A Gain Scheduling Control Framework for Mitigation of Time Varying Network Latency in Autonomous AC Microgrids

Abstract

AC microgrids, being cyber-physical systems, rely heavily on communication networks to achieve their control objectives. However, the possibility of communication delays due to protocol-based errors, external noise addition, etc., raises suspicion on the reliability of communication infrastructure. This, in turn, makes the control architecture of the microgrid look complex and vulnerable. To address this problem, this work designs a consensus-based distributed secondary controller within the hierarchical control structure to achieve improved voltage and frequency regulation along with active and reactive power sharing while accounting for time-varying communication delays. Also, this work proposes a gain scheduling control in the secondary control that can effectively reduce the effects of communication delay over the performance of the hierarchical control structure. Our results show that this can efficiently eliminate system vulnerability to large values of time-varying delays. The efficacy of the proposed controller is also investigated in real-time with the help of a hardware-in-loop (HIL) setup.