagram of the voltage fault transient response curves corresponding to the fault voltage of 0.2 p.u.

[0046] Figure 7 It is the comparison diagram of the voltage fault transient response curves corresponding to the fault voltage of 0.5 p.u.

[0047] Figure 8 It is the comparison diagram of the voltage fault transient response curves corresponding to the fault voltage of 1.25 p.u.

[0048] Figure 9It is a comparison diagram of voltage fault transient response curves corresponding to a fault voltage of 1.3 p.u.

[0049] Figure 10 It is a comparison diagram of response deviations between the ADPSS model and the manufacturer's model before and after verification corresponding to a fault voltage of 0.5 p.u.

[0050] Figure 11 It is a comparison diagram of response deviations between the ADPSS model and the manufacturer's model before and after verification corresponding to a fault voltage of 1.25 p.u.

[0051] Figure 12 It is a schematic diagram of the ADPSS and MATLAB characteristics corresponding to the main circuit.

[0052] Figure 13 It is a schematic diagram of the ADPSS and MATLAB characteristics corresponding to the control circuit.

[0053] Figure 14 It is a schematic diagram of the ADPSS and MATLAB characteristics corresponding to the measurement circuit. Specific implementation manner

[0054] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0055] The present invention aims to solve the problem that the existing electromagnetic transient modeling and simulation research of energy storage systems lacks the application of domestic simulation platforms, and thus provides a method for verifying the ADPSS platform simulation model based on the MATLAB platform to achieve high-precision electromagnetic transient modeling and simulation of the battery energy storage system on the ADPSS platform, so as to facilitate the application and promotion of domestic software in the research of energy storage system simulation technology. The present invention mainly focuses on the simulation accuracy of the battery energy storage system simulation model for the whole process of low and high voltage fault ride-through. Through the verification of the simulation model, a high-precision electromagnetic transient simulation model of the battery energy storage system on the ADPSS platform is constructed. The following is an explanation in conjunction with specific implementation manners. Specific implementation manner one:

[0057] This implementation manner is a method for verifying the electromagnetic transient simulation model of the battery energy storage system on the ADPSS platform, including the following steps:

[0058] S1. Respectively construct simulation models of the battery energy storage system based on the ADPSS platform and the MATLAB platform.

[0059] The simulation model of the present invention is divided into three parts: the main circuit, the control circuit, and the measurement circuit. The model structure is as Figure 1 shown.

[0060] 1) Main circuit

[0061] The typical structure of the main circuit of the battery energy storage unit includes an energy storage battery model, a capacitor, a converter, a filter, and a step-up transformer. Among them, the converter is the bridge for the energy storage system to connect to the grid. The DC side of the converter includes a battery model and a capacitor, and the AC side of the converter includes a filter and a step-up transformer.

[0062] The capacitor on the DC side uses a DC capacitor module. The DC capacitor is connected in parallel with the battery model to effectively suppress the voltage fluctuation on the DC side of the energy storage system. The battery model on the DC side is based on the Rint model. The constant voltage source in the Rint model is changed to a controlled voltage source E to reflect the characteristic differences of the battery under different operating conditions (this Rint model is a basic module in the Simulink model library of MATLAB software). In the charging and discharging modes, the magnitudes of the voltage E of the controlled voltage source of the energy storage battery model are f 1 and f 2 respectively:

[0063]

[0064]

[0065] where: i is the battery current; i s , i * are the integral current of the battery current and the filtered current of the battery current respectively; A is the voltage drop in the exponential region; B is the time constant in the exponential region; K is the polarization voltage; E 0 is the nominal voltage.

[0066] The two-level converter is a classic converter form and is the most widely used converter in energy storage. To reflect generality, this type of converter is used for simulation in the present invention. The filter on the AC side of the converter uses a typical LC-type filter. This filter includes a grid-side filtering inductor, a grid-side filtering resistor, a filtering capacitor, and a capacitor branch resistor, which can effectively eliminate harmonics and improve the power quality. The step-up transformer uses a three-phase two-winding transformer. The low-voltage side of the transformer is the energy storage side, and the high-voltage side of the transformer is the grid side. The output power of the energy storage side is fed into the collector network through the step-up transformer.

[0067] 2) Control circuit

[0068] The control circuit includes a steady-state control circuit, a low-voltage ride-through control circuit, and a high-voltage ride-through control circuit. The abc three-phase voltages on the AC side of the converter are generated through the control circuit and transmitted to the converter.

[0069] The steady-state control circuit constructed by the present invention adopts the widely used double-loop decoupling control to achieve independent control of active and reactive power, including a power outer loop and a current inner loop, as shown in Equations (3) and (4) respectively. The active power control method is as follows: the active power reference value P ref is subtracted from the active power P and then adjusted by the PI controller of the power outer loop to obtain the active current reference value i dref , i dref is subtracted from the active current i d and then adjusted by the PI controller of the current inner loop. The output quantity introduces a feed-forward compensation term ωLi q related to the reactive current i 0 i q (ω is the system angular frequency, L 0 is the inductor of the grid-side filter) and the d-axis component e d of the low-voltage side voltage of the transformer to obtain the d-axis component of the required converter AC-side voltage; the reactive power control method is as follows: the reactive power reference value Q ref is subtracted from the reactive power Q and then adjusted by the PI controller of the power outer loop to obtain the reactive current reference value i qref , i qref is subtracted from the reactive current i q and then adjusted by the PI controller of the current inner loop. The output quantity introduces the feed-forward compensation terms ωLi 0 i d and the q-axis component e q of the low-voltage side voltage of the transformer to obtain the q-axis component of the required converter AC-side voltage. Finally, the obtained d-axis component and q-axis component of the converter AC-side voltage are as follows:

[0070]

[0071] In the formula, k op , k oi are respectively the proportional coefficient and the integral coefficient of the PI regulator of the power outer loop.

[0072]

[0073] In the formula, v d , v q are respectively the d-axis component and the q-axis component of the converter AC-side voltage in the dq coordinate system; k p , k i are respectively the proportional coefficient and the integral coefficient of the PI regulator of the current inner loop.

[0074] For both the active power control and reactive power control of the low-voltage ride-through control circuit constructed in the present invention, a single-current inner-loop control structure and a current command calculation formula are adopted. The single-current inner-loop control structure means that when the energy storage converter enters the low-ride-through control, the power outer-loop in the steady-state controller is deactivated, and only the current inner-loop is retained. The active current reference value i dref and the reactive current reference value i qref obtained from the current command calculation formula are directly connected to the current inner-loop for control. During the low-ride-through period, the current command calculation formula refers to the "Electrochemical Energy Storage Power Station Model Parameter Test Procedure - Draft for Comment", as shown in Equations (5) and (6).

[0075] Equation (5) is the calculation formula for the low-ride-through control strategy of active current and reactive current:

[0076]

[0077] In the formula, k 1_Id_LV , k 2_Id_LV , I dset_LV are the calculation coefficients for the low-ride-through active current; u is the positive-sequence voltage at the energy storage grid connection point; I d0 is the initial active current; k 1_Iq_LV , k 2_Iq_LV , I qset_LV are the calculation coefficients for the low-ride-through reactive current; U Lin is the voltage threshold for reactive power to enter the low-ride-through; I q0 is the initial reactive current.

[0078] Equation (6) is the current limiting calculation formula, and the limiting method adopts reactive power priority control. The maximum reactive current I qmax , the minimum reactive current I qmin , the maximum active current I dmax and the minimum active current I dmin are calculated as follows:

[0079]

[0080] In the formula, I qmax_set , I qmin_set are the maximum and minimum setting values of the reactive current respectively; I max is the maximum current.

[0081] For the active power control of the high-voltage ride-through control circuit constructed in the present invention, the steady-state double closed-loop control circuit for active power is continued to be used, and the reactive power control adopts a single-current inner-loop control structure and a current command calculation formula. The single-current inner-loop control structure means that when the energy storage converter enters the high-ride-through control, the power outer-loop for reactive power control in the steady-state controller is deactivated, and only the current inner-loop is retained. The reactive current reference value i qrefThe access current inner loop is used for control. During the high-ride-through period, the calculation formula of the reactive current command refers to the "Regulations on Model Parameter Testing of Electrochemical Energy Storage Power Stations - Draft for Comment", as shown in Equation (7) and Equation (6).

[0082] Equation (7) is the calculation formula for the active current reference value that continues to use the steady-state double closed-loop control for active power and the calculation formula for the reactive current high-ride-through control strategy:

[0083]

[0084] In the formula, k 1_Iq_HV , k 2_Iq_HV , I qset_HV are the calculation coefficients for the high-ride-through reactive current; U Hin is the voltage threshold for reactive power to enter the low-ride-through state.

[0085] Equation (6) is the current limit calculation formula. Similar to the current during the low-ride-through period, the current during the high-ride-through period also has an amplitude limit.

[0086] 3) Measuring circuit

[0087] The measuring circuit is responsible for obtaining the voltage and output current from the grid connection point of the energy storage system, performing coordinate transformation and power calculation on the obtained voltage and current to obtain the electrical quantities required for control. The electrical quantities required for control include: e d , e q , i d , i q , u, P, Q; comparing the obtained positive-sequence voltage u at the grid connection point with the voltage thresholds for active and reactive power to enter and exit the low / high-ride-through states to judge the voltage crossing flag bit. The flag bit is used to control the switching of the steady-state and low / high-ride-through control states of the circuit. The coordinate transformation is implemented using the dq-to-abc module in the platform basic module library, the power calculation is implemented using the instantaneous power calculation module in the platform basic module library, and the comparison between the positive-sequence voltage u at the grid connection point and the voltage threshold is implemented using the hysteresis comparator module in the platform basic module library.

[0088] S2. Obtain the manufacturer's test response data under the standard test conditions of low and high voltage faults using the battery energy storage unit instruction manual or the manufacturer's encapsulated model, as well as the parameters of the main circuit, control circuit, and measuring circuit of the simulation model of the battery energy storage system in step S1; input the obtained parameters into the simulation model built on the ADPSS and MATLAB platforms in step S1, and perform tests on the simulation model under the standard test conditions of low and high voltage faults to obtain the response data.

[0089] S3. Propose the mapping relationship between the module differences and characteristic differences between the ADPSS platform and the MATLAB platform.

[0090] Given that the deviation between the MATLAB simulation model response data and the manufacturer's test response data is significantly smaller than the deviation between the ADPSS simulation model response data and the manufacturer's test response data, taking the MATLAB platform as the benchmark, analyze the differences in the response characteristics between the ADPSS platform and the MATLAB platform from two aspects: steady-state characteristics and transient characteristics. Further, compare and analyze the differences between the basic sub-modules that make up the main circuit, control circuit, and measurement circuit of the simulation models of the two platforms:

[0091] There are differences in the single-phase equivalent circuits used to encapsulate parameter calculations in the transformer module of the main circuit. For example, Figure 2 As shown, in the equivalent circuit of the ADPSS transformer encapsulation module, the coupling branch between the two-winding resistance and inductance adopts the RL series form. The branch resistance and branch reactance are represented by R m and X m respectively. Its single-phase equivalent circuit is as shown in Figure 2 (a) in; In the equivalent circuit of the MATLAB / SIMULINK transformer encapsulation module, the coupling branch between the two-winding resistance and inductance adopts the RL parallel form. The branch resistance and branch reactance are represented by R z and X z respectively. Its single-phase equivalent circuit is as shown in Figure 2 (b) in. Due to the different internal encapsulations of the transformers in the two simulation platforms, if the same values are input when setting the parameters of the module, it will cause differences in the port voltages of the simulation models, thereby causing differences in the steady-state characteristics between the two simulation models.

[0092] The control circuit mainly includes basic algebraic operation elements and PI controllers. The PI controller is an encapsulated element, and its internal structure is as shown in Figure 3 . ΔX and Y are the input signal and output signal of the PI controller respectively; Y max and Y min are the maximum and minimum limits of the PI controller respectively; k cp is the proportional coefficient of the PI controller; T is the time coefficient of the PI controller on the ADPSS platform; k i is the integral coefficient of the PI controller on the MATLAB platform, and k i is the reciprocal of T, that is The internal structure of the PI controller in the ADPSS platform is as follows: the signal obtained by integrating the input signal is limited in amplitude, and the limited-amplitude signal is added to the signal obtained by passing the input signal through the proportional link to obtain the output signal of the PI controller; the internal structure of the PI controller in the MATLAB platform is as follows: the signal obtained by integrating the input signal and the signal obtained by passing the input signal through the proportional link are added, and the added signal is limited in amplitude to obtain the output signal of the PI controller. It can be seen that the output limiting principles of the two are different. The output limiting of the PI controller in ADPSS is added to the integration link, and the module output is obtained by superimposing the proportional link and the limited-amplitude integration link, while the output limiting of the PI controller in SIMULINK is added at the output port, resulting in obvious peak differences in the transient stage of the module output.

[0093] The principles of the hysteresis comparators used for fault flag bit judgment in the measurement circuit are different, as Figure 4 shown. The input parameters of the hysteresis comparator in the ADPSS platform include the interval average value M and the interval margin HY. The input parameters of the hysteresis comparator in the MATLAB platform include the opening point ON and the closing point OFF. Mismatch in the parameter settings of the hysteresis comparator in the ADPSS platform will result in different fault flag bit signals output by using this module, thereby causing different control strategy switching times for the two simulation models and resulting in differences in the transient characteristics between the simulation models.

[0094] The differences between different sub-modules of the battery energy storage system simulation models on the ADPSS and MATLAB platforms act on the overall model comprehensively, resulting in differences in the steady-state characteristics and transient response characteristics of the battery energy storage system models on the two platforms. Based on the analysis of the response characteristic differences and module differences, the present invention constructs the mapping relationship between the module differences and characteristic differences between the ADPSS platform and the MATLAB platform, as shown in Table 1.

[0095] Table 1 Mapping relationship between module differences and characteristic differences between platforms

[0096]

[0097] S4. For the ADPSS platform, a verification method for the differential modules between platforms is proposed.

[0098] Based on the basic sub-module difference analysis in S3, from the three dimensions of the main circuit, control circuit, and measurement circuit, two module verification methods, namely module parameter verification based on formulas and module structure verification based on module response differences, are adopted. Using the MATLAB platform module as a reference, the ADPSS simulation model is verified.

[0099] 1) Main circuit check: According to the differences in the equivalent circuits of the three-phase two-winding transformers of the two platforms used for encapsulation parameter calculation mentioned in S3, and the magnitudes of the branch resistance R z and the branch resistance X z in the MATLAB platform, set the parameters of the transformer module in the ADPSS model. The calculation formulas for the resistance R m and the reactance X m of the excitation branch of the transformer are as follows:

[0100]

[0101] 2) Control circuit check: Conduct a structural check on the PI controllers with differences. The check method is as follows: Set the limit parameters of the PI controller in ADPSS to infinity to eliminate the influence of the limit parameters of the integral link of the PI controller on this platform, and add a separate limit element at the output port of the PI controller. The parameter settings of this limit element are the same as those of the PI controller limit parameters in the MATLAB platform. Through the above check method, the output effects of the PI controllers on the two platforms can be made consistent. The structural diagram of the PI controller model after checking is as Figure 5 shown.

[0102] 3) Measurement circuit check: Conduct a parameter check on the hysteresis comparators with differences. The corresponding principle between the output settings of the SIMULINK hysteresis comparator and the output channels of the ADPSS hysteresis comparator is shown in Table 2. According to the turn-on point ON and turn-off point OFF of the hysteresis comparator parameters in the MATLAB platform, set the interval average value M and interval margin HY of the hysteresis comparator on the ADPSS platform. The parameter setting formulas are as follows:

[0103]

[0104]

[0105] Table 2 Corresponding principle of hysteresis comparator output

[0106]

[0107] By comparing the deviation between the response data of the ADPSS platform simulation model before and after checking and the manufacturer's test response data under standard test conditions, it is verified that the simulation accuracy of the model after being checked by the present invention has been greatly improved:

[0108] The proposed method for checking the differences between platforms is used to check the basic simulation model built on the ADPSS simulation platform. According to the "Regulations for Testing Model Parameters of Electrochemical Energy Storage Power Stations - Draft for Comment", the ADPSS simulation model before and after checking is subjected to a fault ride-through simulation test to obtain the response data of the simulation model. Through the comparison of the response curves, it is preliminarily verified that the response characteristics of the model after checking are more consistent.

[0109] According to the standard allowable maximum deviation and the deviation calculation method in the "Regulations for Testing Model Parameters of Electrochemical Energy Storage Power Stations - Draft for Comment", the deviations between the simulation data of the ADPSS model before and after checking and the manufacturer's test data are quantitatively analyzed. It is verified that the deviation after checking is significantly lower than that before checking and is far lower than the standard allowable maximum deviation. The deviation calculation method is as follows:

[0110] Steady-state interval average deviation F 1 And transient interval average deviation F 2 The calculation formulas are as follows:

[0111]

[0112] Maximum deviation F in the steady-state interval 3 The calculation formula is as follows:

[0113]

[0114] The calculation formula for the weighted average deviation is as follows:

[0115] F G =0.1F 1_A +0.6F 1_B +0.3F 1_C (3)

[0116] Where: X M And X S Respectively represent the per-unit values of the manufacturer's model test data and the simulation data of the simulation model for the electrical quantity to be evaluated; K Start And K End Respectively represent the sequence numbers of the first and last data in the error calculation interval; F 1_A 、F 1_B 、F 1_C Are the steady-state interval average deviations in the three stages before, during, and after the fault respectively, and the partition is based on the "Regulations for Testing Model Parameters of Electrochemical Energy Storage Power Stations - Draft for Comment".

[0117] More specifically, the low- and high-voltage fault standard test conditions are based on the "Regulations for Testing Model Parameters of Electrochemical Energy Storage Power Stations - Draft for Comment", and the response data includes the positive-sequence voltage, current, reactive current, active power, and reactive power at the grid connection point.

[0118] Voltage fault standard test conditions: including the energy storage system operating in a steady state at high power (0.9 p.u. - 1.0 p.u.) or low power (0.1 p.u. - 0.3 p.u.), and the operating mode being charging or discharging. When the three-phase grid voltage drops to 90%, 80%, 75%, 70%, 60%, 50%, 40%, 35%, 30%, 20%, 10% and 0%, or rises to 110%, 115%, 120%, 125%, 130%, 135% and 140%, each combination of these situations is regarded as a test condition, with a total of at least 12 * 2 * 2 + 7 * 2 * 2 = 76 kinds.

[0119] Embodiment

[0120] Perform simulation according to the method described in the specific implementation manner.

[0121] Taking a 200 kW battery energy storage unit of a certain manufacturer as an example, this invention established a simulation model of this type of energy storage system based on the ADPSS simulation platform, and used the verification method proposed by this invention to verify the simulation model. By comparing the deviation between the fault ride-through responses of the ADPSS platform simulation model before and after verification and the test responses of the manufacturer, the effect of the verification method proposed by this invention on improving the simulation accuracy of the ADPSS model was verified.

[0122] 1. Verify the consistency of the trend of the response characteristic curve.

[0123] Select the initial discharge power of 1.0 p.u., and show the comparison of the response characteristics between the ADPSS simulation model before and after verification and the manufacturer's test for four low / high voltage fault conditions where the grid voltage faults to 0.2 p.u. and 0.5 p.u. with durations of 0.625 s respectively, the grid voltage drops to last for 1.21 s, the grid voltage rises to 1.25 p.u. and lasts for 1 s, and the grid voltage rises to 1.3 p.u. and lasts for 0.5 s, as Figures 6 - 9 shown. Under the same charge and discharge mode, voltage fault amplitude and fault time, compare the transient response characteristic curves of the simulation model before and after verification with the manufacturer's encapsulated model. The response characteristic curve of the model after verification has a higher consistency with the test results of the manufacturer's encapsulated model, and the model after verification has been significantly corrected in both steady-state characteristics and transient characteristics.

[0124] 2. Verify the effectiveness of the verification method through deviation calculation and comparison based on quantitative analysis.

[0125] Select the initial discharge power of 1.0 p.u., and show the quantization results of the model deviation for two conditions where the voltage symmetrically drops to 0.5 p.u. and the voltage symmetrically rises to 1.25 p.u. The calculation results of the response deviation before and after model verification are compared as Figures 10 - 11As shown in the figure, the purple surface in the figure represents the standard allowable deviation, and the yellow and cyan square columns respectively represent the response deviations of the ADPSS simulation model before and after verification compared with the manufacturer's packaged model. Under the selected operating conditions, the response deviation of the ADPSS simulation model before verification compared with the manufacturer's packaged model can reach up to 12.53%, while the response deviations at each stage of the model after verification are all reduced to less than 1.63%. The response deviation of the ADPSS simulation model after verification is significantly lower than that before verification and is significantly lower than the maximum allowable standard deviation, verifying the effectiveness of the model verification method proposed in the present invention.

[0126] In summary, the present invention proposes a method for verifying the electromagnetic transient simulation model of the battery energy storage system on the ADPSS platform. Aiming at the new generation of domestic ADPSS simulation platform, the mapping relationship between the module differences and characteristic differences between platforms is proposed based on the widely used mainstream simulation platform MATLAB. Based on the analysis of the digital model differences of the modules and their mapping relationship with the characteristic differences, a verification method for the different modules between platforms is proposed to realize the verification of the overall simulation model and improve the simulation accuracy of the ADPSS simulation model. The present invention can effectively improve the simulation accuracy of the ADPSS model, contribute to the domestic substitution of the battery energy storage system simulation technology, and facilitate the application and popularization of domestic software in the research of energy storage system simulation technology. Specific Embodiment 2:

[0128] This embodiment is a system for verifying the electromagnetic transient simulation model of the battery energy storage system on the ADPSS platform. The system verifies the simulation model of the battery energy storage system constructed based on the ADPSS platform and the MATLAB platform;

[0129] The simulation model of the battery energy storage system includes a main circuit, a control circuit, and a measurement circuit;

[0130] The main circuit corresponding to the simulation model of the battery energy storage system includes an energy storage battery model, a capacitor, a converter, a filter, and a step-up transformer. Among them, the converter is the bridge for the energy storage system to be connected to the grid. The DC side of the converter includes a battery model and a capacitor, and the DC capacitor is connected in parallel with the battery model. The AC side of the converter includes a filter and a step-up transformer. The step-up transformer adopts a three-phase two-winding transformer. The low-voltage side of the transformer is the energy storage side, and the high-voltage side of the transformer is the grid side. The output power of the energy storage side is fed into the collector network through the step-up transformer;

[0131] The control circuit includes a steady-state control circuit, a low-voltage ride-through control circuit, and a high-voltage ride-through control circuit. The control circuit generates the abc three-phase voltages on the AC side of the converter and transmits them to the converter. The steady-state control circuit adopts double-loop decoupling control, which includes a power outer loop and a current inner loop. The double-loop decoupling control realizes independent control of active and reactive power. The active power control and reactive power control of the low-voltage ride-through control circuit both adopt a single-current inner loop control structure. The active power control of the high-voltage ride-through control circuit continues to use the steady-state double-loop control circuit for active power, and the reactive power control adopts a single-current inner loop control structure.

[0132] The measurement circuit is responsible for obtaining the voltage and output current from the grid connection point of the energy storage system, performing coordinate transformation and power calculation on the obtained voltage and current to obtain the electrical quantities required for control. It compares the positive-sequence voltage u at the grid connection point in the electrical quantities required for control with the voltage thresholds for entering and exiting low / high ride-through of active and reactive power to judge the voltage ride-through flag bit. The flag bit is used to control the switching of the steady-state and low / high ride-through control states of the control circuit. The comparison between the positive-sequence voltage u at the grid connection point and the voltage threshold uses the hysteresis comparator module in the ADPSS platform and the basic module library of the MATLAB platform.

[0133] The system includes a main circuit verification unit, a control circuit verification unit, and a measurement circuit verification unit. Among them,

[0134] Main circuit verification unit: For the three-phase two-winding transformer on the two platforms, based on the magnitudes of the branch resistance R z and branch resistance X z set on the MATLAB platform, the parameters of the transformer module in the ADPSS model are set: the exciting branch resistance of the transformer the exciting branch reactance of the transformer

[0135] Control circuit verification unit: Conducts a structural verification on the PI controllers with differences. Sets the limit parameters of the PI controller in ADPSS to infinity, and adds a separate limit element at the output port of the PI controller. The parameter settings of the limit element are the same as the limit parameter settings of the PI controller on the MATLAB platform.

[0136] Measurement circuit verification unit: Conducts parameter verification on the hysteresis comparators with differences. Sets the interval average value M and interval margin HY of the hysteresis comparator on the ADPSS platform according to the ON point and OFF point of the hysteresis comparator parameters on the MATLAB platform.

[0137] It should be understood that the system described in this embodiment is a computer program product, software, or computerized method that runs in the form of instructions. Specific Embodiment Three:

[0139] This embodiment is a computer storage medium, in which at least one instruction is stored, and the at least one instruction is loaded and run by a processor to execute an ADPSS platform battery energy storage system electromagnetic transient simulation model verification system.

[0140] It should be understood that the instruction includes a computer program product, software, or computerized method corresponding to any method described in the present invention; the instruction can be used to program a computer system or other electronic devices. The computer storage medium can include a readable medium on which the instruction is stored, which can include but is not limited to a magnetic storage medium and an optical storage medium; the magneto-optical storage medium includes a read-only memory ROM, a random access memory RAM, an erasable programmable memory (e.g., EPROM and EEPROM), and a flash memory layer, or other types of media suitable for storing electronic instructions. Specific Embodiment 4:

[0142] This embodiment is an ADPSS platform battery energy storage system electromagnetic transient simulation model verification device, which includes a processor and a memory. It should be understood that it includes any device including a processor and a memory described in the present invention, and the device can also include other units and modules that perform display, interaction, processing, control, etc. and other functions through signals or instructions;

[0143] At least one instruction is stored in the memory, and the at least one instruction is loaded and run by the processor to execute an ADPSS platform battery energy storage system electromagnetic transient simulation model verification system.

[0144] The above calculation examples of the present invention are only for explaining in detail the calculation model and calculation process of the present invention, rather than limiting the embodiments of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made on the basis of the above description. It is impossible to enumerate all the embodiments here. Any obvious changes or modifications derived from the technical solutions of the present invention still fall within the protection scope of the present invention.

Claims

1. A method for verifying electromagnetic transient simulation model of battery energy storage system on ADPSS platform, characterized in that: The simulation model of the battery energy storage system is constructed based on the ADPSS platform and the MATLAB platform respectively. The simulation model of the battery energy storage system includes the main circuit, the control circuit and the measurement circuit. The main circuit corresponding to the battery energy storage system simulation model includes an energy storage battery model, capacitors, converters, filters, and step-up transformers. The converter is the bridge for the energy storage system to be connected to the grid. The DC side of the converter includes a battery model and capacitors, and the DC capacitors are connected in parallel with the battery model. The AC side of the converter includes filters and step-up transformers. The step-up transformer uses a three-phase two-winding transformer. The low-voltage side of the transformer is the energy storage side, and the high-voltage side of the transformer is the grid side. The output power of the energy storage side is fed into the collection network through the step-up transformer. The control circuit includes a steady-state control circuit, a low voltage ride-through control circuit and a high voltage ride-through control circuit. The control circuit generates the three-phase voltage abc on the AC side of the converter and transmits it to the converter. The steady-state control circuit adopts a double closed-loop decoupling control, which includes a power outer loop and a current inner loop. The double closed-loop decoupling control realizes independent control of active power and reactive power. The active power control and reactive power control of the low voltage ride-through control circuit both adopt a single current inner loop control structure. The active power control of the high voltage ride-through control circuit continues to use the active steady-state double closed-loop control circuit, and the reactive power control adopts a single current inner loop control structure. The measurement circuit is responsible for obtaining the voltage and output current from the grid-connected point of the energy storage system, performing coordinate system transformation and power calculation on the obtained voltage and current to obtain the electrical quantity required for control; comparing the grid-connected point positive sequence voltage u in the electrical quantity required for control with the voltage thresholds for active and reactive power to enter and exit low / high wear to determine the voltage ride-through flag, which is used to control the steady state of the circuit and the switching of the low / high wear control state; the comparison between the positive sequence voltage u and the voltage threshold uses the hysteresis comparator module in the basic module library of the ADPSS platform and the MATLAB platform; For the main circuit, control circuit and measurement circuit, the ADPSS simulation model is calibrated using the MATLAB platform module as a benchmark; Main circuit verification: For the three-phase two-winding transformer on the two platforms, the branch resistance R is set based on the MATLAB platform z And branch resistance X z The size of the transformer module of the ADPSS model is set by parameters: transformer excitation branch resistance Transformer excitation branch reactance Control circuit verification: perform structural verification on the PI controller with differences, set the limit parameter of the ADPSS PI controller to infinity, and add a separate limit element to the output port of the PI controller. The parameter setting of the limit element is consistent with the limit parameter size setting of the PI controller on the MATLAB platform. Measurement circuit calibration: Parameter calibration is performed on the hysteresis comparator with differences. According to the MATLAB platform hysteresis comparator parameter opening point ON and closing point OFF, the interval average value M and interval margin HY of the hysteresis comparator of the ADPSS platform are set:

2. According to claim 1, a method for verifying an electromagnetic transient simulation model of an ADPSS platform battery energy storage system is characterized in that: The battery model on the DC side of the main circuit corresponding to the battery energy storage system simulation model is based on the Rint model, and the constant voltage source in the Rint model is changed to a controlled voltage source.

3. According to claim 2, a method for verifying an electromagnetic transient simulation model of an ADPSS platform battery energy storage system is characterized in that: In the charging and discharging modes, the magnitudes of the voltage E of the controlled voltage source of the battery model are f1 and f2 respectively: Where: i is the battery current; i s 、i * They are the integral current of the battery current and the filtered current of the battery current respectively; A is the voltage drop in the exponential region; B is the time constant in the exponential region; K is the polarization voltage; E0 is the nominal voltage, and Q is the battery capacity.

4. The method for verifying the electromagnetic transient simulation model of the ADPSS platform battery energy storage system according to claim 1, characterized in that: The filter on the AC side of the converter uses an LC filter.

5. The method for verifying the electromagnetic transient simulation model of the ADPSS platform battery energy storage system according to claim 1, characterized in that: The electrical quantities required for the control include: the d-axis component e of the transformer low-voltage side voltage d , q-axis component of transformer low-voltage side voltage e q , active current i d , reactive current i q , grid-connected point positive sequence voltage u, active power P, reactive power Q.

6. A method for verifying an electromagnetic transient simulation model of an ADPSS platform battery energy storage system according to any one of claims 1 to 5, characterized in that: In the process of coordinate system transformation and power calculation of the acquired voltage and current, the dq to abc module in the basic module library of the ADPSS platform and MATLAB platform is used for coordinate system transformation.

7. A method for verifying an electromagnetic transient simulation model of an ADPSS platform battery energy storage system according to any one of claims 1 to 5, characterized in that: In the process of coordinate system transformation and power calculation of the acquired voltage and current, the power calculation adopts the instantaneous power calculation module in the basic module library of the ADPSS platform and the MATLAB platform.

8. An electromagnetic transient simulation model verification system for an ADPSS platform battery energy storage system, characterized in that: The system verifies the simulation model of the battery energy storage system built on the ADPSS platform and the MATLAB platform; The battery energy storage system simulation model built on the ADPSS platform and MATLAB platform includes the main circuit, control circuit and measurement circuit; The main circuit includes an energy storage battery model, capacitors, converters, filters, and step-up transformers. The converter is the bridge for the energy storage system to be connected to the grid. The DC side of the converter includes a battery model and capacitors, and the DC capacitors are connected in parallel with the battery model. The AC side of the converter includes filters and step-up transformers. The step-up transformer uses a three-phase two-winding transformer. The low-voltage side of the transformer is the energy storage side, and the high-voltage side of the transformer is the grid side. The output power of the energy storage side is fed into the collection network through the step-up transformer. The control circuit includes a steady-state control circuit, a low voltage ride-through control circuit and a high voltage ride-through control circuit. The control circuit generates the three-phase voltage abc on the AC side of the converter and transmits it to the converter. The steady-state control circuit adopts a double closed-loop decoupling control, which includes a power outer loop and a current inner loop. The double closed-loop decoupling control realizes independent control of active power and reactive power. The active power control and reactive power control of the low voltage ride-through control circuit both adopt a single current inner loop control structure. The active power control of the high voltage ride-through control circuit continues to use the active steady-state double closed-loop control circuit, and the reactive power control adopts a single current inner loop control structure. The measurement circuit is responsible for obtaining the voltage and output current from the grid-connected point of the energy storage system, performing coordinate system transformation and power calculation on the obtained voltage and current to obtain the electrical quantity required for control; comparing the grid-connected point positive sequence voltage u in the electrical quantity required for control with the voltage thresholds for active and reactive power to enter and exit low / high wear to determine the voltage ride-through flag, which is used to control the steady state and low / high wear control state switching of the circuit; the comparison between the grid-connected point positive sequence voltage u and the voltage threshold adopts the hysteresis comparator module in the basic module library of the ADPSS platform and the MATLAB platform; The system includes a main circuit calibration unit, a control circuit calibration unit and a measurement circuit calibration unit; wherein, Main circuit verification unit: for the three-phase two-winding transformer on the two platforms, the branch resistance R is set based on the MATLAB platform z And branch resistance X z The size of the transformer module of the ADPSS model is set by parameters: transformer excitation branch resistance Transformer excitation branch reactance Control circuit verification unit: perform structural verification on the PI controller with differences, set the limit parameter of the ADPSS PI controller to infinity, and add a separate limit element to the output port of the PI controller. The parameter setting of the limit element is consistent with the limit parameter size setting of the PI controller on the MATLAB platform. Measurement circuit calibration unit: Parameter calibration of the hysteresis comparator with differences is performed. According to the ON and OFF points of the hysteresis comparator parameters on the MATLAB platform, the interval average value M and interval margin HY of the hysteresis comparator on the ADPSS platform are set:

9. A computer storage medium, characterized in that: The storage medium stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement the electromagnetic transient simulation model verification system for the ADPSS platform battery energy storage system as described in claim 8.

10. An electromagnetic transient simulation model calibration device for an ADPSS platform battery energy storage system, characterized in that: The device includes a processor and a memory, wherein the memory stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement an electromagnetic transient simulation model verification system for an ADPSS platform battery energy storage system as described in claim 8.

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