Implementation of TLBO Optimised PI^λD^μ Controller for LFC of Nonlinear Reheat Thermal Power System

This article explains the load frequency control (LFC) of dual area interlinked reheat type thermal plant including nonlinearities such as generation rate constraint (GRC) and governor dead band (GDB) by employing fractional order proportional integral derivative (PI^λD^μ) controller. A PID controller is also separately implemented for performance comparison. The parameters corresponding to both the controllers are fine-tuned by application of a teaching learning based optimisation (TLBO) algorithm using integral time absolute error (ITAE) as the fitness function. A comparative performance analysis is accomplished between the two types of controllers by injecting an instantaneous load of 10% in area-1. It is seen that the TLBO optimised PI^λD^μ controller yields better transient response when compared with the other controller. Lastly, the robustness of the TLBO optimised PI^λD^μ controller is verified by applying a randomly varying step load in area-1.