Three-Phase Multilevel Inverter With Reduced Number of Power Electronic Components

Abstract

In this paper, a new configuration of a three-phase five-level multilevel voltage-source inverter is introduced. The proposed topology constitutes the conventional three-phase two-level bridge with three bidirectional switches. Multilevel inverters are mainly used in medium voltage and high power  applications to reduce the required voltage rating of the power semiconductor switching devices. On the other hands, these multilevel inverters are attractive for various applications regardless of the power ratings because they can essentially realize lower harmonics with lower switching frequency and lower electromagnetic interference (EMI). In this context, the multilevel inverters with larger number of levels suitable for circuit integration are actively investigated. A multilevel dc link usin fixed dc voltage supply and cascaded half-bridge is connected I such a way that the proposed inverter outputs the required output voltage levels. The fundamental frequency staircase modulation technique is easily used to generate the appropriate switching gat signals. For the purpose of increasing the number of voltage level with fewer number of power electronic components, the structure of the proposed inverter is extended and different methods to determine the magnitudes of utilized dc voltage supplies are suggested Moreover, the prototype of the suggested configuration is manufactured as the obtained simulation and hardware results ensure the feasibility of the configuration and the compatibility of the modulation technique is accurately noted.