Phase Shifted PWM Cascaded Multilevel Inverter for Solar PV Grid Integration

Power conversion using multilevel convertes became very popular in past few years. They have the advantages of quality power output, high voltage compatibility, low electromagnetic compatibility concerns. The structure of these multilevel inverters permits them to reach high voltages with a low value of total harmonic distortion, without using transformers or any other harmonic reduction techniques like series connected synchronized switching devices. The general function of these inverters is to synthesize a staircase AC output voltage from several DC voltage levels. With an increment in number of levels the staircase waveform nears a more sinusoidal form which approaches tm which is the desired output of the inverter. With an increase in the number of steps in the waveform, its total harmonic distortion decreases and may approach to zero for some higher levels. In this paper seven level three phase cascaded multilevel inverter is simulated with phase shifted pulse width modulation. The topology is being proposed for grid integration of solar PV.