Loss Minimization Control for Doubly-Fed Induction Generators in Variable Speed Wind Turbines

In this paper, a novel control algorithm for minimizing the operating loss of doubly fed induction generators (DFIG) for variable speed wind turbines is presented. At first, the generator losses are modeled, which consist of the copper loss and the iron losses. Then, a stator d-axis current is derived which minimizes the total generator loss. Based on this current, the stator reactive power level is controlled. The experimental results for a 3 kW DFIG wind turbine simulator show that the amount of power saving approaches to 23% at 5[m/s] wind speed, which is more significant at low wind speed.