Medium-Voltage Power Converter Interface for Multigenerator Marine Energy Conversion Systems

Marine energy conversion systems are highlighted among nonconventional renewable energy sources for their availability and energy density. Most marine energy conversion systems are based on multigenerator units or arrays, projected to inject power to the grid in the megawatt range. The current solution for regulating generators and managing power output is the use of two-level voltage-source converters in a back-to-back configuration for each generator. This work presents the model, control scheme, and experimental validation of a configuration, which is able to interface medium-voltage high-power multigenerator marine energy conversion systems to the grid at medium-voltage high-power levels. The configuration is based on a two-step rectifier/boost converter for each generator and a multilevel inverter that merges and manages the multiple power outputs from the multigenerator section of the system. The multilevel inverter is responsible for controlling power flow to the grid and provides regulated medium-voltage high-power injection.