Increasing of the accuracy of systems with PID-controllers in the presence of exogenous disturbances

The properties of control systems with PI- and PID-controllers are considered. Dependence of the level of control error on external disturbances is obtained. The use of the PID-controller with higher derivatives of the control error in case the level of control error exceeds the allowable level is proposed. Additional data on the object required to determine the coefficients of the PID-controller is proposed to be obtained using frequency identification.