Reactive Power And Voltage Characteristics And Filter Filtering Effect Of Simulation Converter Station

Lingbao back-to back convertor station is the first DC back-to-back project in our country connecting other power systems which is designed, build and constructed by our own technology. It makes the interconnection between Central China and Northwest China power systems into reality, and it's a significant step for the State Grid to take action about the communication among district power systems so as for the whole country and an important method to optimize the resource configuration, improve the operation reliability and obtain great economic profits. In order to get the station to run in stable operation conditions that satisfied, prediction and accordingly resolution about problems that may come out should be brought about in advance. The station's operation has been definitely affected by the harmonic and negative sequence currents from the Lingbao traction substation that built for Zhengxi high-speed rail. Therefore it's meaningful to make simulation on the convertor stationPrimarily the paper analyzes the function of each element in the back-to-back system, builds the equivalent model and parameters on which the construction of convertor main circles, control systems and AC filter model in EMTDC are based. Secondly, the paper makes simulations about the reactive power-voltage features under such circumstances as lower power condition, variation of convertor bus voltage and common faults occurred in rectifiers. After that the curves of DC currents, DC powers and AC bus voltages and reactive power are produced from the simulations. Finally this article finds out the reasons why uncharacteristic harmonics appeared in the station and runs simulations on unbalanced voltage of three phases and asymmetric convertor firing angles (turn-off angles) intervals. Meanwhile it analyzes the effects when the convertor AC filter model works on each filters and verified that the models HP3, HP12/24 performs well.