Grasshopper Optimization Algorithm based Fuzzy PD-PI Cascade Controller for LFC of Interconnected Power System Coordinate with Renewable sources

The frequency instability issue in an interconnected power system due to small disturbances can be overcome by the load frequency control (LFC) scheme using a suitable secondary controller. So, this article introduces a grasshopper optimization algorithm (GOA) based fuzzy PD-PI cascade controller for the LFC study considering a three area interconnected system. Initially, each area of the interconnected power system comprising of a thermal generating unit and further to show the impact of renewable energy sources (RES), a combination of wind generating unit and the solar-thermal generating unit is incorporated along with thermal generating unit in area-1. The study begins with the performance verification of the GOA technique over other techniques. Then to get sure about the selection of objective function, the performance of the GOA-PI controller has been verified by considering two mostly used objective functions i.e. integral time multiplied absolute error and integral square error. Lastly, the performances of the proposed controller have been verified over other controllers for the system with/without incorporating RES.