EMI Reduction in Transformerless Photovoltaic Grid-Connected Inverter via Chaotic SPWM Control

This paper proposes a chaotic unipolar sinus pulse width modulation (CUSPWM) algorithm for transformerless grid-tied single-phase photovoltaic (PV) inverter. The aim of the study is to reduce electromagnetic interferences (EMI) emitted by a PV inverter. First, a detailed description of theoretical developments is presented. Thereafter, the proposed CUSPWM is implemented and validated on a H5 PV inverter topology using a circuit type software. Moreover, a comparative study between the conventional unipolar SPWM and CUSPWM algorithms is carried out. According to the obtained results, the CUSPWM is advantageous over the standard SPWM control because it provides a significant reduction in the amplitude of both common-mode (CM) current and the CM voltage over a wide frequency band.