Effects of Short-circuit Fault Current on Temperature Distribution of YBCO Tapes for DC SFCL

Now, with a rapid development of Multi-terminal High Voltage DC (MT HVDC) systems, the short-circuit fault current of DC systems shows an upward trend. A DC resistive type Superconducting Fault Current Limiter (SFCL) installed in the DC system can limit the fault current and it improves the stability of DC system. However, after an attack of short-circuit fault current the superconducting tapes of a DC SFCL may be damaged when the temperature of the tape is too high. Thus it is necessary to investigate the quench and temperature properties of the superconducting tapes under a short-circuit fault current attack. The objective of this paper is to obtain the effects of short-circuit fault current on the temperature distribution and recovery properties of the superconducting tapes of DC resistive type SFCL. YBCO high temperature superconducting tapes was chosen as an investigation sample because recently resistive type SFCL mainly use YBCO tapes. A numerical analysis method was proposed to investigate the quench and recovery characteristics of the YBCO tapes based on thermal conduction theory. This paper concluded that when a 10 m-long YBCO tapes applied in a prospective current of10 kA, rated voltage of250 V DC system, the highest temperature of the tape was 379.2 K and the recovery time was 1.43 s.