A Currentless Sorting and Selection-Based Capacitor-Voltage-Balancing Method for Modular Multilevel Converters

Capacitor Voltage Monitoring in Modular Multilevel Converter

A Modular Multilevel Converter (MMC) is an attractive solution for power conversion without transformers. As MMC consists of cascade connections and floating dc capacitors, it requires continuous voltage monitoring. An adaptive observer design has been presented to estimate the capacitor voltages from the measurement of arm currents. This work introduces a capacitance value of the cell capacito...

Analysis of Modulation and Voltage Balancing Strategies for Modular Multilevel Converters

Trade-Off Strategies in Designing Capacitor Voltage Balancing Schemes for Modular Multilevel Converter HVDC

This paper focuses on the engineering trade-offs in designing capacitor voltage balancing schemes for modular multilevel converters (MMC) HVDC: regulation performance and switching loss. MMC is driven by the on/off switch operation of numerous submodules and the key design concern is balancing submodule capacitor voltages minimizing switching transition among submodules because it represents th...

Investigation of Capacitor Voltage Regulation in Modular Multilevel Converters with Staircase Modulation

This paper presents a detailed theoretical analysis and performance assessment of the capacitor voltage balancing strategies for staircase modulated modular multilevel converters (MMC) in terms of the algorithm structures, voltage balancing effect, and switching frequency. A constant-frequency redundancy selection (CFRS) method with minimal switching loss is proposed and the function realizatio...

Submodule Temperature Regulation and Balancing in Modular Multilevel Converters

In modular multilevel converters (MMCs), tem5 perature control of semiconductor devices in the submod6 ules (SMs) is a key factor for the safe and reliable opera7 tion. Under normal operation, significant temperature differ8 ences can exist between SMs due to, for example, aging of 9 semiconductor modules and module parameter mismatch. 10 This paper presents a method for achieving SM thermal ba...