Study on SMES unit for improving the stability of power system connected with wind farms

The mathematic models for wind power generator and superconducting magnetic energy storage (SMES) unit are set up, and the function of SMES in improving the operation performance of wind farms is then studied. According to the short circuit fault in the grid and wind disturbance of the wind farms often occurred, a new strategy using the voltage deviation of the SMES connection point as control signal of the active power controller of SMES unit is presented. The simulation results show that with the designed controller, SMES can not only improve the transient stability of wind power system after short circuit of the grid, but also effectively smooth the output of wind farm and reduce the impulsion to power system during the fast wind disturbance.