Software Design And Implementation Of Reactive Power Compensation Based On H-bridge Cascade STATCOM

Currently,the development status of power system and the application degree of electric energy have become an important index to measure the development level of a country.With the rapid development of national economy and technology,the high precision electrical equipment in the power grid is increasing,and the demand for quality of electric energy in all walks of life is getting higher and higher.Reactive power in the power grid can cause loss of voltage,increase of current,increase of line loss,etc.,and also affect the working condition of other loads.Therefore,it is very important to compensate reactive power in power grid.This article first analyzes the characteristics of the reactive power compensation devices,which includes the thyristor switched capacitor(TSC),thyristor controlled reactor(TCR),static synchronous generator(STATCOM)and so on.And the STATCOM with the H-bridge cascaded is choose to be the research object.According to the requirement of the reactive power compensation,the software system that could satisfy the requirements of real-time,reliability and accuracy is designed.The software system of the STATCOM device includes three parts: a data acquisition unit,a data communication unit,and a host computer humanmachine interaction unit.The function of the data acquisition unit includes controlling the sampling chip to realize the acquisition of information on the grid side,and analyzing and calculating the collected data to obtain the real-time reactive current in the power grid.The data communication unit mainly includes the control of the whole unit of the control unit and the exchange of data in different units.Through the data communication unit,the reactive power data in the power grid is sent to the FPGA chip by the DSP chip.The FPGA chip uses the Carrier phase-shifted SPWM to generate the trigger signal of the IGBT and controls its output to achieve the effect of compensation.In ARM,the embedded system is transplanted,and the overall control of STATCOM device is realized through the application development of Linux platform.At the same time,PC human-computer interaction unit is developed,and the Modbus TCP association is used.The communication between the STATCOM device and the host computer is realized,and the state data in the DSP and FPGA is obtained through the communication unit to realize the display of information in each module,so as to view the operation of the power grid and the STATCOM,and provide the technical guarantee for the safe and reliable operation of the STATCOM device.At last,a test platform to verify the function of STATCOM device is built.The operation reliability,the real-time monitoring data and the correctness of the software are tested.The experimental results show that the software system designed in this paper can be run reliably and can realize compensation for reactive power.Meanwhile,the PC content displays correctly,and effective monitoring of STATCOM can be achieved.