Integration of a Wind-Wave Hybrid Energy System with the Distribution Network

This paper introduces the hybridization of multiple permanent magnet linear generator (PMLG)-based wave energy conversion systems with a doubly-fed induction generator (DFIG) based wind energy conversion system. A detailed investigation of the impact of the integration of the wind-wave hybrid system with the distribution network is presented. The control scheme for the multiple PMLGs ensures the optimum extraction of the wave power and the ability to maintain voltage balance at the outputs of the PMLGs. Similarly, the back-to-back converters of the DFIG are controlled for the maximum power point tracking of the wind turbine and for the dc-link voltage regulation. The turbine rotor blade pitch angle is controlled to minimize the power fluctuations caused by the integration of PMLGs at the common DC bus. The time-domain simulation results confirm the effectiveness of the proposed system by showing a stable operation when integrated with the distribution test feeder. Finally, the steady-state analysis shows that the voltage profile of the distribution network is also improved, and the step voltage regulator of the distribution feeder can be removed in the presence of the proposed system without violating the voltage limits at any node of the selected distribution network.