Simulation of multiple pulse width modulation (MPWM) transformerless photovoltaic inverter (TPVI) system

Abstract

Pulse width modulation technique is always applied in the design of inverter. The output voltage waveform of inverter is not relative pure sinusoidal, especially if it is applied linear pulse width modulation. A non-pure sinusoidal voltage waveform can affect the life time of inverter and also the alternating current (AC) loads. The inverter always also uses a transformer that can increase the losses and reduce the efficiency. A technique of multiple pulse width modulation (MPWM) is suitable to be applied in the transformerless photovoltaic inverter (TPVI) system. It can generate pure sinusoidal voltage waveform and increase the performance of inverter. This paper presents a simulation of MPWM TPVI system using SIMULINK MATLAB. It consists of pulse driver circuit to drive four MOSFETs in the full bridge inverter circuit with the output voltage waveform still multiple pulse wave and it is converted to be pure sinusoidal voltage waveform by applying a LC filter circuit.