Capacitor Voltage Ripple Reduction in Modular Multilevel Converters in Drive Application

Given the increase in demand for medium voltage (MV) electric motors and their high-power capacity (ranging from hundreds of kilowatts to several megawatts), especially in power-intensive industries like oil, gas, and mining, there is a growing preference for multilevel converters. This is due to their ability to offer superior output quality, lower nominal voltage of semiconductor switches, reduced dv/dt, lower switching frequency, and minimized losses compared to the two-level voltage source converter (VSC). Specifically for high-power variable frequency drives in industrial settings, the Modular Multilevel Converter (MMC) has emerged as a highly promising topology within the multilevel converter family. The MMC boasts several advantages, including the absence of high voltage semiconductor switches, isolated DC sources, and complex transformers.