Fault ride-through control method and system for electromechanical transient model of electrochemical energy storage

Abstract

The present invention discloses a fault ride-through control method and system for an electrochemical energy storage electromechanical transient model, which belongs to the field of power systems and automation technology. The method of the present invention includes: in different charge and discharge states and different fault ride-through control strategy scenarios, in the fault ride-through recovery process stage, setting the fault ride-through recovery process characteristics; after setting the fault ride-through recovery process characteristics, in the fault ride-through end stage, based on recording the current active power command value, the current reactive power command value and the set power demand of the electrochemical energy storage system, determining the end time of the fault ride-through end stage; based on the end time, determining the power command after the end of the fault ride-through, and controlling the electrochemical energy storage system after the fault with the power command. The present invention can support the simulation calculation requirements of the electrochemical energy storage system in different charge and discharge states and different fault ride-through control strategy scenarios.

Description

Technical Field

[0001] The present invention relates to the field of power systems and automation technologies, and more particularly to a fault ride-through control method and system for an electrochemical energy storage electromechanical transient model. Background Art

[0002] As a flexible resource for regulating power systems, energy storage systems play a significant role in supporting renewable energy consumption, power system operation, and safe and stable control. Electrochemical energy storage offers comprehensive advantages in power density, response time, and operating life, making it a crucial component of emerging power systems and increasingly involved in system planning and operation. For large power grids, electrochemical energy storage offers significant advantages in technological maturity and economic feasibility, and has already reached engineering application, such as peak shaving, power flow control, smoothing renewable energy fluctuations, system voltage regulation, system frequency regulation, and power control.

[0003] Research on the integration of energy storage power stations into large power grids requires the construction of electromechanical transient simulation models for electrochemical energy storage systems. Currently, models suitable for large power grid simulation have been proposed both domestically and internationally and implemented in large power grid simulation software. For example, an electromechanical transient simulation model for energy storage power stations has been constructed based on the generator control model REGC_A, the electrical control model REEC_C, and the plant-level control model REPC_A, a general control model for renewable energy models proposed by the Western Electricity Coordinating Council (WECC) in the United States. Similarly, my country's PSD and PSASP simulation software have also initially constructed electromechanical transient simulation models for energy storage power stations and used them for simulation and analysis of actual large power grids. However, these models primarily rely on the control strategies of wind power and photovoltaic power generation, and are less comprehensive in terms of power control during fault voltage ride-through, with the following deficiencies.

[0004] Fault ride-through characteristics are key to the stable grid connection and grid support capabilities of energy storage systems. Similar to photovoltaic and wind power generation systems, large-scale electrochemical energy storage systems must be able to withstand abnormal voltages and frequencies. When the tolerance range is exceeded, the protection system will activate and disconnect the energy storage system. Currently, national and industry standards have standardized the low-voltage ride-through or high-voltage ride-through technical requirements for energy storage systems, clarifying the thresholds for energy storage power stations to enter and exit high and low voltage ride-through. However, during the fault ride-through period, (1) the power support control strategy of the energy storage system lacks unified standards, resulting in different power control strategies for the electrochemical energy storage power stations actually put into operation during the voltage ride-through period; (2) when designing the fault ride-through control strategy, the manufacturer's equipment mainly refers to the fault ride-through control strategy of conventional wind power and photovoltaic power (output power) for the discharge state (output power) of the energy storage power station, but it is difficult to directly apply it to the fault ride-through control strategy of the energy storage system in the charging state (absorption power); (3) in the power recovery stage, the manufacturer's parameters generally give the absolute value of the recovery rate, but depending on the different fault ride-through control strategies, the recovery process may have a positive slope or a negative slope. In combination with the different charging and discharging states, the logic is complex and there is a lack of a universal visual method. Summary of the Invention

[0005] To address the above problems, the present invention proposes a fault ride-through control method for an electromechanical transient model of electrochemical energy storage, comprising:

[0006] Under different charge and discharge states and different fault ride-through control strategy scenarios, at the start of the fault ride-through phase, the current active power command value and the current reactive power command value of the electrochemical energy storage system are recorded. During the fault ride-through phase, the power demand is set. During the fault ride-through recovery phase, the fault ride-through recovery process characteristics are set.

[0007] After the fault ride-through recovery process characteristics are set, at the end of the fault ride-through phase, the end time of the fault ride-through phase is determined based on the current active power command value, the current reactive power command value, and the set power demand of the electrochemical energy storage system.

[0008] Based on the end time, a power instruction after the fault ride-through is completed is determined, and the electrochemical energy storage system after the fault is controlled by the power instruction.

[0009] Optionally, the current active power command value and the current reactive power command value of the electrochemical energy storage system are recorded as P0 and Q0 respectively;

[0010] Among them, P0 is less than 0 in the charging state and P0 is greater than 0 in the discharging state; the reactive power emitted is Q0 greater than 0 and the reactive power absorbed is Q0 less than 0.

[0011] Optionally, during the fault ride-through phase, power requirements can be set, including:

[0012] An active power instruction P1 is set during the fault ride-through period. When the electrochemical energy storage system lacks active power support during the fault ride-through period, if the electrochemical energy storage system is adjusted to a discharge condition and outputs active power, P1>0; if the electrochemical energy storage system is adjusted to a charge condition and absorbs active power, P1<0;

[0013] The reactive power instruction Q1 is set during the fault ride-through period. When the electrochemical energy storage system lacks reactive power support during the fault ride-through period, if the electrochemical energy storage system is adjusted to output reactive power, Q1>0 at this time; if the electrochemical energy storage system is adjusted to absorb reactive power, Q1<0 at this time.

[0014] Optionally, during the fault ride-through recovery phase, configure the fault ride-through recovery process characteristics, including:

[0015] When the active power recovery mode is set to immediate recovery, the active power instruction of the fault travel recovery process is set to the initial power; when the active power recovery mode is set to recovery according to the slope, the active power instruction value of the fault travel recovery process is calculated in real time;

[0016] Specify reactive power command value according to support requirements.

[0017] Optionally, when the active power recovery mode is set to immediate recovery, the start time of the fault ride-through recovery process phase is the same as the end time of the fault ride-through end phase.

[0018] Optionally, based on the end time, a calculation formula for determining the power instruction after the fault ride-through ends is as follows:

[0019] P3(t)=P0,t>t2

[0020] Q3(t)=Q0,t>t2

[0021] Among them, P3(t) and Q3(t) are the reset active power command value and reactive power command value respectively, P0,t and Q0,t are the initial active power command value and reactive power command value respectively, and t2 is the end time.

[0022] In another aspect, the present invention further proposes a fault ride-through control system for an electromechanical transient model of electrochemical energy storage, comprising:

[0023] An initialization unit is used to record the current active power command value and the current reactive power command value of the electrochemical energy storage system at the start time of the fault ride-through phase under different charge and discharge states and different fault ride-through control strategy scenarios, set the power demand during the fault ride-through phase, and set the fault ride-through recovery process characteristics during the fault ride-through recovery phase;

[0024] A setting unit is configured to determine, after the fault ride-through recovery process characteristics are set, an end time of the fault ride-through end phase based on the recorded current active power command value, current reactive power command value, and set power demand of the electrochemical energy storage system at the end phase of the fault ride-through;

[0025] The control unit is used to determine a power instruction after the fault ride-through is completed based on the end time, and control the electrochemical energy storage system after the fault with the power instruction.

[0026] Optionally, the current active power command value and the current reactive power command value of the electrochemical energy storage system recorded by the initial unit are recorded as P0 and Q0 respectively;

[0027] Among them, P0 is less than 0 in the charging state and P0 is greater than 0 in the discharging state; the reactive power emitted is Q0 greater than 0 and the reactive power absorbed is Q0 less than 0.

[0028] Optionally, during the fault ride-through phase, power requirements can be set, including:

[0029] An active power instruction P1 is set during the fault ride-through period. When the electrochemical energy storage system lacks active power support during the fault ride-through period, if the electrochemical energy storage system is adjusted to a discharge condition and outputs active power, P1>0; if the electrochemical energy storage system is adjusted to a charge condition and absorbs active power, P1<0;

[0030] The reactive power instruction Q1 is set during the fault ride-through period. When the electrochemical energy storage system lacks reactive power support during the fault ride-through period, if the electrochemical energy storage system is adjusted to output reactive power, Q1>0 at this time; if the electrochemical energy storage system is adjusted to absorb reactive power, Q1<0 at this time.

[0031] Optionally, during the fault ride-through recovery phase, configure the fault ride-through recovery process characteristics, including:

[0032] When the active power recovery mode is set to immediate recovery, the active power instruction of the fault travel recovery process is set to the initial power; when the active power recovery mode is set to recovery according to the slope, the active power instruction value of the fault travel recovery process is calculated in real time;

[0033] Specify reactive power command value according to support requirements.

[0034] Optionally, when the active power recovery mode is set to immediate recovery, the start time of the fault ride-through recovery process phase is the same as the end time of the fault ride-through end phase.

[0035] Optionally, based on the end time, a calculation formula for determining the power instruction after the fault ride-through ends is as follows:

[0036] P3(t)=P0,t>t2

[0037] Q3(t)=Q0,t>t2

[0038] Among them, P3(t) and Q3(t) are the reset active power command value and reactive power command value respectively, P0,t and Q0,t are the initial active power command value and reactive power command value respectively, and t2 is the end time.

[0039] In yet another aspect, the present invention further provides a computing device comprising: one or more processors;

[0040] a processor for executing one or more programs;

[0041] When the one or more programs are executed by the one or more processors, the above-described method is implemented.

[0042] In another aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed, the method described above is implemented.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] The present invention provides a fault ride-through control method for an electrochemical energy storage electromechanical transient model, comprising: recording the current active power command value and the current reactive power command value of the electrochemical energy storage system at the start of the fault ride-through phase under different charge and discharge states and different fault ride-through control strategy scenarios, setting the power demand during the fault ride-through phase, and setting the fault ride-through recovery process characteristics during the fault ride-through recovery phase; after setting the fault ride-through recovery process characteristics, determining the end time of the fault ride-through end phase based on the recorded current active power command value, the current reactive power command value, and the set power demand at the end of the fault ride-through phase; determining the power command after the end of the fault ride-through based on the end time, and controlling the electrochemical energy storage system after the fault with the power command. The present invention can support the simulation and calculation needs of electrochemical energy storage systems under different charge and discharge states and different fault ride-through control strategy scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a flow chart of the method of the present invention;

[0046] Figure 2 A diagram showing the division of different stages of an energy storage power station fault ride-through according to an embodiment of the method of the present invention;

[0047] Figure 3 3a and 3b are diagrams showing the active power change process and reactive power change process of immediate recovery in the simulation results of a typical fault ride-through process of an embodiment of the method of the present invention;

[0048] Figure 4 4a and 4b are typical fault ride-through simulation results of the method embodiment of the present invention, showing enhanced active power support during the fault in the discharge state and surplus power absorption during the fault;

[0049] Figure 5 5a and 5b are typical fault ride-through simulation results of the method embodiment of the present invention, showing enhanced active power support during a fault in a charging state and surplus power absorption during a fault;

[0050] Figure 6 It is a structural diagram of the system of the present invention. DETAILED DESCRIPTION

[0051] Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to provide a thorough and complete disclosure of the present invention and to fully convey the scope of the present invention to those skilled in the art. The terminology used in the exemplary embodiments shown in the accompanying drawings is not intended to limit the present invention. In the accompanying drawings, identical elements are denoted by the same reference numerals.

[0052] Unless otherwise specified, the terms used herein (including technical terms) have the meanings commonly understood by those skilled in the art. In addition, it is understood that terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0053] Example 1:

[0054] The present invention proposes a fault ride-through control method for electrochemical energy storage electromechanical transient model, such as Figure 1 As shown, including:

[0055] Step 1: Under different charge and discharge states and different fault ride-through control strategy scenarios, at the start of the fault ride-through phase, record the current active power command value and the current reactive power command value of the electrochemical energy storage system; during the fault ride-through phase, set the power demand; and during the fault ride-through recovery phase, set the fault ride-through recovery process characteristics;

[0056] Step 2: After setting the fault ride-through recovery process characteristics, at the end of the fault ride-through phase, the end time of the fault ride-through phase is determined based on the current active power command value, the current reactive power command value, and the set power demand of the electrochemical energy storage system.

[0057] Step 3: Based on the end time, determine a power instruction after the fault ride-through is completed, and control the electrochemical energy storage system after the fault with the power instruction.

[0058] Among them, the current active power command value and the current reactive power command value of the electrochemical energy storage system are recorded and recorded as P0 and Q0 respectively;

[0059] Among them, P0 is less than 0 in the charging state and P0 is greater than 0 in the discharging state; the reactive power emitted is Q0 greater than 0 and the reactive power absorbed is Q0 less than 0.

[0060] During the fault ride-through phase, the power demand is set, including:

[0061] An active power instruction P1 is set during the fault ride-through period. When the electrochemical energy storage system lacks active power support during the fault ride-through period, if the electrochemical energy storage system is adjusted to a discharge condition and outputs active power, P1>0; if the electrochemical energy storage system is adjusted to a charge condition and absorbs active power, P1<0;

[0062] The reactive power instruction Q1 is set during the fault ride-through period. When the electrochemical energy storage system lacks reactive power support during the fault ride-through period, if the electrochemical energy storage system is adjusted to output reactive power, Q1>0 at this time; if the electrochemical energy storage system is adjusted to absorb reactive power, Q1<0 at this time.

[0063] During the fault ride-through recovery process, the fault ride-through recovery process characteristics are set, including:

[0064] When the active power recovery mode is set to immediate recovery, the active power instruction of the fault travel recovery process is set to the initial power; when the active power recovery mode is set to recovery according to the slope, the active power instruction value of the fault travel recovery process is calculated in real time;

[0065] Specify reactive power command value according to support requirements.

[0066] When the active power recovery mode is set to immediate recovery, the start time of the fault ride-through recovery process phase is the same as the end time of the fault ride-through end phase.

[0067] The calculation formula for determining the power command after the fault ride-through is completed based on the end time is as follows:

[0068] P3(t)=P0,t>t2

[0069] Q3(t)=Q0,t>t2

[0070] Among them, P3(t) and Q3(t) are the reset active power command value and reactive power command value respectively, P0,t and Q0,t are the initial active power command value and reactive power command value respectively, and t2 is the end time.

[0071] The present invention is further described below with reference to specific cases:

[0072] Step 1: First, divide the fault ride-through process into four stages, such as Figure 2 As shown, specifically, it includes the start time of fault ride-through, the fault ride-through period, the fault ride-through recovery process, and the end time of fault ride-through. The start time of fault ride-through is t0, the end time of the fault ride-through period and the start time of fault ride-through recovery are t1, and the end time of fault ride-through is t2. Then, the power command value of the energy storage system is calculated for different stages.

[0073] Step 2: At the start of fault ride-through, instant t0, record the energy storage system's current active power and reactive power command values, denoted as P0 and Q0, respectively. Active power and reactive power can be positive or negative depending on the application scenario. For active power, P0 < 0 in the charging state and P0 > 0 in the discharging state; for emitted reactive power, Q0 > 0, and absorbed reactive power, Q0 < 0.

[0074] Step 3: Specify the active power P1 and reactive power command value Q1 during the fault ride-through period (corresponding to time t0 to time t1). These two serve as input parameters of the strategy and can be arbitrarily set according to the power demand of the actual grid scenario (without considering the initial charge and discharge state), thereby achieving a flexible power support function. However, the maximum power and maximum current limits must be met.

[0075] Step 3-1 sets the active power command P1. When the system lacks active power support during a fault, the energy storage system can be adjusted to a discharging condition, outputting active power (P1>0), supporting the system frequency and preventing further frequency drops. Conversely, the energy storage system can be adjusted to a charging condition, absorbing active power (P1<0), reducing the system's surplus power and helping to stabilize the synchronous machine's power angle.

[0076] Step 3-2: Set the reactive power instruction Q1. When the system lacks reactive power support during a fault, the energy storage system can be adjusted to output reactive power, Q1>0, to support the system voltage. Conversely, the energy storage system can be adjusted to absorb reactive power, Q1<0, to suppress system overvoltage.

[0077] Step 4: Set the fault ride-through recovery process (corresponding to time t1 to time t2). The manufacturer's strategy is generally to set the active power recovery coefficient K. p Achieve, and K p This is a consistently positive value, representing the rate of power recovery. This process is complex for both simulation models and program implementations, requiring consideration of different charging and discharging states, as well as different initial operating conditions, and real-time calculation of the active and reactive power command values, P2(t) and Q2(t), where t is the current simulation time. The detailed implementation is as follows.

[0078] Step 4.1: Determine the active power recovery method. During a fault, the energy storage system's generator-side voltage deviates from the rated operating voltage and is limited by the converter's maximum overcurrent capability. Consequently, the energy storage system's active power command deviates significantly from the initial power. However, during fault recovery, the generator-side voltage essentially returns to the rated voltage level, allowing the energy storage system to restore its initial operating power. Depending on the strategies of different manufacturers, it's necessary to clearly define the active power recovery method, which can be categorized as immediate recovery or slope-based recovery.

[0079] When set to restore immediately, the current active power command is set to the initial power, that is:

[0080] P2(t)=P0,t=t1

[0081] Q2(t)=Q0,t=t1

[0082] If the system is set to restore by slope, proceed to step 4.2.

[0083] Step 4.2: Calculate the active power reference value P2(t) in real time during the recovery process. At this time, the power operating level of the fault condition needs to be processed according to the situation, and the calculation is performed as follows:

[0084]

[0085] Step 4.3: Calculate the reactive power reference value Q2(t) in real time during the recovery process and specify it according to the support requirements.

[0086] Step 5: At the end of the fault ride-through, determine the end of the fault ride-through and reset the command values ​​P3(t) and P3(t) of the active power and reactive power.

[0087] Step 5.1: Determine the fault ride-through end time t2.

[0088] If you set the restore to immediate state in step 4:

[0089] t2=t1

[0090] When setting the restore method to slope in step 4:

[0091]

[0092] Step 5.2: Set the power command after the fault ride-through is completed.

[0093] P3(t)=P0,t>t2

[0094] Q3(t)=Q0,t>t2

[0095] Simulations of typical control strategies for energy storage power station fault ride-through were conducted for typical scenarios involving different charge and discharge states, different control strategies, and different power operating levels. The simulated energy storage power station consisted of 100 converters, each with a rated capacity of 1 MVA, for a total power station capacity of 100 MVA. The output power response characteristics of one of the converters were analyzed and compared.

[0096] Attachment Figure 3 The response process of active power and reactive power in a typical fault ride-through process with immediate recovery strategy is shown in the attached figure. Figure 3 (a) is the active power response process, Figure 3 (b) shows the reactive power response process. It can be seen that at the moment of fault ride-through recovery, the active power instantly recovers to the initial power level.

[0097] Attachment Figure 4 Figure 2 is the simulation result of typical fault ride-through process under different power operation levels and different recovery rates under discharge state. Figure 4 (a) is the response process of enhancing active power support during the fault period. It can be seen that during the fault ride-through period, the active power of the energy storage system increased from 0.1 pu before the fault to 0.2 pu, which enhanced the active power support capability of the energy storage system to the system. Figure 4 (b) shows the active power response process of the energy storage system when absorbing surplus power during the fault. Before the fault, the initial active power is 0.5 pu. During the fault, the active power is adjusted to -0.38 pu, switching from the discharge state to the charging state, which helps absorb the system's surplus power.

[0098] Attachment Figure 5 Figure 2 is the simulation result of typical fault ride-through process under different power operation levels and different recovery rates under charging state. Figure 5(a) shows the response process of enhancing active power support during the fault. It can be seen that during the fault ride-through period, the active power of the energy storage system quickly increased from -0.2pu before the fault to 0.6pu, and quickly switched from the charging state to the discharging state, greatly enhancing the active power support capability of the energy storage system for the system. The fault recovery process recovered to the initial power operating level with a negative slope. Figure 5 (b) shows the active power response process of the energy storage system when absorbing surplus power during the fault. Before the fault, the initial active power was -0.2 pu. During the fault, the active power was adjusted to -0.55 pu, which helped to quickly absorb the system's surplus power. The fault recovery process recovered to the initial power operating level with a positive slope.

[0099] The simulation results show that the constructed universal fault ride-through control strategy and program implementation method can be applied to the simulation of typical energy storage power station application scenarios such as different charging and discharging states, different control strategies, and different power operation levels.

[0100] In summary, the method of the present invention has good operability and adaptability, and a simulation model of a universal fault ride-through control strategy suitable for dynamic simulation of large power grids has been constructed, which can support the simulation calculation needs of energy storage systems under different charging and discharging states and different fault ride-through control strategy scenarios.

[0101] Example 2:

[0102] The present invention also proposes a fault ride-through control system 200 for an electrochemical energy storage electromechanical transient model, such as Figure 6 As shown, including:

[0103] Initialization unit 201 is used to record the current active power command value and the current reactive power command value of the electrochemical energy storage system at the start time of the fault ride-through phase under different charge and discharge states and different fault ride-through control strategy scenarios, set the power demand during the fault ride-through phase, and set the fault ride-through recovery process characteristics during the fault ride-through recovery phase;

[0104] A setting unit 202 is configured to determine, after the fault ride-through recovery process characteristics are set, an end time of the fault ride-through end phase based on the recorded current active power command value, current reactive power command value, and set power demand of the electrochemical energy storage system at the end phase of the fault ride-through;

[0105] The control unit 203 is configured to determine a power instruction after the fault ride-through is completed based on the end time, and control the electrochemical energy storage system after the fault with the power instruction.

[0106] The current active power command value and the current reactive power command value of the electrochemical energy storage system recorded by the initial unit 201 are respectively recorded as P0 and Q0;

[0107] Among them, P0 is less than 0 in the charging state and P0 is greater than 0 in the discharging state; the reactive power emitted is Q0 greater than 0 and the reactive power absorbed is Q0 less than 0.

[0108] During the fault ride-through phase, the power demand is set, including:

[0109] An active power instruction P1 is set during the fault ride-through period. When the electrochemical energy storage system lacks active power support during the fault ride-through period, if the electrochemical energy storage system is adjusted to a discharge condition and outputs active power, P1>0; if the electrochemical energy storage system is adjusted to a charge condition and absorbs active power, P1<0;

[0110] The reactive power instruction Q1 is set during the fault ride-through period. When the electrochemical energy storage system lacks reactive power support during the fault ride-through period, if the electrochemical energy storage system is adjusted to output reactive power, Q1>0 at this time; if the electrochemical energy storage system is adjusted to absorb reactive power, Q1<0 at this time.

[0111] During the fault ride-through recovery process, the fault ride-through recovery process characteristics are set, including:

[0112] When the active power recovery mode is set to immediate recovery, the active power instruction of the fault travel recovery process is set to the initial power; when the active power recovery mode is set to recovery according to the slope, the active power instruction value of the fault travel recovery process is calculated in real time;

[0113] Specify reactive power command value according to support requirements.

[0114] When the active power recovery mode is set to immediate recovery, the start time of the fault ride-through recovery process phase is the same as the end time of the fault ride-through end phase.

[0115] The calculation formula for determining the power command after the fault ride-through is completed based on the end time is as follows:

[0116] P3(t)=P0,t>t2

[0117] Q3(t)=Q0,t>t2

[0118] Among them, P3(t) and Q3(t) are the reset active power command value and reactive power command value respectively, P0,t and Q0,t are the initial active power command value and reactive power command value respectively, and t2 is the end time.

[0119] The present invention can support the simulation calculation requirements of point chemical energy storage systems under different charging and discharging states and different fault ride-through control strategy scenarios.

[0120] Example 3:

[0121] Based on the same inventive concept, the present invention also provides a computer device, which includes a processor and a memory, wherein the memory is used to store a computer program, the computer program includes program instructions, and the processor is used to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to implement the corresponding method flow or corresponding function, so as to implement the steps of the method in the above embodiment.

[0122] Example 4:

[0123] Based on the same inventive concept, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It can be understood that the computer-readable storage medium here can include both built-in storage media in the computer device and, of course, extended storage media supported by the computer device. The computer-readable storage medium provides a storage space that stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space. These instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of the method in the above embodiment.

[0124] It will be understood by those skilled in the art that the embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of the present invention may be implemented in various computer languages, for example, the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0125] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0126] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0127] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0128] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0129] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A fault ride-through control method for an electromechanical transient model of electrochemical energy storage, characterized in that: include: Under different charge and discharge states and different fault ride-through control strategy scenarios, at the start of the fault ride-through phase, the current active power command value and the current reactive power command value of the electrochemical energy storage system are recorded. During the fault ride-through phase, the power demand is set. During the fault ride-through recovery phase, the fault ride-through recovery process characteristics are set. After the fault ride-through recovery process characteristics are set, at the end of the fault ride-through phase, the end time of the fault ride-through phase is determined based on the current active power command value, the current reactive power command value, and the set power demand of the electrochemical energy storage system. determining a power instruction after the fault ride-through is completed based on the end time, and controlling the electrochemical energy storage system after the fault with the power instruction; During the fault ride-through phase, the power requirement is set, including: An active power instruction P1 is set during the fault ride-through period. When the electrochemical energy storage system lacks active power support during the fault ride-through period, if the electrochemical energy storage system is adjusted to a discharge condition and outputs active power, P1>0; if the electrochemical energy storage system is adjusted to a charge condition and absorbs active power, P1<0; A reactive power instruction Q1 is set during the fault ride-through period. When the electrochemical energy storage system lacks reactive power support during the fault ride-through period, if the electrochemical energy storage system is adjusted to output reactive power, Q1>0; if the electrochemical energy storage system is adjusted to absorb reactive power, Q1<0; During the fault ride-through recovery process, the fault ride-through recovery process characteristics are set, including: When the active power recovery mode is set to immediate recovery, the active power instruction of the fault travel recovery process is set to the initial power; when the active power recovery mode is set to recovery according to the slope, the active power instruction value of the fault travel recovery process is calculated in real time; Specify reactive power command value according to support requirements; When the active power recovery mode is set to immediate recovery, the start time of the fault ride-through recovery process phase is the same as the end time of the fault ride-through end phase; The calculation formula for determining the power instruction after the fault ride-through is completed based on the end time is as follows: P3(t)=P0,t>t2 Q3(t)=Q0,t>t2 Among them, P3(t) and Q3(t) are the reset active power command value and reactive power command value respectively, P0,t and Q0,t are the initial active power command value and reactive power command value respectively, and t2 is the end time.

2. The method according to claim 1, characterized in that Record the current active power command value and the current reactive power command value of the electrochemical energy storage system, which are recorded as P0 and Q0 respectively; Among them, P0 is less than 0 in the charging state and P0 is greater than 0 in the discharging state; the reactive power emitted is Q0 greater than 0 and the reactive power absorbed is Q0 less than 0.

3. A fault ride-through control system for an electrochemical energy storage electromechanical transient model, characterized in that: include: An initialization unit is used to record the current active power command value and the current reactive power command value of the electrochemical energy storage system at the start time of the fault ride-through phase under different charge and discharge states and different fault ride-through control strategy scenarios, set the power demand during the fault ride-through phase, and set the fault ride-through recovery process characteristics during the fault ride-through recovery phase; A setting unit is configured to determine, after the fault ride-through recovery process characteristics are set, an end time of the fault ride-through end phase based on the recorded current active power command value, current reactive power command value, and set power demand of the electrochemical energy storage system at the end phase of the fault ride-through; a control unit, configured to determine a power instruction after the fault ride-through is completed based on the end time, and control the electrochemical energy storage system after the fault with the power instruction; During the fault ride-through phase, the power requirement is set, including: An active power instruction P1 is set during the fault ride-through period. When the electrochemical energy storage system lacks active power support during the fault ride-through period, if the electrochemical energy storage system is adjusted to a discharge condition and outputs active power, P1>0; if the electrochemical energy storage system is adjusted to a charge condition and absorbs active power, P1<0; A reactive power instruction Q1 is set during the fault ride-through period. When the electrochemical energy storage system lacks reactive power support during the fault ride-through period, if the electrochemical energy storage system is adjusted to output reactive power, Q1>0; if the electrochemical energy storage system is adjusted to absorb reactive power, Q1<0; During the fault ride-through recovery process, the fault ride-through recovery process characteristics are set, including: When the active power recovery mode is set to immediate recovery, the active power instruction of the fault travel recovery process is set to the initial power; when the active power recovery mode is set to recovery according to the slope, the active power instruction value of the fault travel recovery process is calculated in real time; Specify reactive power command value according to support requirements; When the active power recovery mode is set to immediate recovery, the start time of the fault ride-through recovery process phase is the same as the end time of the fault ride-through end phase; The calculation formula for determining the power instruction after the fault ride-through is completed based on the end time is as follows: P3(t)=P0,t>t2 Q3(t)=Q0,t>t2 Among them, P3(t) and Q3(t) are the reset active power command value and reactive power command value respectively, P0,t and Q0,t are the initial active power command value and reactive power command value respectively, and t2 is the end time.

4. The system according to claim 3, characterized in that The current active power command value and the current reactive power command value of the electrochemical energy storage system recorded by the initial unit are recorded as P0 and Q0 respectively; Among them, P0 is less than 0 in the charging state and P0 is greater than 0 in the discharging state; the reactive power emitted is Q0 greater than 0 and the reactive power absorbed is Q0 less than 0.

5. A computer device, characterized in that: include: one or more processors; a processor for executing one or more programs; When the one or more programs are executed by the one or more processors, the method according to any one of claims 1 to 2 is implemented.

6. A computer-readable storage medium, characterized in that A computer program is stored thereon, and when the computer program is executed, the method according to any one of claims 1 to 2 is implemented.

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