Applications of System Integrity Protection Scheme and Multi-Phase Reclosing of Transmission Lines for Stability Enhancement in Taiwan Power System

Due to generation increase and load growing in recent years, Taiwan power system has faced with some transient instability problems. To tackle out this challenging task, two advanced techniques, including system integration protection scheme (SIPS) and automatic reclosing of transmission lines, are considered in Taiwan power system recently for transient stability enhancement. In facing three-phase faults, the generator rejection scheme (GRS) in SIPS is recommended for quickly maintaining the power balance. The reliability-based GRS with redundant voting mechanisms is conducted to reduce the risk of inappropriate GRS. Detailed settings of the arming threshold of the GRS are investigated by minimizing the risk contributed by unsuccessful operations and accidental operations. For other temporary nonsevere N-2 contingencies, the multiphase automatic reclosing scheme is considered to restore the system in the timing manner. Impacts of unbalanced fault current with respect to the withstanding capability of the generator are also studied. Simulation studies are conducted to validate the effectiveness and applicability of the proposed solution.