The Research And Realization Of Static Compensator Control Strategy

With the rapid development of the industry in our country, all kinds of precise equipment are used, which put new challenges to the power quality, and the reactive power is one of the important factors which influence voltage stability, so how to implement the effective reactive power compensation is more and more important. As one important device of the flexible AC transmission systems, STATCOM becomes the focus of the study be electric power worker in the world and represents reactive power compensation development trend.Firstly, this paper elaborated the function of reactive compensation and compensation device development, analyses the superiority of STATCOM relative to other reactive power compensation devices, and illustrates the current application and research situation and the development direction of STATCOM. This paper introduces the reactive power dynamic compensation principle, gives a detailed description of the working principle of STATCOM, and on this basis, established a mathematical model of STATCOM and analyses the characteristic of STATCOM. Then, this paper focuses on the two control methods of STATCOM:direct current method and indirect current method, analyses the advantages and disadvantages of the two methods and introduces the application range. Then according to the reactive current detection mode, this paper illustrates the p-q method, the ip-iq method and the d-q method which are based on instantaneous reactive power theory, analyses and compares the characteristics the three methods. This paper establishes the simulation model of STATCOM by MATLAB based on the direct current method and the d-q reactive current detection method, and simulates the capacitive load and inductive load.Based on the above theory, this paper presents a STATCOM experimental apparatus development scheme using FPGA. According to STATCOM requirements, this paper calculates the main circuit component parameters of STATCOM, designs the hardware and software of the control system. In terms of hardware, this paper introduces STATCOM controller structure which has the high precision based on FPGA in detail, designs the controller with the FPGA chips of the high precision, fast speed, strong function and convenient control. And this paper designs some peripheral circuits with the core processor EP2C8Q208C made by the company of Altera, including signal acquisition circuit, zero-crossing comparison circuit, PLL circuit, pulse drive circuit, power supply circuit and protection circuit. In terms of software, this paper gives the specific software design flow chart.