The conventional PWM inverters are able to generate mostly two level output waveforms. Many improvements have been proposed to classic configuration as regards the circuit structures, the control schemes, but the inverter performance was limited by the available number of levels to build the output voltage. To overcome these difficulties several topologies of multilevel inverter have been recen...

This paper intmduces the circuit and PWM control strategies of the Neutral-Point-Clamped (NPC) inverter and Cascade-Inverters with Separate DC Source (CISDS), analyzes and compares their advantages and disadvantages. A new type of Parallel Connected NPC inverter (PCNPCI) is proposed here. Based on inherited all merits of the three-level structures, only added very few components, it can produce...

Multilevel inverters (MLI) becomes more accepted over the last few years in high power application of electrical engineering with the advantage of less disturbances and the possibility to work at lower switching frequencies as compared to conventional two-level inverters. In this paper the simulation of single phase multilevel inverter is present. Simulation of three level, five level, seven le...

The paper presents a short overview of the state of the art for grid tied PV inverters at low and medium power level (1..100 kW), mainly intended for rooftop applications. The inverters are categorized according to the configuration of the PV system, the configuration of the conversion stages within the inverter and whether they use transformers or not [1], [3]. After the introduction of the st...

Power electronic converters are becoming more and more popular for various industrial applications. To overcome the limitation of semiconductors current and voltage ratings in high power applications, series and parallel connection of switches is often considered an effective solution. In addition, stepped waveform in the output of inverter has better harmonic spectrum than 2-level waveform in ...

Transormerless inverters are attractive solution for the grid connected photovoltaic (PV) systems. Unfortunately, it has issues on galvanic isolation between PV systems to the grid. When the galvanic isolation disappears from the PV inverter, leakage currents will flow in a resonant circuit formed by the ground capacitance, the converter, the ac filter and the grid. In order to avoid the leakag...