Study On Three-phase Static Synchronous Compensator With Direct Current Control

With the rapid development of national economy, reactive power compensationis not enough in industry and civil. The phenomenon is more and more serious, thatreactive power compensation device falls behind the development of power system.The traditional reactive power compensation can’t satisfy requesting in modernizedpower enterprises. The perspective of the study on reactive power theory and theresearch on reactive power compensation device is considerable. Static synchronouscompensator (STATCOM) is the most advanced compensation device. It not onlycan realize the dynamic compensation for power grid, but also plays an importantrole in reducing harmful currents.This dissertation analyzes the development of STATCOM and the updatingpresent situation of its control technology in details. The actual working process ofSTATCOM with three-phase voltage source is analyzed and simulated in detail. Thetriangle wave compare control is chosen for the feasibility and correctness ofSTATCOM. The dq0coordination transformation is also adopted, which is based onthe instantaneous reactive power theory.Simulation model are built in Matlab and the performance is analyzed. Theresult of the experiment indicates correctness of the design and feasibility ofSTATCOM. Reactive power is compensated well for three-phase symmetricalresistance-inductance load. In order to further validate the correctness and thefeasibility, hardware experiment of three-phase STATCOM is built under thecondition of low voltages such as the circuit of voltage zero detection, the circuit ofcurrent detection and so on. The results show that STATCOM can compensate thereactive power with symmetrical resistance-inductance load and prove the rationalityof design.