Design and Comparison of Cascaded H-bridge, 5-L Active Neutral Clamped and Modular Multilevel Converter Topologies for Medium-Voltage Drive Application
This paper investigates the design procedure of cascaded H-bridge (CHB), 5-L active neutral point clamped (ANPC) and modular multilevel converter (MMC) topologies for medium-voltage and high-power industrial motor drive applications. The design is carried out using 1.7-kV insu-lated gate bipolar transistor (IGBT) technology for MMC and CHB topologies, and using 3.3-kV and 4.5-kV IGBTs for a 5-L ANPC converter. A model is derived for a multi-pulse transformer to take into account its leakage parameters' effect on converter design. A comparison is also made between topologies at different voltage and power levels. For MMC and CHB, the three following voltage levels are chosen: 4.16-, 6.9- and 13.8-kV. The 5-L ANPC is designed only at the two lower levels of the aforementioned voltages. Converters are designed at the following three different power levels: 1-, 3- and 5-MVA. A comparison is done from several points of view, such as capacitance requirements, diode front-end and inverter stage losses, semiconductor rating and junction temperature, and parts count.