Contribution to state control for elevator systems with respect to parameter variation and nonlinearity

The demands on modern elevator motion control are the driving comfort, the precise leveling and the realisation of short running times. Starting jerks and parameter variation causes an uncomfortable run. By the means of a digital state controller there is a better chance to meet the requirements of a wide range of elevator duties. A compromise between costs and technical abilities leads to a solution with a minimum of actual signal detection and low effort on the drive system. Because of these points a control design implementing an observer and a disturbance rejection control is used. Besides this, the parameters of the linearized system are identified, thus allowing the observer coefficients and the gain values to be adapted. The authors discuss the results of this control concept and particularly the investigation of the parameter variation and the problems of nonlinearity of an elevator system