| In recent years, multilevel power conversion technology has been becoming hot point in power electronic research due to extensive outlook in high power application. Novel topologies and modulation strategies concerning multilevel converters are emerging continuously.Several independent H-bridge as the basic power unit constitute a cascade multi-level cascade inverter. In spite of multi-level cascade inverter has many advantages, such as low harmonic pollution, high input power factor and perfect output waves. However each single-Phase inverter requires its own isolated DC power supply. So inverter require more independent DC power supply and power transformation devices when inverter have a few more output voltage level. In order to solve this questions, a capacitor hybrid cascaded multi-level is proposed.1. In this thesis, the several main topologies of multilevel inverter have been compared; their respective advantages and disadvantages were analyzed carefully.2. The mathematical mode of cascaded multilevel inverter and capacitor hybrid cascaded multilevel inverter are estiblished. Compare to the traditional cascade topology, capacitor hybrid cascade multilevel require less independent DC power supply, and simplifying the structure of the main circuit.3. Carrier phase reverse control method is proposed. After using the storage capacitor to replace DC power supply, ideal output voltage of the five-level structure is produced. The simulation results show that the output wave have the same frequency with modulation wave.4. The main circuit and the control circuit of capacitor hybrid cascaded multilevel inverter are designed. After using the Multisim 2001 for the simulation experiment, it show that the storage capacitor voltage similar to DC power supply.
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