Independent-phase current control of a three-phase VSC under unbalanced operating conditions

The Journal of Engineering

  ^{1    1} 

[1] Department of Electrical and Computer Engineering, University of Manitoba, Winnipeg, MB, Canada;

关键词: phase locked loops;    power convertors;    voltage control;    electric current control;    power control;    unbalanced operating conditions;    independent phase-current-control architecture;    three-phase voltage source converter;    PLLs;    dual-loop scheme;    ac voltage control;    second-order generalised integrator-based PLL;    phase-tracking angle;    active power control;    inner current control loops;    three-phase VSC;    single-phase phase locked loops;    imbalance-induced distortions;    half-bridge modular multilevel converter;    PSCAD/EMTDC;    power 500 MW;    voltage 500 kV;   

DOI  :  10.1049/joe.2018.8768

来源: publisher

【 摘 要 】

This study presents an independent phase-current-control architecture for a three-phase voltage source converter. It comprises three independent single-phase phase locked loops (PLLs), and a dual-loop scheme including an outer loop (responsible for active power and ac voltage control) and three similar inner current control loops. To obtain reliable phase-tracking, an enhanced second-order generalised integrator-based PLL is developed. The phase-tracking angle is strategically selected from the three PLLs to minimise the impact of imbalance-induced distortions. To validate the proposed control scheme, extensive simulations are conducted for a 101-level, 500-MW, 500-kV (dc) half-bridge modular multi-level converter in PSCAD/EMTDC. The simulation results prove that the proposed scheme enables the system to ride through unbalanced conditions effectively and reliably.

【 授权许可】

CC BY