Optimal load frequency control system for two-area connected via AC/DC link using cuckoo search algorithm

Abstract

Background

Interconnection of different power systems has a major effect on system stability. This study aims to design an optimal load frequency control (LFC) system based on a proportional-integral (PI) controller for a two-area power system.

Methods

Two areas were connected through an AC tie line in parallel with a DC link to stabilize the frequency of oscillations in both areas. The PI parameters were tuned using the cuckoo search algorithm (CSA) to minimize the integral absolute error (IAE). A state matrix was provided, and the stability of the system was verified by calculating the eigenvalues. The frequency response was investigated for load variation, changes in the generator rate constraint, the turbine time constant, and the governor time constant.

Results

The CSA was compared with particle swarm optimization algorithm (PSO) under identical conditions. The system was modeled based on a state-space mathematical representation and simulated using MATLAB. The results demonstrated the effectiveness of the proposed controller based on both algorithms and, it is clear that CSA is superior to PSO.

Conclusion

The CSA algorithm smoothens the system response, reduces ripples, decreases overshooting and settling time, and improves the overall system performance under different disturbances.