Research on the switching transients and disconnecting transients of shunt capacitors in grid-connected wind farms

This paper analyzes the causes for abnormal phenomena when switching and disconnecting shunt capacitors theoretically, also establishes an overall dynamic model for wind turbine set, including the wind-turbine and asynchronous induction generator. It constructs a model of wind farm that is connected with infinite system on the basis of dynamic model above. The numerical simulations are performed to evaluate switching and disconnecting transients of shunt capacitors during ramp wind speed. The paper focus on inrush currents and low transition voltage during switching as well as over-voltages during disconnecting caused by single phase or double phases connect again. The approaches to solve these problems are presented. The simulation conclusions are proved by the experimental test.