Switching Excitation Controller for Transient Stability of Multi-Machine Power Systems

This paper proposes a switching excitation controller to enhance the transient stability of multi-machine power systems. The switching excitation controller (SEC) consists of a conventional excitation controller (CEC), a bang-bang excitation controller (BEC), and a state-dependent switching strategy. Moreover, the SEC switches between the CEC and the BEC based on the switching strategy. The BEC is designed as a second-order bang-bang funnel controller, which can quickly switch the excitation voltage between the upper and lower limit values. To verify the performance of the proposed controller, simulation studies are undertaken in a 10-generator 24- bus power system, which includes the case of a three-phase-to-ground fault. The results reveal that the SEC can achieve the goal of transient stability enhancement.