Super Capacitor Energy Storage Based MMC for Energy Harvesting in Mine Hoist Application

This paper proposes a super capacitor energy storage-based modular multilevel converter (SCES-MMC) for mine hoist application. Different from the conventional MMCs, the sub-modules employ distributed super capacitor banks, which are designed to absorb the regenerative energy of mine hoist and released in the traction condition, so as to improve energy utilization efficiency. The key control technologies are introduced in detail, followed by analysis of the configuration and operation principles. The feasibility of the proposed SCES-MMC topology and the control theory are also verified. Simulation results show that SCES-MMC can adapt to the variable frequency speed regulation of the motor drive, which shows good application prospects in the future for medium- and high-voltage mine hoist systems.