Title :
MMC Capacitor Voltage Decoupling and Balancing Controls
Author :
Saad, Hani ; GUILLAUD, XAVIER ; Mahseredjian, Jean ; Dennetiere, Sebastien ; Nguefeu, Samuel
Author_Institution :
Ecole Polytech. de Montreal, Montreal, QC, Canada
Abstract :
A modular multilevel converter control system, based on converter energy storage, is proposed in this paper for two different control modes: active power and dc voltage. The proposed control system decouples the submodule (SM) capacitor voltages from the dc bus voltage. One of the practical applications is the management of active redundant SMs. A practical HVDC system with 401-level MMCs, including 10% redundancy in MMC SMs, is used for validating and demonstrating the advantages of the proposed control system. This paper also presents a novel capacitor voltage balancing control based on max-min functions. It is used to drastically reduce the number of switchings for each SM and enhances computational efficiency.
Keywords :
EMTP; HVDC power convertors; minimax techniques; voltage control; HVDC system; MMC capacitor voltage decoupling; SM capacitor voltages; capacitor voltage balancing control; converter energy storage; dc bus voltage; max-min functions; modular multilevel converter control system; submodule capacitor; Capacitors; Control systems; Converters; Equations; Mathematical model; Topology; Voltage control; Capacitor voltage balancing; Electromagnetic Transients Program (EMTP); HVDC; converter control; modular multilevel converter (MMC); redundant submodules; voltage–source converter (VSC);
Journal_Title :
Power Delivery, IEEE Transactions on
DOI :
10.1109/TPWRD.2014.2338861
