Comparison of PI controller performance for first order systems with time delay

Delays appear often in all real world engineering systems. delay systems have the property that the rate of variation in the system state depends on the previous states also. they are frequently a source of instability and poor system performance. in order to get the required performance from the delay system controller design plays a vital role. because of the robust nature,easy structure proportional integral derivative (pid) controllers are extensively used in many industrial loops. parameter tuning of the pid controller is an essential task. numerous industrial processes,whose transfer function is of first order,can be easily controlled with pi controllers. this paper presents the comparative analysis of an approach based on lambert w function for pi controller design for first order systems with time delay among smith predictor (sp) and zeigler-nichols (zn) methods of design. performance of the considered methods in terms of various performance specifications through simulation results has been illustrated. results demonstrate that the lambert w function based pi tuning results in adequate performance compared to other methods with respect to parameters settling time,overshoot,errors,etc. © school of engineering,taylor’s university.