Applying structured singular values and a new LQR design to robust decentralized power system load frequency control

The design of decentralized robust load frequency control for interconnected power systems is studied in this paper. It is shown that, subject to a condition based on structured singular values (SSVs), each local area load-frequency controller can be designed independently. The robust stability condition for the overall system can be easily stated to achieve a sufficient interaction margin (introduced in this paper), and a sufficient gain and phase margin defined in classical feedback theory during each independent design. Within this general framework, each local area controller design is based on a new linear quadratic regulator design approach.