Lyapunov function for multimachine power systems with generator flux decay and voltage dependent loads

This paper considers the direct stability analysis of a power system in which both active and reactive power flows are considered. Flux decay action is included in the generator model. The load is modelled with complex load power as a function of both bus voltage magnitude and frequency. The network model is structure preserving. The stability analysis is based on the use of an energy-type Lyapunov function. The results substantially generalize those given earlier by Bergen and Hill¹ where bus voltages were assumed to be constant, and flux decay was neglected.