Design of a Limited State Feedback Wide-Area Power System Damping Controller Without Communication Channels

The wide-area controller (WAC) is used to damp out inter-area oscillations in the power system. Conventionally, to implement WAC in the power system, efficient wide-area communication channels are essential. The performance of the WAC can get degraded with under-performing communication channels. Although, the communication are begin made efficient and redundant, data integrity may pose another threat to the performance of the WAC. In order to subside the dependency on wide-area communication channel, this paper proposes a communication free wide-area controller (CF-WAC) to damp out inter-area oscillations even in the worst scenarios (in terms of communication channels). The CF-WAC is designed based on the state feedback principle and with limited states. The chosen design path can be achieved by using structurally constrained $H_{2}$ -norm optimization. The proposed CF-WAC is designed in a centralized manner and implemented in a decentralized way and yet retain the near conventional WAC performance. The performance of the proposed CF-WAC is compared with full-scale WAC (FS-WAC i.e., conventional WAC), sparsity-promoting WAC (SP-WAC), and reduced-scale WAC (RS-WAC). Simulation studies are carried out on the IEEE 68-bus test system to evaluate the potential of the CF-WAC in damping inter-area low-frequency oscillations by considering different disturbances and communication channel losses.