State Key Laboratory of Alternate Electrical Power System With Renewable Energy Sources (North China Electric Power University), Beijing 102206, China
With the development of offshore wind power and the increase of installed capacity of regional wind power, large-scale renewable energy sources are intergrated to the grid with modular multilevel converter based multi-terminal direct current(MMC-MTDC), which has become a trend of wind power grid intergration. However, the fault ride-through coordination of the multi-converter system with MMC-MTDC and permanent magnet generator and its fault characteristic analysis have not been effectively resolved, thus needing urgent research. First, the traditional fault ride-through strategy of MMC-MTDC system intergrated wind power is optimized in this paper, and a feasible ride-through strategy is put forward. Furthermore, combined with the respective fault analysis of multiple converters, the principle of power transmission balance between converters and permanent magnet generator converters is used to propose an analytical expression of steady-state short-circuit current, which can fully reflect the AC fault characteristics of the MMC-MTDC system intergrated wind power. The problem that the fault characteristics of the cascaded multi-converter are difficult to analyze is solved. Finally, based on the actual engineering parameters, modeling is carried out on the PSCAD/EMTDC simulation platform, and the simulation results verify the effectiveness of the proposed fault ride-through control and the correctness of the steady-state short-circuit current calculation formula.
This work is supported by National Key R&D Program of China (No. 2018YFB0904104) and State Grid Corporation of China (No. SGHB0000KXJS1800685).
|||QIN Jishuo, JIA Ke, YANG Bin, et al. Short-circuit Fault Current Analysis of AC Transmission Line of MMC-MTDC System for Wind Power Intergration[J]. Automation of Electric Power Systems,2021,45(14):47-55. DOI:10.7500/AEPS20201020002|