Modelling of grid tied 3-level diode clamped inverter using space vector PWM for PV system

In this work the AC Load is fed from solar radiation energy by means of Three-level Diode-Clamped Inverter. The entire system is implemented with three phase supply system. For making the system more efficient, Maximum Power Point Tracking (MPPT) device is used. The Perturb & Observe technique is adopted to obtain voltage at maximum power. In this paper, Space Vector Pulse Width Modulation (SVPWM) technique is used to generate gate pulses to make inverter switches ON and OFF periodically. IGBTs are used as a switching device. With the help of latest new vectors, the new gate pulses are generated and the system is interfaced with Grid. Without a filter, the %THD of line voltage is 32.24% and with the incorporation of filter in the system the %THD of line voltage drastically reduces to 4.91%. The modelling of the entire system is performed through MATLAB/Simulink in this work The paper also presents the comparison of the results of line voltages for the proposed system with Sinusoidal Pulse Width Modulation (SPWM) and SVPWM techniques.