Analysis of R-SFCL With Shunt Resistor in MMC-HVDC System Using Novel R-Q Method

The resistive superconducting fault current limiter (R-SFCL) is considered as a promising protection device to restrict the DC fault current in modular multilevel converter based high voltage direct current (MMC-HVDC) system. One bottleneck of R-SFCL is that it needs to withstand an overcurrent impact during fault, which results in temperature rise and may damage superconducting coils. A shunt resistor connected in parallel with R-SFCL can reduce temperature and protect superconducting coils. However, there are few studies to quantitatively analyze the influence of shunt resistor. This paper applies a novel R-Q method to calculate the quenching resistance of R-SFCL. By combining the R-Q method and finite element method, the system simulation and electromagnetic field analysis are separated, and the calculation feasibility is greatly improved. Then, the effect of shunt resistor in reducing the temperature of R-SFCL is studied. The influence of shunt resistance to the economic and current-limiting performance of R-SFCL is discussed.