Generalized cascaded Multi Level Inverter using reduced number of components with PV systems

Abstract

A Multi Level Inverter (MLI) has numerous industrial applications over a conventional two-level inverter due to its attractive features like it produces staircase output waveform with very lower distortion, it has less dv/dt stresses on switches, it operates effectively in both symmetric and asymmetric states, it performs at lower switching frequency and hence lower switching loss, etc. But, unfortunately, it needs greater number of power semiconductor switches and associated gate drive circuits. So, it may cause the overall system to be more complex and expensive. This paper presents a new topology of MLI with reduced number of semi conductor switches typically called as generalized cascaded MLI (with constant DC voltage sources). It can be analysed in both symmetric and asymmetric states by considering different criteria for optimal structures such as minimum number of DC sources, gate driver circuits, power electronic switches, minimum standing voltage on switches etc. In this work, DC source is realized using Photo Voltaic (PV) systems. The most well-known Perturb and Observe (P&O) algorithm is used for PV systems to achieve Maximum Power Point (MPP). The efficacy of aforementioned method is verified through Total Harmonic Distortion by taking R and RL loads. The simulation has been accomplished in MATLAB.