Enhancement of Multi-machine Power System Transient Stability Using Superconducting Fault Current Limiters with YBCO and Bi-2212

One of the worst types of fault that a power system should be designed to withstand is a short circuit. Within the various types of fault current limiters, the superconducting fault current limiter (SFCL) has an extremely fast current limitation. The rapid switching action and the self-sensing nature of the superconductor make SFCLs particularly attractive in fault protection. This very fast time response is potentially shorter than those of the classical current limiters. There are two common types of SFCLs resistive-SFCL which is inserted directly in series with the circuit to be protected and inductive-SFCL which is a transformer shorted by superconducting tube. Yttrium barium copper oxide (YBCO) and Bismuth strontium calcium copper oxide (Bi2212) superconducting materials were used with both types. This paper presents a comparison study between the impacts of installing resistive-SFCL and inductiveSFCL with YBCO and Bi-2212 materials on the transient stability of multi-machine power system during large disturbances. Because SFCLs have extremely fast current limitations, they have better ability to maintain the synchronization of the generators in the power systems. The resistance of SFCLs during fault conditions helps in increasing the output electrical power and hence decreases the accelerated power of the rotor that enhances the stability of the generators. Simulation studies are performed using 9-bus 3-machine system. All analyses were performed using MATLAB package. KeywordsSuperconducting fault current limiter, transient stability, YBCO, Bi-2212, multi-machines