ABSTRACT Non‐isolated multilevel inverters with common ground structure are very beneficial in photovoltaic (PV) grid connection applications. These inverters eliminate the crucial common mode leakage current in the photovoltaic grid connection system by directly connecting the negative pole of the photovoltaic cell to the neutral point of the grid. In this paper, a novel inverter structure of this type is proposed. The proposed inverter has the following features: (1) With a common ground structure, theoretically, leakage current can be completely eliminated, which is beneficial for improving the reliability of the system. (2) Capability to meet the peak amplitude requirement of the grid voltage under wide input voltage variations. (3) The output voltage of the bridge arm is a five‐level waveform, which is beneficial for improving the output power quality and reducing the volume of the filter. (4) The proposed topology uses a small number of devices, which can not only achieve continuous input current, but also have boost function. This paper analyzes in detail the working principle, model predictive control (MPC) strategy, and power loss of the proposed inverter. Experimental results verify the feasibility of the theoretical analysis and the excellent performance of the proposed topology structure.
Hu et al. (Sat,) studied this question.