Power quality enhancement of grid-connected wind power generation system by SMES

Dispersed power generation systems are expected as important electric power supply systems for the next generation. Wind power generation system (WPGS) is widely being introduced in the worldwide power utilities. The WPGS output power fluctuates due to wind speed variations. Hence, if a large number of wind power generators are connected to the grid system, their output can cause serious power quality problems, that is, frequency and voltage fluctuations may happen. In order to solve these problems, the smoothing control of wind power generator output is very important. In addition, Superconducting Magnet Energy Storage (SMES) is surely one of the key technologies to overcome these fluctuations. The SMES can compensate even small disturbances. With these points as background, this paper deals with power quality enhancement of grid-connected WPGS by pitch control and SMES. EMTDC and RTDS based simulations are performed for a small island power system including WPGS and the results are discussed in detail.