Transient stability assessment for power system via Lur'e type Lyapunov function

This work presents a transient stability assessment by constructing a Lyapunov function for multimachine power system considering AVR control system represented in the third order transfer function. The proposed Lur'e type Lyapunov function is constructed as a quadratic form of state variables and an integral term which satisfies the symmetric condition and the sector condition, and determined by solving the linear matrix inequality (LMI) derived from the Lyapunov stability theorem. To verify the proposed Lur'e type Lyapunov function, the transient stability assessment for 10-machine test system including AVR control system is shown. The critical clearing times given by the proposed Lyapunov function are compared with those obtained by the numerical integration method, and they are shown to be practical.