Study on the stability of large wind power grid-connected system including different types of wind generators

Reactive power characteristics and control of wind generator greatly impact the stability of power grid connected with wind farm. For the wind power grid-connected system including different types of wind generators, this paper proposed a management strategy of reactive power coordination based on analyzing reactive power voltage characteristics of variable-speed constant-frequency double-fed wind turbine (DFIG). The strategy could make full use of reactive power regulation function of DFIG to compensate reactive consumption of nearby constant speed constant frequency asynchronous induction wind generator (FSIG). Simulations with IEEE_9 node standard benchmark system are studied. The results show that because the maximum reactive power output capacity of DFIG increases with stator voltage decreasing, the reactive power control strategy real-timely and effectively plays its reactive regulation capability, thus improves static voltage stability margin of the wind power system and make multi-machine system maintain better transient voltage and angle stability while large disturbance occurs.