Research on MMC Voltage Equalization Control Strategy Based on Optimal Sorting Algorithm

Abstract

The voltage sharing control strategy based on sorting algorithm is widely used in modular multilevel converter Converter (MMC) in practical engineering, aiming at the problems of frequent switching states, high switching frequency and large loss caused by traditional scheduling algorithm, a voltage sharing control strategy based on optimal sequencing is proposed by introducing the average value of capacitor voltage and the maximum deviation threshold under the premise of considering the switching state of sub modules at the last moment. Finally, the simulation system of modular multilevel converter is built in PSCAD / EMTDC for verification. The simulation results show that the proposed optimal sequence voltage sharing control strategy significantly reduces the switching frequency of the devices and improves the operation performance of the system.