Design And Realization Of Static Var Generator In The Low Voltage

With the development of power electronic technology, computer technology and theory of control, more and more advanced devices have been implemented in power system. Power system has entered a new stage with ultra-high voltage, long distance and cross-regional networks. The requirements of safety, stability and efficiency are increasing day by day. Reactive power is an important factor to measure power quality. It affects the line loss, voltage drop directly. Recently, Static var Generator (SVG) has become a hot research topic in the field of reactive power compensation. It has been used in the case of high voltage and large capacity. Compared with traditional methods, the main characteristics of SVG are fast response, high precision, smooth adjustment and reliable running. The tendency of SVG technology is facing to low-voltage distribution power system or a special load.In this article, the development of reactive power compensation is introduced and the comparisons of some compensation techniques are given. Secondly, the working principle of SVG and two kinds of equivalent models are introduced in detail, and two kinds of control methods are introduced basing on these equivalent models. Moreover, the mathematical model of SVG, basing on the switching function, is given. Thirdly, several methods of reactive current detection are introduced, and one of them, basing on theory of instantaneous reactive power, is used. Combine the control method with current detection method, the strategy of direct current control is proposed.In this article, the design and manufacture processes of SVG are present in detail. Firstly, a simulation based on MATLAB/Simulink is built. Then, all circuits are designed, including sample module, drive and protection module, main circuit and power supply. Besides, control program are wrote and all program flow chart are given. Finally, the various modules are tested.