IEEE Transactions on Energy Conversion, Vol.23, No.2, 632-641, 2008
Voltage and frequency control of a stand alone brushless wind electric generation using generalized impedance controller
In this paper, a new strategy for the control of terminal voltage and frequency of a stand-alone self-excited induction generator-(SEIG) based wind generator, working with variable speed and load is proposed. With a generalized impedance controller (GIC) (voltage source pulsewidth-modulated inverter with a dc-link battery), a new strategy to maintain the active and reactive power balance at the SEIG terminals has been introduced to control its terminal voltage and frequency. In the proposed con trol strategy, only a voltage feedback loop has been used to control both the SEIG terminal voltage and the frequency. A mathematical model of the SEIG-GIC system under wind generator environment has been developed and simulated in the MATLAB/Simulink. The simulation results are validated with the experimental ones conducted on a laboratory prototype of the SEIG-GIC system. The novelty of the present technique is that the GIC is capable of maintaining a constant SEIG terminal voltage and frequency, following both speed and load perturbations, with only a single (voltage) feedback loop.
Keywords:active and reactive power controller;frequency controller;generalized impedance controller (GIC);self-excited induction generator (SEIG);voltage controller