Direct Drive Ocean Wave Energy Converter Based Off-grid supply System

This paper proposes a two-stage methodology to utilize the power generated by direct drive Permanent Magnet Linear Generator (PMLG) based Ocean Wave Energy Converters (OWECs) at a discontinuous wave pattern. The discontinuous ocean wave pattern for PMLG generates discontinuous variable A.C. voltage. The generated discontinuous variable A.C. should be converted into continuous constant A.C. before supply to the A.C. load end. For this purpose, the discontinuous variable A.C. voltage is converted into a discontinuous variable D.C. voltage by a standard rectifier. Thereafter, the variable D.C. voltage is utilized to charge the battery bank through the battery charging circuit; after that, a low THD buck-boost inverter is connected to supply a higher sinusoidal A.C. voltage at the load end. Systematic designs of power converters along with the PWM control strategy are also discussed. The simulation results and results from a laboratory prototype are presented to support the theoretical concepts.