Recently the fractional calculus has received extensive attention. Fractional order controller is widely used for different applications. In this project Three Degree Of Freedom Fractional order Integral Derivative (3DOF-FOID) controller has been proposed. The controller was designed; control the deviation in frequency and Tie-line power for two area hydro thermal power system. This project uses integral square area error as a performance index for design of 3DOF- FOID controller. The 3DOF-FOID controller parameters are optimized by using Biogeography algorithm. The performance and robustness of the proposed controller has been compared with the other classical controllers under different loading conditions. It is shown the performance of 3DOF-FOID controller optimized with Biogeography algorithm was better than classical controller in terms of transient stability.

Keywords : Deregulated Power System – LFC -AGC –Biogeography Optimization (BBO) -3DOF-FOID Controller