Nonlinear state estimation using interval computation in PMSM state observer simulation

Abstract

The main idea presented in this paper is to use interval analysis technique on state estimation of nonlinear dynamic system, in this concrete case the PMSM (Permanent Magnet Synchronous Machine). PMSM drives offers in comparison to other drives several advantages but it is necessary to have knowledge of actual rotor position and actual speed of rotation for precise control. Measurement of these state variables is technically or financially unnecessarily consumptive. These data are usually obtained by state observers, in most cases by extended Kalman filter or his modifications. Unfortunately, in many cases this is insufficient. That is why other methods of state estimation are being researched. One of these methods is interval analysis in which results are not points, but intervals. Advantage of this is that these intervals are guaranteed.