Arm Modeling Approaches for Real-Time Simulation of Modular Multilevel Converter

Real-time simulation of modular multilevel converters (MMC) serves as a powerful tool for analyzing MMC, its control strategies, and behavior in various applications. However, the large number of power electronic switches in MMC presents a significant challenge for real-time simulation environments. To address the high computational burden associated with simulating a high number of switching devices, different types of modeling approaches are used. Therefore, this paper aims to explore various methods for modeling the arms of MMC that can still capture key dynamics, such as circulating currents and capacitor voltage fluctuations. The accuracy and performance of these modeling techniques are assessed by comparing the electrical quantities of each model with those of the full-switching model. Furthermore, the computational burden associated with each modeling approach is evaluated based on the number of submodules.