Lyaponov function based simultaneous state and parameter estimation in excited DC motor drive

We address the problem of meeting the controller´s requirements for DC motors but under the constraint of omitting the speed sensor: the so called sensorless control problem. We offer an observer based solution and present the design of a robust observer which provides motor speed and armature resistance simultaneously. The concerned observer is designed in such away to assume the overall state observer stability using Lyaponov criterion. The validity of the proposed method is verified by extensive digital simulation results.