Control of losses in double fed induction generators used in WECS

In this paper, the steady state performance of the doubly-excited induction generator (DEIG) used in wind energy conversion systems (WECS) is investigated. The stator, rotor and core losses are calculated at a speed ranging from sub-to-super-synchronous speeds. The rotor applied voltage magnitude and phase angle at which losses are minimal at each speed are deduced. It is shown that core losses constitute a considerable amount to the total losses and hence ought not to be neglected for the sake of accuracy. The efficiency and power factor of the DEIG at each speed are also calculated.