Probabilistic approach-based wide-area damping controller for small-signal stability enhancement of wind-thermal power systems

Based on wide area measurements obtained by phasor measurement units and probabilistic eigenanalysis, this paper presents an approach to the design of a wide-area supplementary damping controller (WASDC) in order to improve the damping of inter-area oscillatory modes in wind-thermal power systems. Novel probabilistic indexes of controllability and observability are proposed to tackle the selection of proper wide-area input signals and the placement of the WASDC. Parameters of the controller are determined by solving an optimization problem that accounts for small-signal stability performance requirements. Numerical results obtained using a benchmark weak interconnected power system are used to survey the possible impact of wind power on system small-signal stability performance, especially in terms of mode controllability and observability, as well as to demonstrate the effectiveness of the proposed controller.