TY - JOUR
T1 - An Overview of Modular Multilevel Converters in HVDC Transmission Systems With STATCOM Operation During Pole-to-Pole DC Short Circuits
AU - Nguyen, Thanh Hai
AU - Hosani, Khalifa Al
AU - S. El Moursi, Mohamed
AU - Blaabjerg, Frede
PY - 2019/5
Y1 - 2019/5
N2 - Fault-current handling capability of the modular multilevel converters (MMCs) under dc-cable short-circuit conditions is a major concern for the MMC applications on the high-voltage direct-current (HVDC) transmission systems, where the MMCs based on half-bridge submodules (SMs) cannot block the fault currents to protect the converter devices. In this paper, a comprehensive review for the fault-ride-through capability of the HVDC transmission systems based on the MMCs adopting different SM schemes is presented, where the MMCs can block the fault currents and compensate the reactive currents to the electric grid during the dc faults. An analysis of the dc short-circuit faults in the MMC is introduced and then the operation principle of different SM circuits building the MMC for blocking the fault currents is highlighted. The fault-tolerant operation of these MMC schemes as static synchronous compensator to enhance the ac grid stability during the dc faults is also investigated. A comparison in terms of investment cost, loss, volume, and controllability for various MMC topologies is performed. Comprehensive simulation results for the most promising topologies of the MMC with a capability of fault-ride through under dc-fault conditions are finally presented.
AB - Fault-current handling capability of the modular multilevel converters (MMCs) under dc-cable short-circuit conditions is a major concern for the MMC applications on the high-voltage direct-current (HVDC) transmission systems, where the MMCs based on half-bridge submodules (SMs) cannot block the fault currents to protect the converter devices. In this paper, a comprehensive review for the fault-ride-through capability of the HVDC transmission systems based on the MMCs adopting different SM schemes is presented, where the MMCs can block the fault currents and compensate the reactive currents to the electric grid during the dc faults. An analysis of the dc short-circuit faults in the MMC is introduced and then the operation principle of different SM circuits building the MMC for blocking the fault currents is highlighted. The fault-tolerant operation of these MMC schemes as static synchronous compensator to enhance the ac grid stability during the dc faults is also investigated. A comparison in terms of investment cost, loss, volume, and controllability for various MMC topologies is performed. Comprehensive simulation results for the most promising topologies of the MMC with a capability of fault-ride through under dc-fault conditions are finally presented.
KW - DC short-circuit faults
KW - Fault-handling capability
KW - High-voltage direct-current (HVDC) transmission systems
KW - Modular-multilevel converters
KW - Static synchronous compensator (STATCOM)
KW - Submodules (SMs)
UR - http://www.scopus.com/inward/record.url?scp=85050984863&partnerID=8YFLogxK
U2 - 10.1109/TPEL.2018.2862247
DO - 10.1109/TPEL.2018.2862247
M3 - Journal article
SN - 0885-8993
VL - 34
SP - 4137
EP - 4160
JO - I E E E Transactions on Power Electronics
JF - I E E E Transactions on Power Electronics
IS - 5
M1 - 8424079
ER -