Load frequency control (LFC) play a vital role in order to maintain the frequency regulation in power system. This study shows a comparative analysis of PID controller tuning methods for load frequency control in power system. Six tuning methods namely Ziegler-Nichols Method (Z-N), Tyreus-Luyben Method, Internal Model Control (IMC), Direct Synthesis Method (DS), Robust PID Controller and Optimum PID tuning for set point changes and Disturbance Rejection is adapted to evaluate their performance and used to solve the problem of load frequency control. In this paper higher order single input and single output (SISO) system is carried out with the help of Routh Approximation Method ( - expansion) and Pade Approximation Method to reduce second order model model. The performance analysis is compared to time response specification such as maximum peak overshoot, settling time, rise time and peak time and it is observed that Inter Model Control based PID Controller with first order filter exhibit better performance comparatively.
