A Simulator Study of a Two-Parameter Adaptive System

The use of sinusoidal parameter perturbation applied to a feedback control system to obtain an adaptive scheme which optimizes the system for changes in inputs and/or system parameters is discussed. It is shown that if a parameter perturbation signal is cross- correlated with the system error squared, the corre lator output can be used to adjust the parameter to minimize the mean-square error. Other error meas ures may also be used. Two or more parameters may be simultaneously adjusted, if they are perturbed at different frequencies and each is provided with an independent adaptive loop. A computer simulation of a third-order system having two adjustable param eters was examined for a variety of inputs including random signals. It is shown that the scheme mini mizes the mean-square error in all cases.