Real time implementation of internal model controller for temperature process

Temperature is one of the most important and significant parameter of control in food processing, pharmaceuticals and in polymerization. Only very control of temperature can be achieved by causing heater power to be simply switched on and off according to an under or over temperature condition respectively. Ultimately, the heater power will be regulated to achieve a desired system temperature but refinement can be employed to enhance the control accuracy. Such refinement is available in the form of proportional (P), integral (I), and derivative (D) functions applied to the control loop. These functions, referred to as control terms can be used in combination according to system requirements. But these controllers offer high overshoot and thus affects the stability The proposed IMC tuning method is efficient in controlling the overshoot and the dynamics of the temperature process. The IMC has a single tuning parameter to adjust the performance and robustness of the controller. The results of the IMC tuning method have been compared with Ziegler Nichols (ZN) closed loop tuning. The performance of the system with both PI controller and IMC are analyzed and its performance measure in terms of Integral square error and Integral absolute error are compared. A remarkable improvement in stability of the system has been observed with IMC tuning justifying its applicability.