Active RIS-Assisted Communication and Control Co-Design for LFC in Smart Grids

Wireless networked control systems integrate wireless communication into load frequency control systems by connecting phase measurement units (PMUs) and controllers within modern smart grids. However, balancing control performance and wireless communication cost, particularly when obstacles disrupt channels between PMUs and controllers, is a major challenge. To alleviate this challenge, this letter formulates a multi-objective function that simultaneously minimizes control and communication costs, with PMU power consumption as the communication cost and linear quadratic regulator (LQR) cost as the control cost. Moreover, to enhance channel quality, we employ active reconfigurable intelligent surfaces (RIS) to modify the propagation environment and amplify transmitted signals. Simulation results demonstrate the proposed method’s effectiveness in reducing both PMU’s transmit power and LQR cost, with active RIS outperforming passive RIS and amplify-and-forward relay.