A systematic approach to delay-adaptive control design for smart grids

Communication latency poses a challenge to the operation of control systems in power systems. Specifically, excessive delay between sensors and controllers can substantially worsen the performance of distributed control schemes. In this paper we utilize the parametric feedback linearization (PFL) control to actuate energy storage systems in order to achieve transient stability. A delay-adaptive design capitalizing on the features of PFL control is presented in this work in order to enhance the time delay tolerance of the power system. Specifically, a piece-wise linear delay-adaptive property of the PFL control is investigated. The parameters of the PFL controller are adapted according to the latency value in the cyber component of the grid in order to optimize performance. The enhancements achieved by the proposed delay-adaptive scheme on the performance of the distributed controller are shown when applied to the New England 39-bus and WECC 9-bus power systems following the occurrence of a physical disturbance. Further, numerical results show that the proposed delay-adaptive control is able to tolerate substantial delay without degradation in performance.