A DC-DC modular multilevel topology for electrostatic renewable energy converters

This paper presents a novel Modular Multilevel DC-DC Converter (M2DC) topology capable of providing high voltage to electrostatic renewable energy converters. Electrostatic energy converters potentially offer high system reliability because they eliminate the need for a mechanical energy conversion interface, but high voltage in the range of 2.5-100 kV is required for their operation. The main feature of the M2DC topology is that it uses a secondary power loop to balance module capacitor voltages. The M2DC is compared with an existing solution for the same energy harvesting application showing advantages in isolation requirements and the number of switch gate drivers and magnetic components. Simulation results show that the M2DC topology is promising. Furthermore, utilization of the M2DC topology is not limited to electrostatic renewable energy converters, but also can, for example, be used in dc transmission systems.