Protection of Nonpermanent Faults on DC Overhead Lines in MMC-Based HVDC Systems

A high-voltage direct current system using modular multilevel converter (MMC-HVDC) is a potential candidate for grid integration of renewable energy over long distances. The dc-link fault is an issue MMC-HVDC must deal with, especially for the nonpermanent faults when using overhead lines. This paper proposed a protection scheme to implement fast fault clearance and automatic recovery for nonpermanent faults on dc lines. By employing double thyristor switches, the freewheeling effect of diodes is eliminated and the dc-link fault current is allowed to freely decay to zero. Then, the dc arc can be naturally extinguished and the insulation on the short-circuit point can be restored. The thyristor switches convert the dc-link fault into an ac short circuit of the ac grid through MMC arms. The ac short-circuit current can be cleared simply by turning off all thyristor switches. Since circuit breakers are not tripped during fault clearance, MMC can immediately and automatically rebuild the dc-link voltage and restart power transmission. Simulation results using PSCAD/EMTDC have verified the validity of the proposed protection scheme.

[1]  V.G. Agelidis,et al.  VSC-Based HVDC Power Transmission Systems: An Overview , 2009, IEEE Transactions on Power Electronics.

[2]  Reza Iravani,et al.  Dynamic performance of a modular multilevel back-to-back HVDC system , 2010, 2011 IEEE Power and Energy Society General Meeting.

[3]  Boon-Teck Ooi,et al.  Locating and Isolating DC Faults in Multi-Terminal DC Systems , 2007, IEEE Transactions on Power Delivery.

[4]  Rainer Marquardt,et al.  An innovative modular multilevel converter topology suitable for a wide power range , 2003, 2003 IEEE Bologna Power Tech Conference Proceedings,.

[5]  Marc Hiller,et al.  Modulation, Losses, and Semiconductor Requirements of Modular Multilevel Converters , 2010, IEEE Transactions on Industrial Electronics.

[6]  Rainer Marquardt,et al.  Modular Multilevel Converter topologies with DC-Short circuit current limitation , 2011, 8th International Conference on Power Electronics - ECCE Asia.

[7]  Nouredine Hadjsaid,et al.  High Voltage Direct Current (HVDC) Transmission , 2013 .

[8]  Guangfu Tang,et al.  Characteristics and Recovery Performance of VSC-HVDC DC Transmission Line Fault , 2010, 2010 Asia-Pacific Power and Energy Engineering Conference.

[9]  H. Akagi,et al.  Control and Experiment of Pulsewidth-Modulated Modular Multilevel Converters , 2009, IEEE Transactions on Power Electronics.

[10]  Hirofumi Akagi.  Classification, Terminology, and Application of the Modular Multilevel Cascade Converter (MMCC) , 2011 .

[11]  Kurt Friedrich,et al.  Modern HVDC PLUS application of VSC in Modular Multilevel Converter topology , 2010, 2010 IEEE International Symposium on Industrial Electronics.

[12]  Tomas Modeer,et al.  Loss comparison of different sub-module implementations for modular multilevel converters in HVDC applications , 2011, Proceedings of the 2011 14th European Conference on Power Electronics and Applications.

[13]  T. C. Green,et al.  Control of a modular multilevel converter-based HVDC transmission system , 2011, Proceedings of the 2011 14th European Conference on Power Electronics and Applications.

[14]  Staffan Norrga,et al.  HVDC SuperGrids with modular multilevel converters — The power transmission backbone of the future , 2012, International Multi-Conference on Systems, Sygnals & Devices.

[15]  W.L. Kling,et al.  HVDC Connection of Offshore Wind Farms to the Transmission System , 2007, IEEE Transactions on Energy Conversion.

[16]  Xu Dan-feng,et al.  Notice of Retraction Application of Network Technique in Transformer Fault Diagnosis , 2010 .

[17]  R. Marquardt,et al.  Modular Multilevel Converter: An universal concept for HVDC-Networks and extended DC-Bus-applications , 2010, The 2010 International Power Electronics Conference - ECCE ASIA -.

[18]  Ronnie Belmans,et al.  Wavelet-based protection strategy for DC faults in multi-terminal VSC HVDC systems , 2011 .

[19]  Jin Yang,et al.  Multiterminal DC Wind Farm Collection Grid Internal Fault Analysis and Protection Design , 2010, IEEE Transactions on Power Delivery.

[20]  Boon-Teck Ooi,et al.  Protection of VSC-multi-terminal HVDC against DC faults , 2002, 2002 IEEE 33rd Annual IEEE Power Electronics Specialists Conference. Proceedings (Cat. No.02CH37289).

[21]  H. Akagi,et al.  Control and Analysis of the Modular Multilevel Cascade Converter Based on Double-Star Chopper-Cells (MMCC-DSCC) , 2011, IEEE Transactions on Power Electronics.