Title :
A flexible DC voltage balancing control based on the power flow management for star-connected cascaded H-bridge converter
Author :
Chia-Tse Lee ; Hsin-chih Chen ; Ching-wei Wang ; Ping-Heng Wu ; Ching-hsiang Yang ; Po-Tai Cheng
Author_Institution :
Dept. of Electr. Eng., Nat. Tsing Hua Univ., Hsinchu, Taiwan
Abstract :
This paper presents the flexible dc capacitor voltages balancing control method for star-connected cascaded H-bridge converters. In this paper, the power flows are analysed by investigating all the converter´s control freedoms. Based on the analyses, users can accomplish dc capacitor voltage balancing with both negative-sequence current and zero-sequence voltage. These two kinds of control options are further integrated together with the defined weighting factor μ. The low-voltage ride-through operation of proposed control method is also discussed in this paper. The control method is verified with a 220-V 1kVA STATCOM based on star-connected cascaded H-bridge converters, and the experimental test results show that all the dc voltages are well-regulated at the commanded value with different weighting factor μ.
Keywords :
electric current control; load flow control; power capacitors; power convertors; power system management; static VAr compensators; voltage control; STATCOM; apparent power 1 kVA; flexible DC capacitor voltage balancing control method; low-voltage ride-through operation; negative-sequence current control; power flow management; star-connected cascaded H-bridge converter; voltage 220 V; weighting factor K; zero-sequence voltage control; Automatic voltage control; Capacitors; Equations; Mathematical model; Power system stability; Reactive power; Capacitor voltage balancing control; Low-voltage ride-through (LVRT); Modular Multilevel Cascaded Converter; PWM cascaded converter; STATCOM;
Conference_Titel :
Energy Conversion Congress and Exposition (ECCE), 2014 IEEE
Conference_Location :
Pittsburgh, PA
DOI :
10.1109/ECCE.2014.6953934
