The Design Of Novel Static Var Compensator

With the development of modern electrical and electronic technology, reactive compensation is not only an important subject touching upon electrical and electronic technology, power system, electrical automation, and theory of Electrical Engineering, etc, but also one of the focus problems in recent years. A novel static device of var compensation is presented in the thesis, based on research of var compensators at home and abroad.The compensation device is shunt static var compensator which includes 4 main parts: main circuit, measuring circuit, control circuit and drive circuit. The main circuit includes parallel fixed compensating capacitor, variable compensating inductor and IGBT, etc. The measuring circuit can achieve real-time reactive power to be compensated by using hardware operations, such as multiplication and summation. The device can realize tracing compensation, because PWM pulse is produced in the control circuit. The electric current and voltage are close to the phase after compensating, namely the power factor is close to 1, so the purpose of dynamic var compensation is achieved.The characteristics in the circuit designed are as follows: IGBT that is used in the main circuit has good improvement at performance than SCR that is used in the past, and number of IGBT used is fewer. Instantaneous reactive power calculated in the measuring circuit is based on instantaneous voltage and instantaneous current value of the supply power line. The calculating method is simple, easy to realize. The control circuit has adopted high optical coupler that makes the main circuit and the control circuit isolate, and has adopted PWM controlling technology. The technology can product less harmonic while tracing compensation reactive power of electric network.The basic principle of the designed device circuit has been simulated through software OrCAD, and simulation experiment has been finished for the experimental device in this thesis. Simulation and experiment show that the basic principle and method are totally feasible and effectual. The device designed with this method is not only suitable for the low-voltage, high-voltage reactive power...