Characteristic investigation and control of a modular multilevel converter-based HVDC system under single-line-to-ground fault conditions

Journal Article · Fri May 16 00:00:00 EDT 2014 · IEEE Transactions on Power Electronics

DOI:https://doi.org/10.1109/TPEL.2014.2323360· OSTI ID:1326497

Shi, Xiaojie ^[1]; Wang, Zhiqiang ^[1]; Liu, Bo ^[1]; Liu, Yiqi ^[2]; Tolbert, Leon M. ^[3]; Wang, Fred ^[3]

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1. The Univ. of Tennessee, Knoxville, TN (United States)
2. Harbin Institute of Technology, Harbin (China)
3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

This paper presents the analysis and control of a multilevel modular converter (MMC)-based HVDC transmission system under three possible single-line-to-ground fault conditions, with special focus on the investigation of their different fault characteristics. Considering positive-, negative-, and zero-sequence components in both arm voltages and currents, the generalized instantaneous power of a phase unit is derived theoretically according to the equivalent circuit model of the MMC under unbalanced conditions. Based on this model, a novel double-line frequency dc-voltage ripple suppression control is proposed. This controller, together with the negative-and zero-sequence current control, could enhance the overall fault-tolerant capability of the HVDC system without additional cost. To further improve the fault-tolerant capability, the operation performance of the HVDC system with and without single-phase switching is discussed and compared in detail. Lastly, simulation results from a three-phase MMC-HVDC system generated with MATLAB/Simulink are provided to support the theoretical analysis and proposed control schemes.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1326497
• Journal Information: IEEE Transactions on Power Electronics, Vol. 30, Issue 1; ISSN 0885-8993
• Publisher: IEEE
• Country of Publication: United States
• Language: English

Related Subjects

24 POWER TRANSMISSION AND DISTRIBUTION
high-voltage direct-current (HVDC)
modular multilevel converter (MMC)
single-line-to-ground (SLG) fault
voltage control
HVDC transmission
current control
circuit faults
frequency control
reactive power
converters