An Optimization-based Load Frequency Control in an Interconnected Multi-Area Power System Using Linear Quadratic Gaussian Tuned via PSO

Mismatch between the generation and consumption results in deviation in the frequency of the power system, which negatively influences its operation, reliability, and efficiency. Secondary/load frequency controllers are used for compensating the power mismatch in the time-scale of up to several minutes. The Linear Quadratic Gaussian (LQG) control has been applied for regulating the frequency. However, the parameters in the LQG method are conventionally determined using trial and error methods. This makes the selection process challenging for large power system and cannot guarantee satisfactory response. In this paper, an optimal load frequency control (LFC) method is proposed where the Particle Swarm Optimization (PSO) method is exploited to optimize the selection of LQG parameters for a multi-area system. The performance of the proposed LQG+PSO method is verified on a test-bench three-area system using simulations. It is demonstrated that the proposed LQG+PSO method achieves superior frequency regulation compared to the conventional LQG method.