Improving transient stability using generator tripping based on tracking rotor-angle

This paper presents a new method for preparing generator tripping look-up tables. The method uses off-line time domain analysis to build look-up tables of required generator trip arming. The method employs two algorithms. The first algorithm determines if generator tripping is required to attain transient stability for each credible system disturbance and operating condition. Tracking of relative rotor angles is used in the first algorithm. The second algorithm compares the electric power for each generator before and after the disturbance to determine the most appropriate generator tripping for transient stability. The 179-bus WSCC system is used to examine the proposed algorithms. The simulation results show that the proposed generator-tripping algorithms effectively and accurately determine the status of each generator in the system. Also, the simulation shows that tripping the generator that has maximum mismatch in electric power before and after the disturbance stabilizes the system.