Aperiodic Sampling Load Frequency Control of Wind Power-Integrated Power Systems with Packet Losses and Delays under Discrete Time Feedback Interconnection Model

This paper explores the stability assessment and the development of controllers for aperiodic sampling load frequency control scheme for wind power-integrated power systems, accounting for communication delays and packet losses. Firstly, transform the multi-area continuous time model into a discrete time load frequency control model. By incorporating linear operators to manage the uncertainties including communication delays, packet losses and sampling interval within the system, the discrete time load frequency control system is converted into a feedback interconnected system that consists of uncertain operators and linear time-invariant systems. Secondly, the exponential stability condition of the system is given by utilizing the integral quadratic constraint theory and linear matrix inequality technique, which can be used to compute the upper bounds for aperiodic sampled-data intervals and delays. Furthermore, based on the proposed stability conditions, a controller iteration optimization algorithm is designed, which effectively addresses issues related to delays and packet losses. Finally, an example study based on one-area, three-area load frequency control system and IEEE 39-bus system show that the method can obtain larger sampling upper bounds and better control performance than previous methods.