가변속 풍력발전기의 속도특성

Wind power generating system is classified into constant speed and variable speed system. The former is mainly composed of squirrel cage induction machine and the later is composed of synchronous generator or wound rotor induction generator. The variable speed system is more adequate to maximize the energy capture from wind energy, whereby the turbine speed can be adjusted to a speed, at which a tip speed ratio be kept within its rated value so that the maximum power coefficient of the turbine can be reached. In this paper, speed characteristics of adjustable speed wind power generator is dealt and for realization of it, wound rotor induction generator, so called doubly-fed induction generator (DFIG), is chosen for bench work test and his speed characteristics, in range of super- and sub-synchronous speed, are measured.