THE NTV-SV-PWM METHOD USING AN IMPROVED LOOK-UP TABLE FOR DC-LINK MID-POINT BALANCING APPLIED FOR OCEAN WAVE ENERGY CONVERSION SYSTEM

Abstract

The research activities for maximum energy absorption from wave energy converters (WECs) are very often limited to hydrodynamic control and performance of the power take-off (PTO) which mostly simplifies the power electronics conversion systems. There are only few studies that show deep analysis of connecting the generated voltage to the grid by using the most developed power electronics technologies. The main objective of this study is (i) to develop a full wave-to-grid model to show all conversion stages from ocean waves to the electricity network, (ii) to combine the WEC with neutral point clamped (NPC) inverter which uses advanced nearest three vector–space vector–pulse width modulation (NTV-SV-PWM) method based on a look-up table that can build up a sinusoidal voltage waveform at the inverter output with the least number of switching in the power circuit and the best possible harmonic spectrum without the need for any big filtering.