Estimation of coefficients in polynomial load torque of induction motor by using tuning function method

DC motor can be replace by Induction motor by controlling speed of induction motor under different conditions but it required fast dynamic response. The speed of the motor must be maintained in permissible range, under varying load condition in the system. But to compensate the speed of motor it requires prior knowledge of the load characteristics. Although external load applied on the machine and environmental conditions changes the characteristic of load parameters continuously so it is very difficult to determine the load parameters. In this paper we have proposed the load to be of polynomial (second order) form and observer is designed for the estimation of load parameter by using tuning function design method. The estimated values along with other measured states are used for the analysis of load parameters. Simulations are done and the results are discussed.