Modelling and airflow control of an oscillating water column for wave power generation

This paper deals with the modelling, simulation and control of a wave power plant installed in the northern cost of Spain. This plant is an onshore Oscillating Water Column (OWC) composed of a Wells turbine coupled to a Doubly Fed Induction Generator (DFIG). The power generated by the OWC is limited by the stalling behavior, a feature of the Wells turbine; therefore an airflow control is proposed in order to avoid the stalling phenomenon. This is achieved by regulating the airflow in the turbine duct by means of the throttle valve. The proposed control is based on a Proportional Integral (PI) controller. The results shows that the proposed control strategy provides a significant improvement of the generated power.