Modeling and simulation of seven level inverter based on multi-carrier control

In this paper, an analysis is given to the topology of cascaded seven-level inverter. Then its simulation model is set up. On the other hand, several carrier control strategies are discussed, modeled and applied for the control of this multilevel inverter respectively, including phase disposition, phase opposition disposition and alternative phase opposition disposition. Then the switching control signals are properly produced according to the working principle of this inverter respectively. Finally, the simulation models of the total system are set up respectively and the demanded experiments are carried out. The results have verified the feasibility and easy realization of multi-carrier control strategies for this multi-level inverter. Further, these several multi-carrier control strategies are analyzed and compared in detail. Then some useful conclusions are obtained according to simulation waveforms and corresponding spectrum analyses. They lay good foundations for future researches.