PUBLICATIONS

This paper presents an implementation of a direct active and reactive power control for a doubly fed induction generator (DFIG),

which is applied to a wind generation system as an alternative to the classical field-oriented control (FOC). The FOC has a complex

control structure that consists of a current controller, a power controller and frame transformations. The performance of the FOC

depends highly on parameter variations of the rotor and stator resistances and the inductances. The proposed direct power control

(DPC) method produces a fast and robust power response without the need of complex structure and algorithms. One drawback,

however, is its high power ripple during a steady state. In this paper, active and reactive power controllers and space-vector

modulation (SVM) are combined to replace hysteresis controllers used in the original DPC drive, resulting in a fixed switching

frequency of the power converter. Simulation results with the FOC and DPC for a 3kW DFIG are given and discussed, and the

experimental results of a test involving identical machines are presented to illustrate the feasibility of the proposed control strategy