CN111459048A - A simulation platform and simulation method for SVG control hardware-in-the-loop - Google Patents

Abstract

The invention provides an SVG control hardware-in-the-loop simulation platform and a simulation method, including: a workstation, an SVG controller and a real-time simulator; Disturbance test of the grid voltage of the sending end system to verify whether the SVG controller is off the grid; the real-time simulator is respectively connected with the workstation and the SVG controller; the workstation is used for the disturbance test based on the grid voltage of the sending end system, and the real-time simulator is issued for the test command; the workstation is also used to obtain the SVG circuit topology model through the real-time simulator to monitor the test based on the test process information executed by the test command; among them, the disturbance test of the grid voltage of the sending end system includes: high voltage ride-through, low voltage ride-through and replacement Phase failure disturbance test; the simulation and reproduction of on-site transient conditions are realized; it is beneficial to grasp the transient operation characteristics of the reactive power compensation device of the new energy base, and propose a reasonable operation control strategy for the new energy grid-connected equipment.

Description

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

technical field

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

Background technique

At present, the fault ride-through control strategy, voltage tolerance capability and reactive power/voltage control strategy of the power generation unit and reactive power compensation device of the existing new energy cluster transmission system have great constraints on the DC transmission capacity, and the DC transmission end grid is weak and supports. Insufficient capacity, DC commutation failure, blocking and other faults can easily cause a large number of power generation units to be chained off the grid. Due to the complex voltage regulation characteristics of wind turbines, photovoltaic power generation units and dynamic reactive power compensation devices, scattered control objectives, and lack of coordinated control, the new energy power generation bases in the actual power grid as a whole show the opposite voltage regulation characteristics of conventional power sources, and the grid adaptability is not strong. For the above problems, it is urgent to study the dynamic characteristics of the reactive power compensation device, and to propose an optimal control strategy to improve the stability of the UHVDC transmission end system in the weak grid.

Considering the advancement of technology, the reactive power compensation devices currently deployed in the AC collection stations of large-scale new energy power generation bases are mainly static reactive power compensation devices SVG, generally including 35kV direct-mounted SVG and 10kV boosted SVG, both of which have a compensation capacity. They are about 30MVar and 10MVar respectively. SVG plays an important role in improving grid output power, grid power factor and suppressing system harmonics. Due to the high voltage level and large compensation capacity at the application site of SVG, a large number of tests and multi-condition tests cannot be carried out on site. Therefore, simulation is required. Means more in-depth research and exploration of SVG transient response characteristics.

SUMMARY OF THE INVENTION

The fault ride-through control strategy, voltage tolerance capability and reactive power/voltage control strategy of the power generation unit and reactive power compensation device of the existing new energy cluster transmission system have great constraints on the DC transmission capacity, and the DC transmission end grid is weak and supports. Insufficient capacity, DC commutation failure, blocking and other faults are likely to cause a large number of power generation units to be disconnected from the grid. The present invention provides a simulation platform and simulation method for SVG control hardware-in-the-loop. The specific steps are as follows:

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 the SVG circuit topology model and model parameters to perform a disturbance test of the grid voltage of the sending end system of the new energy base, and to verify whether the SVG controller is off-grid;

The real-time simulator is respectively connected with the workstation and the SVG controller;

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

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

Preferably, the SVG controller includes a main control device and a valve control device; the simulation platform further includes an optical fiber interface converter;

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

Preferably, the real-time simulator includes: a short-circuit ratio sub-module, a functional sub-module, an I/O port, and a high-speed optical fiber interface;

The short-circuit ratio sub-module is used to change the equivalent impedance of the simulated power grid to obtain different short-circuit ratios of the power system and then obtain different power grid strengths;

The functional sub-module is used to obtain the simulated power grid system voltage/current/SVG current analog quantity and the SVG controller based on the simulated SVG circuit topology model and the different power grid strengths perturbing the power grid voltage of the sending end system. digital switch;

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 for receiving the pulse trigger signal sent by the SVG controller to the model in the simulator, and is also used for real-time The SVG circuit topology model in the simulator transmits 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 simulated by the real-time simulator through the main control device Switch digital in analog and SVG controller to SVG controller.

Preferably, the I/O ports include: SVG switch control signal DI port, SVG switch feedback signal DO port and 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 for receiving the main circuit breaker control signal and the bypass switch control signal issued by the SVG controller;

The DO port of the SVG switch feedback signal is connected to the corresponding port of the main control device of the SVG controller, and is used for sending the status of the main circuit breaker and the status of the bypass switch 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, and 110kV phase current of the SVG circuit topology model in the real-time simulator Signal, SVG phase current to SVG controller.

Preferably, the short-circuit ratio sub-module 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 equivalent inductive reactance of the grid power supply, the equivalent resistance of the grid power supply, 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 configured to calculate a system short circuit ratio based on the system short circuit capacity and the system short circuit capacity.

Preferably, the optical fiber interface converter includes: a signal trigger sub-module and a capacitor-voltage return sub-module;

The signal triggering sub-module is used to convert the low-speed optical fiber into a high-speed optical fiber after parsing and recompiling the low-speed optical fiber of the valve control device to transmit the pulse trigger signal of the SVG controller to the high-speed optical fiber interface. the real-time simulator;

The capacitor voltage return sub-module is used to convert the capacitor voltage signal of the power module of the SVG circuit topology model output by the high-speed optical fiber into a low-speed optical fiber and transmit it to the SVG controller through the low-speed optical fiber interface of the valve control device .

Preferably, the simulation platform further includes an analysis module;

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

Preferably, the analysis module includes: a characteristic parameter calculation sub-module;

The characteristic parameter calculation sub-module is used to simulate the power grid system voltage/current/SVG current analog quantity and the switch digital quantity in the SVG controller based on the different power grid strengths, as well as constant reactive power control or constant voltage control In this 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 power of the SVG device, calculate the output power of the new energy station, calculate the grid power of the sending end system, and calculate the grid connection voltage of the new energy station.

Preferably, the SVG circuit topology model and model parameters are 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 SVG AC Calculation and determination of the number of equivalent levels of the port line voltage.

A simulation method based on SVG control hardware-in-the-loop simulation platform, comprising:

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 of 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 the test process information performed by the SVG controller based on the disturbance experiment, and sends the information to the workstation;

Wherein, the test command issued by the workstation is determined by the workstation based on the disturbance test of the grid voltage of the sending end system; the disturbance test of the grid voltage of the sending end system includes: high voltage ride-through, low voltage ride-through and commutation failure disturbance tests.

Preferably, the real-time simulator simulates the SVG circuit topology model and model parameters to perform a disturbance test of the grid voltage of the sending end system of the new energy base based on the test instruction issued by the workstation, and verifies whether the SVG controller is off-grid, including:

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 then different power grid strengths;

and based on the simulated SVG circuit topology model and the different power grid strengths perturbing the power grid voltage of the sending end system to obtain the simulated power grid system voltage/current/SVG current analog quantity and the switch digital quantity in the SVG controller;

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

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:

The real-time simulator sends the power 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 through 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 the bypass switch of the SVG controller, and obtains the pulse trigger signal fed back by the valve control equipment of the SVG controller through the optical fiber interface converter, and converts the off control commands and pulses. A trigger signal is sent to the workstation.

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

Calculate the short-circuit capacity of the system based on the equivalent inductive reactance of the grid power supply, the equivalent resistance of the grid power supply, the system rated capacity and the 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 system short circuit capacity.

Preferably, the SVG circuit topology model in the real-time simulator transmits the power module capacitor voltage signal to the SVG controller via the 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, including :

After analyzing and recompiling the low-speed optical fiber of the valve control device, the optical fiber interface converter 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 through the high-speed optical fiber interface ;

The optical fiber interface converter converts the power module capacitor voltage signal of the SVG circuit topology model output by the high-speed optical fiber into a low-speed optical fiber and transmits it to the SVG controller through the low-speed optical fiber interface of the valve control device;

Preferably, the method further includes:

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

Preferably, the analysis of the transient reactive power response characteristics of the SVG based on the disturbance test of the grid voltage of the sending end system performed by the real-time simulator includes:

Based on the power grid system voltage/current/SVG current analog quantity and the switch digital quantity in the SVG controller obtained by simulation under the different power grid strengths, and the constant reactive power control or constant voltage control mode, calculate the new energy base sending end system Line loss, calculate the system power of the grid connection point, set the power of the SVG device, calculate the output power of the new energy station, calculate the grid power of the sending end system, and calculate the grid connection voltage of the new energy station.

Preferably, the power grid power of the sending end system is calculated as follows:

为送端系统电网功率，

为并网点系统功率，

为系统线路损耗，

为新能源场站发出的功率，

为SVG装置功率，P_FD为新能源场站有功功率，P_SVG为SVG装置有功功率，Q_FD为SVG装置无功功率，Q_FD为新能源场站无功功率，ΔP_Z、ΔQ_Z分别为系统线路损耗的有功功率和无功功率，P₁、Q₁分别为电网有功功率和电网无功功率。In the formula,

is the grid power of the sending end system,

is the system power of the grid connection point,

is the system line loss,

The power emitted by the new energy station,

is the power of the SVG device, 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 and ΔQ _Z are respectively The active power and reactive power of the system line loss, P ₁ and Q ₁ are the grid active power and grid reactive power, respectively.

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

为新能源场站并网电压，

为风电场并网电压，U₁为新能源基地送端系统理想电网电压，R为系统线路电阻，X为系统线路电抗，R+jX为系统线路等效阻抗；In the formula,

Grid-connected voltage for new energy stations,

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 grid active power P ₁ is:

P ₁ =P _FD -P _SVG -ΔP _Z

The expression of grid reactive power Q ₁ is:

Q ₁ =Q _FD -Q _SVG -ΔQ _Z

Compared with the prior art, the beneficial effects of the present invention are:

1. The present invention provides an SVG control hardware-in-the-loop simulation platform, including: a workstation, an SVG controller and a real-time simulator; the real-time simulator is used to simulate the SVG circuit topology model and model parameters to conduct a new energy base. The disturbance test of the grid voltage of the sending end system to 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 for the disturbance test based on the grid voltage of the sending end system , and issue a test instruction to the real-time simulator; the workstation is further configured to obtain the SVG circuit topology model through the real-time simulator and monitor the test based on the test process information executed by the test instruction; wherein, the The disturbance test of the grid voltage of the sending-end system, including: high voltage ride-through, low voltage ride-through and commutation failure disturbance tests; the simulation and reproduction of on-site transient conditions are realized, and the working conditions of single-machine equipment can be carried out in real time at any time. Simulation;

2. The SVG control hardware-in-the-loop simulation platform and simulation method provided by the present invention provide a simulation analysis tool for analyzing the transient characteristics of the reactive power compensation device of a large-scale new energy base, which is beneficial to grasp the transient characteristics of the reactive power compensation device of the new energy base. According to the state operation characteristics, a reasonable operation control strategy of new energy grid-connected equipment is proposed.

Description of drawings

1 is a schematic diagram of an SVG control hardware-in-the-loop simulation platform provided by the present invention;

Fig. 2 is the topological structure diagram of SVG main circuit provided by the present invention;

FIG. 3 is a circuit topology diagram of a new energy cluster sending system provided by the present invention.

Detailed ways

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

Example 1:

The present application provides an SVG control hardware-in-the-loop simulation platform, which is described with reference to FIG. 1 , and specifically includes:

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

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

Among them, the real-time simulator is used to simulate the SVG circuit topology model and model parameters to conduct the disturbance test of the grid voltage of the sending end system of the new energy base, and to verify whether the SVG controller is disconnected from the grid, including:

The SVG control hardware-in-the-loop simulation platform consists of a test management workstation, a real-time simulator, an optical fiber interface converter and an SVG controller. Among them, the real-time simulator has the functions of real-time operation of mathematical models and real-time I/O port configuration, etc., controls the functional modules in the circuit topology model, and simulates the circuit topology model in Figure 2. Finally, it is downloaded to the simulator through the workstation for operation; the optical fiber interface conversion The controller completes the communication between the SVG valve control device and the simulation platform. It parses and recompiles a large number (hundreds of) low-speed optical fibers of the SVG valve control device through the communication protocol, and converts it into a small amount (usually 1 to 3 pairs) high-speed optical fiber access. The emulator completes data transmission such as power module capacitor voltage and IGBT trigger signal; the SVG controller is a physical device, and its main control device is connected to the emulator to complete the acquisition of analog and digital data, and the valve control device is connected to the optical fiber interface converter to complete the connection. Optical fiber data communication. The simulation platform can perform an overall test of the performance of the SVG controller in all aspects, and can verify the existing software control algorithm, control strategy, equipment performance, and response state of the SVG controller under abnormal working conditions. The problem.

The workstation issues a test instruction to the real-time simulator based on the disturbance test of the grid voltage of the sending-end system; the workstation is further configured to obtain, through the real-time simulator, the test performed by the SVG circuit topology model based on the test instruction Process information monitors the test, including:

The test management workstation is the test host, which realizes the functions of model development, test management, automatic test and graphic monitoring.

Example 2:

This application provides a simulation method based on an SVG control hardware-in-the-loop simulation platform. Taking a 35kV direct-mounted SVG connected to a 110kV sending-end power grid as an example, the simulation method of SVG transient reactive power characteristics based on control hardware-in-the-loop is described. . As shown in Figure 2, in the 35kV direct-mounted SVG main circuit topology, the SVG consists of multiple IGBT rectifier modules connected in series to form a multi-level reactive power unit, which is connected to the device impedance and charging resistance and then connected to the 110kV power grid through a step-up transformer. . The SVG device detects the voltage and current of the grid on the compensation side (35kV or 110kV side), and the control device emits or absorbs reactive power to complete the reactive power compensation function. The SVG reactive power compensation device generally adopts the double closed-loop control structure of the voltage outer loop and the current inner loop. Among them, the voltage outer loop is used to control the DC voltage Udc of the reactive power compensation device, and the current inner loop realizes the reactive current Isvg output of the reactive power compensation device. Usually SVG control mode is divided into constant power mode, constant voltage mode, constant current mode, constant power factor and other modes according to the requirements, including:

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 of the grid voltage of the sending-end system of the new energy base to verify whether the SVG controller is off the grid;

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;

Among them, 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 of the grid voltage of the sending-end system of the new energy base to verify whether the SVG controller is off-grid, including:

(1) SVG transient reactive power response characteristics under different power grid strengths and analysis of its influence on power grid voltage

In the circuit topology of the sending system of the new energy base in Figure 3, the equivalent impedance of the power grid power supply can be changed to obtain different short-circuit ratios of the system, thereby obtaining power grids of different strengths. The invention utilizes the control hardware-in-the-loop simulation platform to observe the transient reactive power response characteristics of the SVG under different power grid strengths, and completes the analysis of the influence of the SVG on the power grid voltage. The specific calculation method of the short-circuit ratio is as follows:

1) Calculation of system short-circuit capacity:

First calculate the equivalent impedance Z _S of the grid power supply:

Among them, Z _L is the equivalent inductive reactance of the grid power supply, and Z _R is the equivalent resistance of the grid power supply.

Then the short-circuit capacity of the system is S _short :

Among them, S _short is the short-circuit capacity of the system, S ₁ is the rated capacity of the system, and U ₁ is the grid voltage of the system.

2) Calculation of the short-circuit capacity of the device S _N :

Among them, _SN is the total capacity of the system power generation units and compensation devices, and _{SN1 , SN2 ...... SNn is the} capacity of each power generation unit and compensation device.

3) Calculate the SCR of the system short-circuit ratio:

When the device capacity S _N is constant, it can be seen from equation (16-17) that Z _L and Z _R are changed, thereby changing the short-circuit capacity S _short of the system to obtain different short-circuit ratios of the system, and then analyze the transient reactive power response of SVG according to different disturbance experiments characteristic. It can be seen from the definition of S _short that it is necessary to change the line impedance value in the simulation model in Figure 3 to complete the experiments with different short-circuit ratios.

(2) Construction method of SVG control hardware-in-the-loop simulation platform

To build the SVG control hardware-in-the-loop simulation platform, the circuit topology in Figure 2 needs to be modeled first. The meanings and determination methods of each parameter in the figure are as follows:

1) Selection of filter reactance L

Consider the capacity and voltage level of the SVG reactive power compensation device to determine the system impedance

According to the empirical value, the short-circuit impedance of the SVG device is generally 10%, so the filter reactance is:

Among them, S _N is the rated capacity of the device, and _{UN is the rated value of the AC line voltage. In this example, UN is 35kV, and ω N is the} power frequency.

2) Power module voltage Udc

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

Wherein, U _{m_N} is the effective value of the DC voltage of a single power module equivalent to 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.

3) Calculation of the number of power modules n

Considering the system redundancy requirements, assuming that the redundancy coefficient is k, the number of power modules is

4) Equivalent switching frequency of SVG AC port

f=n·f _k (5)

Among them, f _k is the switching frequency of the power module.

5) SVG AC port line voltage equivalent level quantity

2n+1 (6)

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

Based on the circuit topology in Figure 2 and the schematic diagram of the simulation platform in Figure 1, the following table describes the interface between the simulator model and the SVG controller. The voltage and current analog quantity between the SVG controller and the switch digital quantity in the SVG controller circuit.

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

(3) Figure 3 is the circuit topology diagram of the new energy cluster sending system. In the figure, U _N is the grid voltage of the new energy power station, U ₁ is the ideal grid voltage of the new energy base sending system, and R and jX are the system line equivalents impedance. The relationship between the voltage U _N of the SVG device and the grid voltage U ₁ of the sending end system is analyzed below.

1) Calculate the system line loss

Among them, Z, R, and X are the equivalent impedance of the system line, the equivalent resistance of the system line, and the equivalent inductance of the system line, respectively, and S ₁ , P ₁ , and Q ₁ are the apparent power, active power, and reactive power of the grid, respectively, ΔP _Z and ΔQ _Z are the active power and reactive power of the system line loss, respectively.

2) Calculate the system power of the grid connection point

Among them, P _N and Q _N are the active power and reactive power of the wind farm, the SVG and the grid connection point, respectively.

3) Assume that the power of the SVG device is

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

4) The power emitted by the new energy station is

Among them, P _FD and Q _FD are the active power and reactive power of the new energy station, respectively.

5) Calculate the grid power of the sending end system

7) Calculate the grid-connected voltage of the new energy station

为风电场并网电压。in,

is the grid-connected voltage of the wind farm.

则上式可简化为because

Then the above formula can be simplified to

P ₁ , Q ₁ can be obtained from Equation 11

P ₁ =P _FD -P _SVG -ΔP _Z (14)

Q ₁ =Q _FD -Q _SVG -ΔQ _Z (15)

Under the ideal power grid, U ₁ remains unchanged. From equations 13, 14, and 15, it can be known that the voltage of the new energy power generation grid is related to the power generated by the power generation unit, the compensation device and the system line impedance.

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, specifically including:

The test management workstation is the test host, which realizes the functions of monitoring the test process;

The simulation platform in the present invention is used for simulation, the grid voltage U1 _of the sending end system is disturbed, and the influence of the grid-connected voltage U _FD of the new energy station is analyzed, so as to observe the difference between the constant reactive power control and constant voltage control of the compensation device SVG in constant reactive power control and constant voltage control. Transient response characteristics in control mode. Generally, the grid voltage U1 disturbance experiment includes three types _: high voltage ride-through, low voltage ride-through and commutation failure. The simulation platform is used to verify whether the SVG controller can not be disconnected from the grid in the above three disturbance experiments, and the SVG controller still works. Then, by modifying the control strategy and adjusting the control parameters, the grid voltage can be beneficially compensated.

As will be appreciated by those skilled in the art, the embodiments of the present application may be provided as a method, a system, or a computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present application. It will be understood that each flow and/or block in the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing device to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing device produce Means for implementing the functions specified in a flow or flow of a flowchart and/or a block or blocks of a block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions The apparatus implements the functions specified in the flow or flow of the flowcharts and/or the block or blocks of the block diagrams.

These computer program instructions can also be loaded on a computer or other programmable data processing device to cause a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process such that The instructions provide steps for implementing the functions specified in the flow or blocks of the flowcharts and/or the block or blocks of the block diagrams.

The above are only examples of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention are included in the application for pending approval of the present invention. within the scope of the claims.

Claims (18)

1. The utility model provides a SVG control hardware is at emulation platform of ring which characterized in that includes: the system comprises a workstation, an SVG controller and a real-time simulator;

the real-time simulator is used for simulating an SVG circuit topology model and model parameters to perform a disturbance test of the grid voltage of a transmitting end system of the new energy base and verifying whether the SVG controller is off-line;

the real-time simulator is respectively connected with the workstation and the SVG controller;

the workstation is used for issuing a test instruction to the real-time simulator based on the disturbance test of the power grid voltage of the sending end system; the workstation is also used for acquiring test process information executed by the SVG circuit topology model based on the test instruction through the real-time simulator to monitor the test;

wherein, the disturbance test of sending end system grid voltage includes: and (3) carrying out perturbation tests on high voltage ride through, low voltage ride through and commutation failure.

2. The simulation platform of claim 1, wherein the SVG controller comprises a master device and a valve control device; the simulation platform further comprises an optical fiber interface converter;

the real-time simulator is connected with the master control equipment of the SVG controller, and the real-time simulator is also connected with the valve control equipment of the SVG controller through an optical fiber interface converter.

3. The simulation platform of claim 2, wherein the real-time simulator comprises: the short-circuit ratio sub-module, the functional sub-module, the I/O port and the high-speed optical fiber interface;

the short-circuit ratio submodule is used for changing the equivalent impedance of the simulated power supply of the power grid to obtain different short-circuit ratios of the power system so as to obtain different power grid strengths;

the function sub-module is used for disturbing the power grid voltage of the transmitting-end system based on the simulated SVG circuit topology model and the different power grid intensities to obtain the simulated power grid system voltage/current/SVG current analog quantity and the switch digital quantity in the SVG controller;

the high-speed optical fiber interface is connected with a low-speed optical fiber interface of valve control equipment of the SVG controller through the optical fiber interface converter, and is used for receiving a pulse trigger signal sent by the SVG controller to a model in the simulator and also used for transmitting a power module capacitance voltage signal to the SVG controller by the SVG circuit topology model in the real-time simulator; and the I/O port is used for transmitting the power grid system voltage/current/SVG current analog quantity and the switch digital quantity in the SVG controller obtained by the simulation of the real-time simulator to the SVG controller through the main control equipment.

4. The emulation platform of claim 3, wherein the I/O port comprises: an SVG switch control signal DI port, an SVG switch feedback signal DO port and an analog signal AO port;

the port of the SVG switch control signal DI is connected with the corresponding port of the main control equipment of the SVG controller and is used for receiving a main circuit breaker control signal and a bypass switch control signal issued by the SVG controller;

the feedback signal DO port of the SVG switch is connected with a corresponding port of a main control device of the SVG controller and used for sending a main breaker state and a bypass switch state returned by a SVG circuit topology model in the real-time simulator to the SVG controller;

the analog signal AO port is connected with a corresponding port of a main control device of the SVG controller and used for sending 35kV line voltage signals, 35kV phase current signals, 110kV line voltage signals, 110kV phase current signals and SVG phase currents of an SVG circuit topology model in the real-time simulator to the SVG controller.

5. The simulation platform of claim 3, wherein the short circuit ratio sub-module comprises: 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 for calculating the system short-circuit capacity based on the equivalent inductive reactance of the power grid power supply, the equivalent resistance of the power grid power supply, the system rated capacity and the system power grid voltage;

the device short-circuit capacity unit is used for calculating the device short-circuit capacity based on the capacities of the power generation units and the compensation device;

the short circuit ratio calculation unit is used for calculating a system short circuit ratio based on the system short circuit capacity and the system short circuit capacity.

6. The emulation platform of claim 3, wherein the fiber optic interface switch comprises: the signal triggering submodule and the capacitor voltage returning submodule;

the signal triggering sub-module is used for converting the low-speed optical fiber into a high-speed optical fiber after analyzing and recompiling the low-speed optical fiber of the valve control equipment, and transmitting a pulse triggering signal of the SVG controller to the real-time simulator through the high-speed optical fiber interface;

and the capacitance voltage feedback sub-module is used for converting a power module capacitance voltage signal of the SVG circuit topology model output by a high-speed optical fiber into a low-speed optical fiber and transmitting the low-speed optical fiber signal to the SVG controller through the low-speed optical fiber interface of the valve control device.

7. The simulation platform of claim 1, further comprising, an analysis module;

and the analysis module is used for analyzing the transient reactive response characteristic of the SVG based on a disturbance test of the grid voltage of the transmitting end system performed by the real-time simulator.

8. The simulation platform of claim 7, wherein the analysis module comprises: a characteristic parameter calculation submodule;

and the characteristic parameter calculation submodule is used for calculating the line loss of a new energy base transmitting system, calculating the power of a grid-connected point system, setting the power of an SVG device, calculating the power emitted by a new energy station, calculating the power of a transmitting system grid and calculating the grid-connected voltage of the new energy station based on the voltage/current/SVG current analog quantity of a power grid system and the switch digital quantity in the SVG controller which are obtained by simulation under different power grid strengths and in a constant reactive power control or constant voltage control mode.

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

10. A simulation method based on an SVG control hardware-in-the-loop simulation platform is characterized by comprising the following steps:

the real-time simulator simulates an SVG circuit topology model and model parameters to perform a disturbance test of the grid voltage of a transmitting end system of the new energy base based on a test instruction issued by the workstation, and verifies whether the SVG controller is off-line;

the real-time simulator receives test process information executed by the SVG controller based on the disturbance experiment and sends the information to the workstation;

the test instruction issued by the workstation is determined by a disturbance test of the workstation based on the grid voltage of the sending end system; the disturbance test of the grid voltage of the sending end system comprises the following steps: and (3) carrying out perturbation tests on high voltage ride through, low voltage ride through and commutation failure.

11. The simulation method of claim 10, wherein the real-time simulator simulates an SVG circuit topology model and model parameters to perform a disturbance test of the grid voltage of the transmitting end system of the new energy base based on test instructions issued by the workstation, and verifies whether the SVG controller is off-line, comprising:

the real-time simulator changes the simulated equivalent impedance of the power supply of the power grid based on a test instruction issued by the workstation to obtain different short-circuit ratios of the power system so as to obtain different power grid strengths;

the simulated power grid system voltage/current/SVG current analog quantity and the switch digital quantity in the SVG controller are obtained based on the simulated SVG circuit topology model and the different power grid intensity disturbance transmitting end system power grid voltages;

and the SVG circuit topology model in the real-time simulator transmits a power module capacitance voltage signal to the SVG controller through the high-speed optical fiber interface, and receives a pulse trigger signal sent by the SVG controller to the model in the simulator through the high-speed optical fiber interface.

12. The simulation method of claim 11, wherein the real-time simulator receives test process information performed by an SVG controller based on the perturbation experiment and sends the information to the workstation, comprising:

the real-time simulator transmits the voltage/current/SVG current analog quantity of the power grid system and the switch digital quantity in the SVG controller to a main control device of the SVG controller through an SVG switch feedback signal DO port and an analog signal AO port;

the real-time simulator acquires a switch control command fed back by a main circuit breaker and a bypass switch of the SVG controller and a pulse trigger signal fed back by a valve control device of the SVG controller through the optical fiber interface converter, and sends the switch control command and the pulse trigger signal to the workstation.

13. The simulation method of claim 11, wherein the real-time simulator changes the simulated equivalent impedance of the power supply of the power grid based on the test instructions issued by the workstation to obtain different short-circuit ratios of the power system and thus different power grid strengths, and comprises:

calculating the short-circuit capacity of the system based on the equivalent inductive reactance of the power grid, the equivalent resistance of the power grid, the rated capacity of the system and the voltage of the system power grid;

calculating device short circuit capacity based on the capacity of each power generation unit and the compensation device;

a system short ratio is calculated based on the system short capacity and the system short capacity.

14. The simulation method of claim 11, wherein the transmitting a power module capacitor voltage signal to the SVG controller by the SVG circuit topology model in the real-time simulator through the high-speed optical fiber interface and receiving a pulse trigger signal issued by the SVG controller to the model in the simulator through the high-speed optical fiber interface comprises:

the optical fiber interface converter analyzes and recompiles the low-speed optical fiber of the valve control equipment, converts the low-speed optical fiber into a high-speed optical fiber, and transmits a pulse trigger signal of the SVG controller to the real-time simulator through the high-speed optical fiber interface;

and the optical fiber interface converter converts the power module capacitance voltage signal of the SVG circuit topology model output by the high-speed optical fiber into a low-speed optical fiber, and the low-speed optical fiber is transmitted to the SVG controller through the low-speed optical fiber interface of the valve control device.

15. The simulation method of claim 10, wherein the method further comprises:

and analyzing the transient reactive response characteristic of the SVG based on the disturbance test of the power grid voltage of the transmitting end system by the real-time simulator.

16. The simulation method of claim 15, wherein the analyzing SVG transient reactive response characteristics based on the disturbance test of the grid voltage of the sending-end system by the real-time simulator comprises:

and calculating the line loss of a new energy base transmitting end system, calculating the power of a grid-connected point system, setting the power of an SVG device, calculating the power of a new energy station, calculating the power of a transmitting end system and calculating the grid-connected voltage of the new energy station under the conditions of the voltage/current/SVG current analog quantity of the power grid system and the switching digital quantity in the SVG controller which are obtained by simulation under different power grid strengths and a constant reactive power control or constant voltage control mode.

17. The simulation method of claim 16, wherein the grid power of the sending-end system is calculated as follows:

in the formula,

for the grid power of the sending-end system,

in order to obtain the power of the point-to-point system,

in order to reduce the line loss of the system,

the power generated by the new energy station,

for SVG device power, P_FDFor active power of new energy stations, P_SVGFor SVG devices active power, Q_FDFor SVG devices reactive power, Q_FDFor reactive power, delta P, of a new energy station_Z、ΔQ_ZActive and reactive power, P, respectively, of system line losses₁、Q₁Respectively the active power and the reactive power of the power grid.

18. The simulation method of claim 16, wherein the grid-connected voltage of the new energy station is calculated by the following formula:

in the formula,

is the grid-connected voltage of the new energy station,

for wind farm grid-connected voltage, U₁For ideal grid voltage of a new energy base sending end system, R is system line resistance, X is system line reactance, and R + jX is system line equivalent impedance;

wherein, the active power P of the power grid₁The expression of (a) is:

P₁＝P_FD-P_SVG-ΔP_Z

reactive power Q of power grid₁The expression of (a) is:

Q₁＝Q_FD-Q_SVG-ΔQ_Z。

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