Abstract: This paper deals with the controlling of the non-linear system using fractional order IMC-PID controller. The IMC-PID controller does good set-point tracking but poor disturbance response essentially for the process which has a minute time-delay/time-constant ratio. The study of different methods of IMC design and IMC based PID controller has been intended for a plant transfer function to include the advantages of PID controller in IMC. The intended of fractional order PI?D controller in which the orders of the Integral (I) and Derivative (D) parts ? and are fractional. The purpose of introduction of these two parameters is to ensure the robust performance of the system. The IMC is used to handle non-integer system with time delay. IMC PID controller has been designed for a plant transfer function to incorporate the advantages of PID controller in IMC. In order to reduce the number of tuning parameters and effects of time delay, the fractional order internal model control scheme is used.

Keywords: Fractional order, IMC, PID, Non-linear system, time delay.