Influence of Design Methods a Discrete Model of Separately Excited DC Motor on Parameters Estimation

Abstract

The authors have developed the methods of preparing the difference schemes required for dynamic identification of the parameters of a DC motor as an object of the electric drives with control system during idling start-up. A system of differential equations describing the separately excited DC motor is reduced to the system of difference equations for constructing the discrete model. The authors have used three methods: direct difference, bilinear transformation method and multipoint approximation for writing the difference equations system. The estimations of the parameters of the discrete model based on the linear algebraic equations system applied this way were obtained by the matrix method. Comparing the estimates obtained the authors detected the influence of the methods of constructing the object discrete model on the error in the parameters' estimations obtained.