Comparative Analysis of MIT Rule and Lyapunov Rule in Model Reference Adaptive Control Scheme

Adaptive control involves modifying the control law used by the controller to cope with the fact that the parameters of the system being controlled change drastically due to change in environmental conditions or change in system itself. This technique is based on the fundamental characteristic of adaptation of living organism. The adaptive control process is one that continuously and automatically measures the dynamic behavior of plant, compares it with the desired output and uses the difference to vary adjustable system parameters or to generate an actuating signal in such a way so that optimal performance can be maintained regardless of system changes. This paper deals with application of model reference adaptive control scheme and the system performance is compared with Lyapunov rule and MIT rule. The plant which is taken for the controlling purpose is the first order system for simplicity. The comparison is done for different values of adaptation gain between MIT rule and Lyapunov rule. Simulation is done in MATLAB and simulink and the results are compared for varying adaptation mechanism due to variation in adaptation gain.