Start-up and Shut-down Strategies of Hybrid LCC/VSC DC Grids

The line commutated converter based highvoltage direct-current (LCC-HVDC) technology has been widely used for transferring bulk power over long distances in the past decades. In recent years, the voltage level and power capacity of voltage source converter (VSC) based HVDC technology have experienced a great development which provides a possibility of building hybrid LCC/VSC dc systems. In this paper, a four-terminal hybrid LCC/VSC dc grid with two LCCs as the rectifiers and two VSCs as the inverters is proposed. The start-up and shut-down control strategies of this hybrid systems have been proposed with the consideration of the inherent characteristics of the two technologies. The proposed strategies can mitigate the voltage spikes and current surges during the start-up and shut-down processes. The proposed dc grid model and control strategies are developed and validated in PSCAD/EMTDC.

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

[2]  C. Karawita,et al.  Tapping existing LCC-HVdc systems with Voltage Source Converters , 2016, 2016 IEEE Power and Energy Society General Meeting (PESGM).

[3]  Xiao-Ping Zhang,et al.  Basic topology and key devices of the five-terminal DC grid , 2015 .

[4]  Hong Rao,et al.  Architecture of Nan'ao multi-terminal VSC-HVDC system and its multi-functional control , 2015 .

[5]  M. Szechtman,et al.  First benchmark model for HVDC control studies , 1991 .

[6]  Jun Liang,et al.  Asset Management Strategies for Power Electronic Converters in Transmission Networks: Application to Hvdc and FACTS Devices , 2018, IEEE Access.

[7]  Seung-Ki Sul,et al.  A new topology of multilevel VSC converter for hybrid HVDC transmission system , 2016, 2016 IEEE Applied Power Electronics Conference and Exposition (APEC).

[8]  Zhiyuan He,et al.  A DC grid benchmark model for studies of interconnection of power systems , 2015 .

[9]  R. Torres-Olguin,et al.  Offshore Wind Farm Grid Integration by VSC Technology With LCC-Based HVDC Transmission , 2012, IEEE Transactions on Sustainable Energy.

[10]  Dirk Van Hertem,et al.  HVDC technology overview , 2016 .

[11]  Jun Liang,et al.  Analysis of Single-Phase-to-Ground Faults at the Valve-Side of HB-MMCs in HVDC Systems , 2019, IEEE Transactions on Industrial Electronics.

[12]  Chunyi Guo,et al.  Research on the control method for voltage-current source hybrid-HVDC system , 2013 .

[13]  Dehong Xu,et al.  A novel start-up scheme for modular multilevel converter , 2012, 2012 IEEE Energy Conversion Congress and Exposition (ECCE).

[14]  Maryam Saeedifard,et al.  Operation, Control, and Applications of the Modular Multilevel Converter: A Review , 2015, IEEE Transactions on Power Electronics.

[15]  Yanting Wang Yanting Wang,et al.  A Novel Hybrid Directional Comparison Pilot Protection Scheme for the LCC-VSC Hybrid HVDC Transmission Lines , 2016 .

[16]  Xiao-Ping Zhang,et al.  Start-Up Control of an Offshore Integrated MMC Multi-Terminal HVDC System With Reduced DC Voltage , 2016, IEEE Transactions on Power Systems.

[17]  Zheng Xu,et al.  A LCC and MMC hybrid HVDC topology with DC line fault clearance capability , 2014 .

[18]  T. K. Saha,et al.  Hybrid multi-terminal LCC HVDC with a VSC Converter: A case study of Simplified South East Australian system , 2012, 2012 IEEE Power and Energy Society General Meeting.

[19]  A. M. Gole,et al.  Energization and regulation of a hybrid HVDC grid with LCC and VSC , 2017, 2017 IEEE Electrical Power and Energy Conference (EPEC).

[20]  Ning An,et al.  Power Reversal of Hybrid HVDC System , 2015 .