This paper investigates the performance of three-phase grid connected multi-level (PWM) inverter, with photovoltaic energy conversion system being the main application. The main purpose of this work is to reduce the common mode voltage (CMV) and common mode current (CMC), the performance of the inverter is studied thoroughly. Conventional PWM methods and recently developed reduced common mode voltage PWM (RCMV-PWM) methods are reviewed. The simulation results of CMV, CMC and Total Harmonic Distortion (THD) by applying all the PWM Techniques on a grid-connected PV system using a three-phase, three-level Multi-Level Inverter (MLI) are studied. Amongst all the PWM Techniques, Near State PWM (NSPWM) Technique which is an RCMV-PWM Technique yields the best results.