Interarea oscillation damping using H-infinity control for the permanent magnet wind generator

This paper investigates the use of the permanent magnet wind generator as a means for damping dynamic interarea oscillations in multi-area power systems. A power modulation controller is proposed based on the H-infinity design methodology. The controller uses as feedback the frequency deviation of the local power system area and applies effective control on the wind generator rotor speed, blade pitch angle and dc link voltage in order to provide sufficient power modulation at the output of the generator to damp interarea oscillations. The paper also investigates the potential use of the energy stored in the dc link capacitance as an auxiliary means to increase the power modulation capability of the generator. The method is applied to a three-area power system that exhibits undamped rotor oscillations. Results presented in the paper demonstrate the effectiveness of the wind generator in increasing considerably the system damping.