TY - GEN
T1 - Decoupled Discontinuous Modulation for Cascaded H-Bridge StatCom with Star Configuration
AU - Liu, Qingxiang
AU - Rodriguez, Ezequiel
AU - Farivar, Glen G.
AU - Pou, Josep
AU - Townsend, Christopher D.
AU - Leyva, Ramon
N1 - Funding Information:
ACKNOWLEDGMENT This work was supported by the Office of Naval Research U.S. under DUNS Code: 595886219 and in part by the National Research Foundation of Singapore under “Distributed Energy Resource Management Systems (DERMS) For Energy Grid 2.0” project. The authors wish to acknowledge the Interdisciplinary Graduate Programme (IGP) at Nanyang Technological University for providing the conference funding support.
Publisher Copyright:
© 2022 IEEE.
PY - 2022
Y1 - 2022
N2 - This paper presents a novel zero-sequence voltage injection method for discontinuous modulation (DM) in star-connected cascaded H-bridge (CHB) static compensators (Stat-Coms). Conventional DM methods in CHB StatComs suffer from control interactions during unbalanced grid conditions. This paper proposes a DM that eliminates this control interaction by inserting a clamping transition within a third of the fundamental period. The transition instant is decided by comparing a duty cycle, which is calculated to mitigate the fundamental-frequency in the zero-sequence voltage for discontinuous operation, with a triangular carrier signal with a frequency of three times the fundamental. The clamping intervals under the proposed DM are affected by the phase-shift of this carrier. Specifically, the paper analyses the effects on the harmonic content of the proposed zero-sequence voltage, switching loss, twice-fundamental-frequency capacitor voltage ripple, and current total harmonic distortion, for different phase-shift angles of the DM carrier signal. Besides, the feasibility of the proposed DM in dealing with a grid voltage sag is also discussed.
AB - This paper presents a novel zero-sequence voltage injection method for discontinuous modulation (DM) in star-connected cascaded H-bridge (CHB) static compensators (Stat-Coms). Conventional DM methods in CHB StatComs suffer from control interactions during unbalanced grid conditions. This paper proposes a DM that eliminates this control interaction by inserting a clamping transition within a third of the fundamental period. The transition instant is decided by comparing a duty cycle, which is calculated to mitigate the fundamental-frequency in the zero-sequence voltage for discontinuous operation, with a triangular carrier signal with a frequency of three times the fundamental. The clamping intervals under the proposed DM are affected by the phase-shift of this carrier. Specifically, the paper analyses the effects on the harmonic content of the proposed zero-sequence voltage, switching loss, twice-fundamental-frequency capacitor voltage ripple, and current total harmonic distortion, for different phase-shift angles of the DM carrier signal. Besides, the feasibility of the proposed DM in dealing with a grid voltage sag is also discussed.
KW - Cascaded H-bridge (CHB)
KW - Discontinuous Modulation (DPWM)
KW - Static Compensator (STATCOM)
UR - http://www.scopus.com/inward/record.url?scp=85143891821&partnerID=8YFLogxK
U2 - 10.1109/IECON49645.2022.9969065
DO - 10.1109/IECON49645.2022.9969065
M3 - Conference paper
AN - SCOPUS:85143891821
T3 - IECON Proceedings (Industrial Electronics Conference)
BT - IECON 2022 - 48th Annual Conference of the IEEE Industrial Electronics Society
PB - IEEE, Institute of Electrical and Electronics Engineers
T2 - 48th Annual Conference of the IEEE Industrial Electronics Society, IECON 2022
Y2 - 17 October 2022 through 20 October 2022
ER -