A simulation platform and simulation method for SVG control hardware-in-the-loop

Abstract

The present invention provides a simulation platform and simulation method for SVG control hardware in the loop, comprising: a workstation, an SVG controller and a real-time simulator; the real-time simulator is used to simulate an SVG circuit topology model and model parameters to perform a disturbance test on the power grid voltage of a sending-end system of a new energy base, and verify whether the SVG controller is off-grid; the real-time simulator is connected to the workstation and the SVG controller respectively; the workstation is used to issue test instructions to the real-time simulator based on the disturbance test on the power grid voltage of the sending-end system; the workstation is also used to obtain, through the real-time simulator, test process information of the SVG circuit topology model executed based on the test instructions to monitor the test; wherein, the disturbance test on the power grid voltage of the sending-end system comprises: high voltage ride-through, low voltage ride-through and commutation failure disturbance tests; the simulation and reproduction of on-site transient working conditions are realized; it is conducive to mastering the transient operation characteristics of the reactive compensation device of the new energy base and proposing a reasonable operation control strategy for the new energy grid-connected equipment.

Description

Technical Field

[0001] The present invention belongs to the technical field of electromagnetic transient simulation of an SVG reactive compensation device in a new energy power generation base, and relates to a simulation platform and a simulation method for SVG control hardware in the loop. Background Art

[0002] The fault ride-through control strategies, voltage tolerance, and reactive / voltage control strategies for the power generation units and reactive compensation devices in existing renewable energy cluster transmission systems significantly restrict DC transmission capacity. The DC sending-end grid is weak and lacks sufficient support capacity. Faults such as DC commutation failure and lockout can easily cause a large number of power generation units to disconnect from the grid. Due to the complex voltage regulation characteristics, decentralized control objectives, and lack of coordinated control of wind turbines, photovoltaic power generation units, and dynamic reactive compensation devices, renewable energy power generation bases in actual power grids exhibit voltage regulation characteristics that are opposite to those of conventional power sources, resulting in weak grid adaptability. To address these issues, there is an urgent need to study the dynamic characteristics of reactive compensation devices and propose optimized control strategies to improve the stability of the weak-grid UHVDC sending-end system.

[0003] Considering the advanced technology, the reactive power compensation devices currently deployed at AC collection stations in large-scale renewable energy power generation bases are primarily static VAR devices (SVGs). These typically include 35kV direct-mounted SVGs and 10kV step-up SVGs, with compensation capacities of approximately 30MVar and 10MVar, respectively. SVGs play a crucial role in improving grid output power, improving power factor, and suppressing system harmonics. However, due to the high voltage levels and large compensation capacities of SVGs in their application sites, extensive field testing and multi-condition testing are not feasible. Therefore, simulation is required to further investigate and explore the transient response characteristics of SVGs. Summary of the Invention

[0004] The fault ride-through control strategy, voltage tolerance, and reactive / voltage control strategy of the power generation units and reactive compensation devices in existing new energy cluster transmission systems significantly restrict the DC transmission capacity. The DC transmission end grid is weak and its support capacity is insufficient. Faults such as DC commutation failure and lockout can easily cause a large number of power generation units to disconnect from the grid. This paper proposes a simulation platform and simulation method for SVG control hardware-in-the-loop. The specific steps are as follows:

[0005] A SVG control hardware-in-the-loop simulation platform includes: a workstation, an SVG controller and a real-time simulator;

[0006] The real-time simulator is used to simulate the SVG circuit topology model and model parameters to conduct a disturbance test on the grid voltage of the sending-end system of the new energy base and verify whether the SVG controller is disconnected from the grid;

[0007] The real-time simulator is connected to the workstation and the SVG controller respectively;

[0008] The workstation is used to issue a test instruction to the real-time simulator based on the disturbance test of the sending-end system grid voltage; the workstation is also used to obtain, through the real-time simulator, test process information of the SVG circuit topology model executed based on the test instruction to monitor the test;

[0009] The disturbance test of the sending-end system grid voltage includes: high voltage ride-through, low voltage ride-through and commutation failure disturbance tests.

[0010] Preferably, the SVG controller includes a main control device and a valve control device; the simulation platform also includes a fiber optic interface converter;

[0011] The real-time simulator is connected to the main control device of the SVG controller, and is also connected to the valve control device of the SVG controller via an optical fiber interface converter.

[0012] Preferably, the real-time simulator comprises: a short-circuit ratio submodule, a functional submodule, an I / O port, and a high-speed optical fiber interface;

[0013] The short-circuit ratio submodule is used to change the simulated grid power equivalent impedance to obtain different short-circuit ratios of the power system and thus obtain different grid strengths;

[0014] The functional submodule is configured to obtain the simulated grid system voltage / current / SVG current analog quantity and the switch digital quantity in the SVG controller based on the simulated SVG circuit topology model and the different grid strength disturbance sending-end system grid voltage;

[0015] The high-speed optical fiber interface is connected to the low-speed optical fiber interface of the valve control device of the SVG controller through the optical fiber interface converter, and is used to receive the pulse trigger signal sent by the SVG controller to the model in the simulator, and is also used for the SVG circuit topology model in the real-time simulator to transmit the power module capacitor voltage signal to the SVG controller; the I / O port is used to transmit the power grid system voltage / current / SVG current analog quantity obtained by the real-time simulator and the switch digital quantity in the SVG controller to the SVG controller via the main control device.

[0016] Preferably, the I / O port includes: an SVG switch control signal DI port, an SVG switch feedback signal DO port and an analog signal AO port;

[0017] The SVG switch control signal DI port is connected to the corresponding port of the main control device of the SVG controller, and is used to receive the main circuit breaker control signal and the bypass switch control signal sent by the SVG controller;

[0018] The SVG switch feedback signal DO port is connected to the corresponding port of the main control device of the SVG controller, and is used to send the main circuit breaker status and bypass switch status returned by the SVG circuit topology model in the real-time simulator to the SVG controller;

[0019] The analog signal AO port is connected to the corresponding port of the main control device of the SVG controller, and is used to send the 35kV line voltage signal, 35kV phase current signal, 110kV line voltage signal, 110kV phase current signal, and SVG phase current of the SVG circuit topology model in the real-time simulator to the SVG controller.

[0020] Preferably, the short-circuit ratio submodule includes: a system short-circuit capacity unit, a device short-circuit capacity unit and a short-circuit ratio calculation unit;

[0021] The system short-circuit capacity unit is used to calculate the system short-circuit capacity based on the grid power equivalent inductive reactance, the grid power equivalent resistance, the system rated capacity and the system grid voltage;

[0022] The device short-circuit capacity unit is used to calculate the device short-circuit capacity based on the capacity of each power generation unit and the compensation device;

[0023] The short-circuit ratio calculation unit is configured to calculate the system short-circuit ratio based on the system short-circuit capacity and the system short-circuit capacity.

[0024] Preferably, the optical fiber interface converter includes: a signal trigger submodule and a capacitor voltage feedback submodule;

[0025] The signal trigger submodule is used to parse and recompile the low-speed optical fiber of the valve control device, convert the low-speed optical fiber into a high-speed optical fiber, and transmit the pulse trigger signal of the SVG controller to the real-time simulator via the high-speed optical fiber interface;

[0026] The capacitor voltage feedback submodule is used to convert the capacitor voltage signal of the power module of the SVG circuit topology model output by high-speed optical fiber into low-speed optical fiber and transmit it to the SVG controller via the low-speed optical fiber interface of the valve control device.

[0027] Preferably, the simulation platform further includes an analysis module;

[0028] The analysis module is used to analyze the transient reactive response characteristics of the SVG based on the disturbance test of the sending-end system grid voltage performed by the real-time simulator.

[0029] Preferably, the analysis module includes: a characteristic parameter calculation submodule;

[0030] The characteristic parameter calculation submodule is used to calculate the line loss of the sending-end system of the new energy base, calculate the system power of the grid connection point, set the power of the SVG device, calculate the power emitted by the new energy station, calculate the power of the sending-end system grid, and calculate the grid connection voltage of the new energy station based on the grid system voltage / current / SVG current analog values ​​simulated under the different grid strengths and the switch digital values ​​in the SVG controller, as well as under constant reactive power control or constant voltage control mode.

[0031] Preferably, the SVG circuit topology model and model parameters are determined based on the selection of filter reactance, the determination of the conversion relationship between the power module and the AC line voltage, the calculation of the number of power modules, the calculation of the equivalent switching frequency of the SVG AC port, and the calculation of the number of equivalent levels of the SVG AC port line voltage.

[0032] A simulation method based on an SVG controlled hardware-in-the-loop simulation platform, comprising:

[0033] Based on the test instructions issued by the workstation, the real-time simulator simulates the SVG circuit topology model and model parameters to conduct a disturbance test on the grid voltage of the sending-end system of the new energy base to verify whether the SVG controller is disconnected from the grid;

[0034] The real-time simulator receives test process information performed by the SVG controller based on the disturbance experiment and sends the information to the workstation;

[0035] Among them, the test instructions issued by the workstation are determined by the workstation based on the disturbance test of the sending-end system grid voltage; the disturbance test of the sending-end system grid voltage includes: high voltage ride-through, low voltage ride-through and commutation failure disturbance tests.

[0036] Preferably, the real-time simulator simulates the SVG circuit topology model and model parameters based on the test instructions issued by the workstation to perform a disturbance test on the grid voltage of the sending-end system of the new energy base to verify whether the SVG controller is disconnected from the grid, including:

[0037] Based on the test instructions issued by the workstation, the real-time simulator changes the equivalent impedance of the simulated power grid to obtain different short-circuit ratios of the power system and thus different power grid strengths;

[0038] and obtaining the simulated grid system voltage / current / SVG current analog quantity and the switch digital quantity in the SVG controller based on the simulated SVG circuit topology model and the different grid strength disturbance sending-end system grid voltage;

[0039] The SVG circuit topology model in the real-time simulator transmits the power module capacitor voltage signal to the SVG controller via a high-speed optical fiber interface, and receives the pulse trigger signal sent by the SVG controller to the model in the simulator via the high-speed optical fiber interface.

[0040] Preferably, the real-time simulator receives the test process information performed by the SVG controller based on the disturbance experiment and sends the information to the workstation, including:

[0041] The real-time simulator sends the grid system voltage / current / SVG current analog quantity and the switch digital quantity in the SVG controller to the main control device of the SVG controller via the SVG switch feedback signal DO port and the analog signal AO port;

[0042] The real-time simulator obtains the switch control commands fed back by the main circuit breaker and bypass switch of the SVG controller and the pulse trigger signal fed back by the valve control device of the SVG controller through the optical fiber interface converter, and sends the switch control commands and pulse trigger signal to the workstation.

[0043] Preferably, the real-time simulator changes the simulated grid power equivalent impedance based on the test instructions issued by the workstation to obtain different short-circuit ratios of the power system and thus obtain different grid strengths, including:

[0044] Calculate the system short-circuit capacity based on the grid power equivalent inductive reactance, grid power equivalent resistance, system rated capacity and system grid voltage;

[0045] Calculate the short-circuit capacity of the device based on the capacity of each power generation unit and compensation device;

[0046] A system short circuit ratio is calculated based on the system short circuit capacity and the system short circuit capability.

[0047] Preferably, the SVG circuit topology model in the real-time simulator transmits a power module capacitor voltage signal to the SVG controller via a high-speed optical fiber interface, and receives a pulse trigger signal sent by the SVG controller to the model in the simulator via the high-speed optical fiber interface, including:

[0048] The optical fiber interface converter parses and recompiles the low-speed optical fiber of the valve control device, converts the low-speed optical fiber into a high-speed optical fiber, and transmits the pulse trigger signal of the SVG controller to the real-time simulator via the high-speed optical fiber interface;

[0049] The optical fiber interface converter converts the power module capacitor voltage signal of the SVG circuit topology model outputted via high-speed optical fiber into a low-speed optical fiber and transmits the signal to the SVG controller via the low-speed optical fiber interface of the valve control device;

[0050] Preferably, the method further comprises:

[0051] Based on the disturbance test of the sending-end system grid voltage carried out by the real-time simulator, the transient reactive power response characteristics of the SVG are analyzed.

[0052] Preferably, the disturbance test of the sending-end system grid voltage performed based on the real-time simulator to analyze the transient reactive response characteristics of the SVG includes:

[0053] Based on the grid system voltage / current / SVG current analog values ​​obtained by simulation under the different grid strengths and the switch digital values ​​in the SVG controller, as well as under constant reactive power control or constant voltage control mode, the line loss of the sending-end system of the new energy base is calculated, the system power of the grid connection point is calculated, the power of the SVG device is set, the power emitted by the new energy station is calculated, the grid power of the sending-end system is calculated, and the grid connection voltage of the new energy station is calculated.

[0054] Preferably, the power of the sending-end system grid is calculated as follows:

[0055]

[0056] Where, is the power of the sending-end system grid, is the grid-connected point system power, is the system line loss, The power generated by the new energy station, is the SVG device power, P FD is the active power of the new energy station, P SVG is the active power of the SVG device, Q FD is the reactive power of the SVG device, Q FD is the reactive power of the new energy station, ΔP Z , ΔQ Z are the active power and reactive power of the system line loss, P1 and Q1 are the grid active power and grid reactive power, respectively.

[0057] Preferably, the grid-connected voltage of the new energy station is calculated as follows:

[0058]

[0059] Where, is the grid-connected voltage of the new energy station, is the grid-connected voltage of the wind farm, U1 is the ideal grid voltage of the sending-end system of the new energy base, R is the system line resistance, X is the system line reactance, and R+jX is the system line equivalent impedance;

[0060] Among them, the expression of the grid active power P1 is:

[0061] P1=P FD -P SVG -ΔP Z

[0062] The expression of grid reactive power Q1 is:

[0063] Q1=Q FD -Q SVG -ΔQ Z

[0064] Compared with the prior art, the present invention has the following beneficial effects:

[0065] 1. The present invention provides an SVG control hardware-in-the-loop simulation platform, comprising: a workstation, an SVG controller, and a real-time simulator; the real-time simulator is used to simulate an SVG circuit topology model and model parameters to perform a disturbance test on the grid voltage of the sending-end system of a new energy base and verify whether the SVG controller is off-grid; the real-time simulator is connected to the workstation and the SVG controller respectively; the workstation is used to issue a test instruction to the real-time simulator based on the disturbance test on the grid voltage of the sending-end system; the workstation is also used to obtain, through the real-time simulator, information on the test process executed by the SVG circuit topology model based on the test instruction to monitor the test; wherein, the disturbance test on the grid voltage of the sending-end system includes: high voltage ride-through, low voltage ride-through, and commutation failure disturbance test; the simulation and reproduction of on-site transient operating conditions are realized, and the operating conditions of a single device can be simulated and verified in real time at any time;

[0066] 2. The present invention provides an SVG control hardware-in-the-loop simulation platform and simulation method, which provides a simulation analysis tool for analyzing the transient characteristics of reactive power compensation devices in large-scale new energy bases. This is conducive to understanding the transient operating characteristics of reactive power compensation devices in new energy bases and proposing reasonable operation control strategies for new energy grid-connected equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 Schematic diagram of the SVG control hardware-in-the-loop simulation platform provided by the present invention;

[0068] Figure 2 This is the topological structure diagram of the SVG main circuit provided by the present invention;

[0069] Figure 3 This is the circuit topology diagram of the new energy cluster transmission system provided by the present invention. DETAILED DESCRIPTION

[0070] The embodiments of the present invention will be further described with reference to the accompanying drawings.

[0071] Example 1:

[0072] This application provides a SVG control hardware-in-the-loop simulation platform, combined with Figure 1 Provide a description, including:

[0073] A real-time simulator is used to simulate the SVG circuit topology model and model parameters to conduct disturbance tests on the sending-end system grid voltage of the new energy base and verify whether the SVG controller is disconnected from the grid;

[0074] The workstation is used to issue a test instruction to the real-time simulator based on the disturbance test of the sending-end system grid voltage; the workstation is also used to obtain, through the real-time simulator, test process information of the SVG circuit topology model executed based on the test instruction to monitor the test;

[0075] The real-time simulator is used to simulate the SVG circuit topology model and model parameters to conduct disturbance tests on the grid voltage of the sending-end system of the new energy base and verify whether the SVG controller is disconnected from the grid. Specifically, it includes:

[0076] The SVG control hardware-in-the-loop simulation platform consists of a test management workstation, a real-time simulator, a fiber optic interface converter, and an SVG controller. The real-time simulator has the functions of real-time operation of mathematical models and real-time I / O port configuration, and controls the functional modules in the circuit topology model to simulate Figure 2 The circuit topology model is ultimately downloaded to the simulator via a workstation and executed. A fiber optic interface converter facilitates communication between the SVG valve control device and the simulation platform. It parses and recompiles the SVG valve control device's numerous (hundreds) low-speed optical fibers through a communication protocol, converting them into a small number (typically one to three pairs) of high-speed optical fibers connected to the simulator for data transmission, including power module capacitor voltages and IGBT trigger signals. The SVG controller is a physical device; its main control device connects to the simulator to collect analog and digital data, while the valve control device connects to the fiber optic interface converter for optical data communication. This simulation platform allows comprehensive testing of all aspects of the SVG controller's performance, verifying the controller's existing software control algorithms, control strategies, device performance, and response to abnormal operating conditions, enabling timely identification of controller issues.

[0077] The workstation issues a test instruction to the real-time simulator based on the disturbance test of the sending-end system grid voltage. The workstation is further configured to obtain, through the real-time simulator, test process information of the SVG circuit topology model executed based on the test instruction to monitor the test, specifically including:

[0078] The test management workstation is the test host, which realizes functions such as model development, test management, automatic testing and graphic monitoring.

[0079] Example 2:

[0080] This application provides a simulation method based on SVG control hardware-in-the-loop simulation platform. Taking 35kV direct-mounted SVG connected to 110kV sending-end power grid as an example, the simulation method of SVG transient reactive characteristics based on control hardware-in-the-loop is described. Figure 2 As shown in the figure, in the main circuit topology of a 35kV direct-mounted SVG, the SVG consists of multiple IGBT rectifier modules connected in series to form a multi-level reactive power unit. After being connected to the device impedance and charging resistor, it is connected to the 110kV grid via a step-up transformer. The SVG device detects the grid voltage and current on the compensation side (35kV or 110kV side) and controls the device to emit or absorb reactive power to complete the reactive compensation function. SVG reactive compensation devices generally adopt a dual closed-loop control structure with a voltage outer loop and a current inner loop. The voltage outer loop is used to control the DC voltage Udc of the reactive compensation device, while the current inner loop realizes the reactive current Isvg output of the reactive compensation device. Generally, SVG control modes are divided into constant power mode, constant voltage mode, constant current mode, constant power factor mode, etc. according to demand, specifically including:

[0081] Step 1: Based on the test instructions issued by the workstation, the real-time simulator simulates the SVG circuit topology model and model parameters to conduct a disturbance test on the sending-end system grid voltage of the new energy base to verify whether the SVG controller is disconnected from the grid;

[0082] Step 2: The real-time simulator receives the test process information performed by the SVG controller based on the disturbance experiment, and sends the information to the workstation;

[0083] Step 1: Based on the test instructions issued by the workstation, the real-time simulator simulates the SVG circuit topology model and model parameters to conduct a disturbance test on the grid voltage of the sending-end system of the new energy base to verify whether the SVG controller is disconnected from the grid. Specifically, the test includes:

[0084] (1) Analysis of SVG transient reactive response characteristics and its impact on grid voltage under different grid strengths

[0085] exist Figure 3 In the circuit topology of a new energy base transmission system, varying the equivalent impedance of the grid power source can yield different short-circuit ratios, thereby creating grids of varying strengths. This paper utilizes a control hardware-in-the-loop simulation platform to observe the transient reactive power response characteristics of SVG under varying grid strengths, analyzing its impact on grid voltage. The specific method for calculating the short-circuit ratio is as follows:

[0086] 1) Calculation of system short-circuit capacity:

[0087] First calculate the equivalent impedance Z of the power grid S :

[0088]

[0089] Among them, Z L is the equivalent inductive reactance of the grid power supply, Z R is the equivalent resistance of the power grid.

[0090] Then the system short-circuit capacity is S short :

[0091]

[0092] Among them, S short is the system short-circuit capacity, S1 is the system rated capacity, and U1 is the system grid voltage.

[0093] 2) Calculation of short-circuit capacity of the device S N :

[0094]

[0095] Among them, S N is the total capacity of the system power generation unit and compensation device, S N1 、S N2 ......S Nn The capacity of each power generation unit and compensation device.

[0096] 3) System short circuit ratio calculation SCR:

[0097]

[0098] When the device capacity S N From formula (16-17), we can know that changing Z L and Z R , thereby changing the system short-circuit capacity S short , different system short-circuit ratios are obtained, and then the transient reactive response characteristics of SVG are analyzed according to different disturbance experiments. short The definition of Figure 3 The line impedance values ​​in the simulation model were used to complete experiments with different short-circuit ratios.

[0099] (2) Method for building SVG control hardware-in-the-loop simulation platform

[0100] To build an SVG control hardware-in-the-loop simulation platform, you first need to Figure 2 The circuit topology is modeled. The meaning and determination methods of each parameter in the figure are as follows:

[0101] 1) Selection of filter reactance L

[0102] Considering the capacity and voltage level of the SVG reactive compensation device, determine the system impedance

[0103]

[0104] According to empirical values, the short-circuit impedance of SVG is generally set at 10%, so the filter reactance is:

[0105]

[0106] Among them, S N is the rated capacity of the device, U N AC line voltage rating, in this case U N is 35kV, ω N For the industrial frequency.

[0107] 2) Power module voltage Udc

[0108] The conversion relationship between the power module and the AC line voltage is:

[0109]

[0110] Among them, U m_N The DC voltage of a single power module is equivalent to the effective value of the AC line voltage, U dc_n is the nominal voltage of the DC capacitor of a single power module, M is the modulation ratio, and M<1.

[0111] 3) Calculation of the number of power modules n

[0112] Considering the system redundancy requirements, assuming the redundancy coefficient is k, the number of power modules is

[0113]

[0114] 4) SVG AC port equivalent switching frequency

[0115] f=n·f k (5)

[0116] Among them, f k is the power module switching frequency.

[0117] 5) Number of SVG AC port line voltage equivalent levels

[0118] 2n+1 (6)

[0119] According to the above calculation results, the SVG circuit topology is modeled and the model parameters are determined. The model is finally downloaded to the real-time simulator to complete the control hardware-in-the-loop simulation test.

[0120] based on Figure 2 Circuit topology and Figure 1The following table describes the interface between the simulator model and the SVG controller. The interface names, types, and quantities vary for different controllers and application scenarios. These interfaces include analog voltage and current between the grid and the SVG controller, as well as digital switches within the SVG controller circuit.

[0121] Table 1 SVG control-in-the-loop simulation platform interface table

[0122]

[0123]

[0124] (3) Figure 3 This is the circuit topology diagram of the new energy cluster transmission system. In the figure, U N is the grid voltage of the new energy power station, U1 is the ideal grid voltage of the new energy base sending end system, R and jX are the equivalent impedance of the system line. N Relationship with the sending end system grid voltage U1.

[0125] 1) Calculate system line loss

[0126]

[0127] Among them, Z, R, and X are the equivalent impedance, equivalent resistance, and equivalent inductive reactance of the system line, respectively; S1, P1, and Q1 are the apparent power, active power, and reactive power of the grid, respectively; ΔP Z , ΔQ Z are the active power and reactive power of system line loss respectively.

[0128] 2) Calculate the system power at the grid connection point

[0129]

[0130] Among them, P N , Q N They are the active power and reactive power of the wind farm, SVG and grid connection point respectively.

[0131] 3) Assume that the SVG device power is

[0132]

[0133] Among them, P SVG , Q SVG are the active power and reactive power of the SVG device respectively.

[0134] 4) The power generated by the new energy station is

[0135]

[0136] Among them, P FD , Q FD They are the active power and reactive power of the new energy station respectively.

[0137] 5) Calculate the power of the sending system grid

[0138]

[0139] 7) Calculate the grid-connected voltage of new energy stations

[0140]

[0141] in, is the grid-connected voltage of the wind farm.

[0142] because The above formula can be simplified to

[0143]

[0144] P1 and Q1 can be obtained from formula 11

[0145] P1=P FD -P SVG -ΔP Z (14)

[0146] Q1=Q FD -Q SVG -ΔQ Z (15)

[0147] Under an ideal power grid, U1 remains unchanged. It can be seen from Equations 13, 14, and 15 that the voltage of the renewable energy power generation grid is related to the power generated by the power generation unit, compensation device, and system line impedance.

[0148] Step 2: The real-time simulator receives the test process information executed by the SVG controller based on the disturbance experiment and sends the information to the workstation, specifically including:

[0149] The test management workstation is the test host, which realizes functions such as monitoring of the test process;

[0150] The simulation platform of the present invention is used to simulate and disturb the grid voltage U1 of the sending end system, and analyze the grid voltage U1 of the new energy station. FDThis allows for observation of the transient response characteristics of the compensation device SVG under different control modes, such as constant reactive power control and constant voltage control. Common grid voltage U1 disturbance tests include high voltage ride-through, low voltage ride-through, and commutation failure. The simulation platform verifies whether the SVG controller can maintain grid operation during these three disturbance tests without disconnecting from the grid. Furthermore, by modifying the control strategy and adjusting the control parameters, beneficial compensation for the grid voltage can be achieved.

[0151] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0152] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, 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 steps in the process. 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.

[0153] 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.

[0154] 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.

[0155] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. An SVG control hardware-in-the-loop simulation platform, characterized in that: include: Workstations, SVG controllers, and real-time simulators; The real-time simulator is used to simulate the SVG circuit topology model and model parameters to conduct a disturbance test on the grid voltage of the sending-end system of the new energy base and verify whether the SVG controller is disconnected from the grid; The real-time simulator is connected to the workstation and the SVG controller respectively; The workstation is used to issue a test instruction to the real-time simulator based on the disturbance test of the sending-end system grid voltage; the workstation is also used to obtain, through the real-time simulator, test process information of the SVG circuit topology model executed based on the test instruction to monitor the test; The disturbance test of the sending-end system grid voltage includes: high voltage ride-through, low voltage ride-through and commutation failure disturbance test; The real-time simulator includes: a short-circuit ratio submodule, a functional submodule, an I / O port, and a high-speed optical fiber interface; The short-circuit ratio submodule is used to change the simulated grid power equivalent impedance to obtain different short-circuit ratios of the power system and thus obtain different grid strengths; The functional submodule is configured to obtain the simulated grid system voltage / current / SVG current analog quantity and the switch digital quantity in the SVG controller based on the simulated SVG circuit topology model and the different grid strength disturbance sending-end system grid voltage; Also included is, an analysis module; The analysis module is used to analyze the transient reactive response characteristics of the SVG based on the disturbance test of the sending-end system grid voltage performed by the real-time simulator; The analysis module includes: a characteristic parameter calculation submodule; The characteristic parameter calculation submodule is used to calculate the line loss of the sending-end system of the new energy base, calculate the system power of the grid connection point, set the power of the SVG device, calculate the power emitted by the new energy station, calculate the power of the sending-end system grid, and calculate the grid connection voltage of the new energy station based on the grid system voltage / current / SVG current analog values ​​obtained by simulation under the different grid strengths and the switch digital values ​​in the SVG controller, and under the constant reactive power control or constant voltage control mode; The power of the sending-end system grid is calculated as follows: Where, is the power of the sending-end system grid, is the grid-connected point system power, is the system line loss, The power generated by the new energy station, is the SVG device power, P FD is the active power of the new energy station, P SVG is the active power of the SVG device, Q FD is the reactive power of the SVG device, Q FD is the reactive power of the new energy station, △P Z , △Q Z are the active power and reactive power of the system line loss, P1 and Q1 are the grid active power and grid reactive power respectively; The grid-connected voltage of the new energy station is calculated as follows: Where, is the grid-connected voltage of the new energy station, is the grid-connected voltage of the wind farm, U1 is the ideal grid voltage of the sending-end system of the new energy base, R is the system line resistance, X is the system line reactance, and R+jX is the system line equivalent impedance; Among them, the expression of the grid active power P1 is: P1=P FD -P SVG -ΔP Z The expression of grid reactive power Q1 is: Q1=Q FD -Q SVG -ΔQ Z 。 2. The simulation platform according to claim 1, wherein: The SVG controller includes a main control device and a valve control device; the simulation platform also includes a fiber optic interface converter; The real-time simulator is connected to the main control device of the SVG controller, and is also connected to the valve control device of the SVG controller via an optical fiber interface converter.

3. The simulation platform according to claim 2, wherein: The high-speed optical fiber interface is connected to the low-speed optical fiber interface of the valve control device of the SVG controller through the optical fiber interface converter, and is used to receive the pulse trigger signal sent by the SVG controller to the model in the simulator, and is also used for the SVG circuit topology model in the real-time simulator to transmit the power module capacitor voltage signal to the SVG controller; the I / O port is used to transmit the power grid system voltage / current / SVG current analog quantity obtained by the real-time simulator and the switch digital quantity in the SVG controller to the SVG controller via the main control device.

4. The simulation platform according to claim 3, wherein: The I / O ports include: an SVG switch control signal DI port, an SVG switch feedback signal DO port, and an analog signal AO port; The SVG switch control signal DI port is connected to the corresponding port of the main control device of the SVG controller, and is used to receive the main circuit breaker control signal and bypass switch control signal sent by the SVG controller; The SVG switch feedback signal DO port is connected to the corresponding port of the main control device of the SVG controller, and is used to send the main circuit breaker status and bypass switch status returned by the SVG circuit topology model in the real-time simulator to the SVG controller; The analog signal AO port is connected to the corresponding port of the main control device of the SVG controller, and is used to send the 35kV line voltage signal, 35kV phase current signal, 110kV line voltage signal, 110kV phase current signal, and SVG phase current of the SVG circuit topology model in the real-time simulator to the SVG controller.

5. The simulation platform according to claim 3, wherein: The short-circuit ratio submodule includes: a system short-circuit capacity unit, a device short-circuit capacity unit and a short-circuit ratio calculation unit; The system short-circuit capacity unit is used to calculate the system short-circuit capacity based on the grid power equivalent inductive reactance, the grid power equivalent resistance, the system rated capacity and the system grid voltage; The device short-circuit capacity unit is used to calculate the device short-circuit capacity based on the capacity of each power generation unit and the compensation device; The short-circuit ratio calculation unit is used to calculate the system short-circuit ratio based on the system short-circuit capacity and the device short-circuit capacity.

6. The simulation platform according to claim 3, wherein: The optical fiber interface converter includes: a signal trigger submodule and a capacitor voltage feedback submodule; The signal trigger submodule is used to parse and recompile the low-speed optical fiber of the valve control device, convert the low-speed optical fiber into a high-speed optical fiber, and transmit the pulse trigger signal of the SVG controller to the real-time simulator via the high-speed optical fiber interface; The capacitor voltage feedback submodule is used to convert the capacitor voltage signal of the power module of the SVG circuit topology model output by high-speed optical fiber into low-speed optical fiber and transmit it to the SVG controller via the low-speed optical fiber interface of the valve control device.

7. The simulation platform according to claim 1, wherein: The SVG circuit topology model and model parameters are determined based on the selection of filter reactance, the determination of the conversion relationship between the power module and the AC line voltage, the calculation of the number of power modules, the calculation of the equivalent switching frequency of the SVG AC port, and the calculation of the number of equivalent levels of the SVG AC port line voltage.

8. A simulation method based on SVG control hardware-in-the-loop simulation platform, characterized in that: include: Based on the test instructions issued by the workstation, the real-time simulator simulates the SVG circuit topology model and model parameters to conduct a disturbance test on the grid voltage of the sending-end system of the new energy base to verify whether the SVG controller is disconnected from the grid; The real-time simulator receives test process information executed by the SVG controller based on the disturbance test and sends the information to the workstation; The test instructions issued by the workstation are determined by the workstation based on a disturbance test of the sending-end system grid voltage; the disturbance test of the sending-end system grid voltage includes: high voltage ride-through, low voltage ride-through and commutation failure disturbance tests; The real-time simulator simulates the SVG circuit topology model and model parameters based on the test instructions issued by the workstation to perform a disturbance test on the power grid voltage of the sending-end system of the new energy base to verify whether the SVG controller is disconnected from the grid, including: the real-time simulator changes the simulated power grid power equivalent impedance based on the test instructions issued by the workstation to obtain different short-circuit ratios of the power system and thus obtain different power grid strengths; and obtaining the simulated grid system voltage / current / SVG current analog quantity and the switch digital quantity in the SVG controller based on the simulated SVG circuit topology model and the different grid strength disturbance sending-end system grid voltage; The method further comprises: Analyze the transient reactive power response characteristics of SVG based on the disturbance test of the sending-end system grid voltage conducted by the real-time simulator; The disturbance test of the sending-end system grid voltage based on the real-time simulator and the analysis of the transient reactive power response characteristics of the SVG include: Based on the grid system voltage / current / SVG current analog values ​​obtained by simulation under the different grid strengths and the switch digital values ​​in the SVG controller, and under constant reactive power control or constant voltage control mode, calculate the line loss of the sending-end system of the new energy base, calculate the system power of the grid connection point, set the SVG device power, calculate the power emitted by the new energy station, calculate the grid power of the sending-end system, and calculate the grid connection voltage of the new energy station; The power of the sending-end system grid is calculated as follows: Where, is the power of the sending-end system grid, is the grid-connected point system power, is the system line loss, The power generated by the new energy station, is the SVG device power, P FD is the active power of the new energy station, P SVG is the active power of the SVG device, Q FD is the reactive power of the SVG device, Q FD is the reactive power of the new energy station, △P Z , △Q Z are the active power and reactive power of the system line loss, P1 and Q1 are the grid active power and grid reactive power respectively; The grid-connected voltage of the new energy station is calculated as follows: Where, is the grid-connected voltage of the new energy station, is the grid-connected voltage of the wind farm, U1 is the ideal grid voltage of the sending-end system of the new energy base, R is the system line resistance, X is the system line reactance, and R+jX is the system line equivalent impedance; Among them, the expression of the grid active power P1 is: P1=P FD -P SVG -ΔP Z The expression of grid reactive power Q1 is: Q1=Q FD -Q SVG -ΔQ Z 。 9. The simulation method according to claim 8, wherein: The real-time simulator simulates the SVG circuit topology model and model parameters based on the test instructions issued by the workstation to perform a disturbance test on the grid voltage of the sending-end system of the new energy base to verify whether the SVG controller is disconnected from the grid. The real-time simulator also includes: The SVG circuit topology model in the real-time simulator transmits the power module capacitor voltage signal to the SVG controller via a high-speed optical fiber interface, and receives the pulse trigger signal sent by the SVG controller to the model in the simulator via the high-speed optical fiber interface.

10. The simulation method according to claim 9, wherein: The real-time simulator receives test process information executed by the SVG controller based on the disturbance test and sends the information to the workstation, including: The real-time simulator sends the grid system voltage / current / SVG current analog quantity and the switch digital quantity in the SVG controller to the main control device of the SVG controller via the SVG switch feedback signal DO port and the analog signal AO port; The real-time simulator obtains the switch control commands fed back by the main circuit breaker and bypass switch of the SVG controller and the pulse trigger signal fed back by the valve control device of the SVG controller through the optical fiber interface converter, and sends the switch control commands and pulse trigger signal to the workstation.

11. The simulation method according to claim 9, wherein: The real-time simulator changes the simulated grid power equivalent impedance based on the test instructions issued by the workstation to obtain different short-circuit ratios of the power system and thus different grid strengths, including: Calculate the system short-circuit capacity based on the grid power equivalent inductive reactance, grid power equivalent resistance, system rated capacity and system grid voltage; Calculate the short-circuit capacity of the device based on the capacity of each power generation unit and compensation device; A system short circuit ratio is calculated based on the system short circuit capacity and the device short circuit capacity.

12. The simulation method according to claim 10, wherein: The SVG circuit topology model in the real-time simulator transmits a power module capacitor voltage signal to the SVG controller via a high-speed optical fiber interface, and receives a pulse trigger signal sent by the SVG controller to the model in the simulator via the high-speed optical fiber interface, including: The optical fiber interface converter parses and recompiles the low-speed optical fiber of the valve control device, converts the low-speed optical fiber into a high-speed optical fiber, and transmits the pulse trigger signal of the SVG controller to the real-time simulator via the high-speed optical fiber interface; The optical fiber interface converter converts the power module capacitor voltage signal of the SVG circuit topology model outputted via high-speed optical fiber into a low-speed optical fiber and transmits the signal to the SVG controller via the low-speed optical fiber interface of the valve control device.

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