A Very High Efficiency Circuit Topology for a Few kW Inverter Based on Partial Power Conversion Principle

One trend of the fundamental enabling technologies into the direction of the eco-society with more electric power consumption is realization of ultra-high efficiency electric power conversion technologies. In this paper, a very high efficiency circuit topology for a few kW inverter is proposed based on a principle of partial power conversion. The new topology is made of (1) HEECS chopper for full rectified waveform generation and (2) unfolding full bridge inverter for full sinusoidal wave synthesis. The theoretical efficiency is derived, and the preliminary experimental verification confirmed the efficiency expectation. Tentatively, 99.2% efficiency was measured for the DC-to-full-rectified-waveform conversion at 3.6 kW output.