A Non-Resonant Linear Soft-Switching Two-Stage Inverter and Its Integrated Control

Miniaturization and lightweight are the development trends of photovoltaic (PV) inverters. Therefore, soft switching technology is very important for improving the efficiency of the inverters with high switching frequency. Traditional resonant soft-switching techniques bring high current or voltage stress of switches in PV inverter due to the resonance peaks. In this paper, a non-resonant linear soft-switching (NRLSS) technique is proposed for a two-stage PV inverter, as well as a new two-stage integrated control is applied to realize the NRLSS technique in the inverter. In detail, the topology of the proposed two-stage PV inverter is firstly introduced. Further, the integrated control is applied and its advantage on reducing the power losses are stated. Following, the operating principle of the two-stage inverter is introduced and the effectiveness of the NRLSS technique is finally proved by simulation and experiment. This paper provides a new topology for the PV inverters with the requirements of high switching frequency and high efficiency.