Identification and control of high-rise elevators

Abstract

Building elevators for high-rise buildings pose significant engineering challenges for modeling, identification, validation and control of elevator systems. The paper focuses on integration of identification, validation and control for high-rise elevator systems. Unlike low rise towers, rope dynamics play a significant role in overall system dynamics. In the context of identification, long rope lengths manifest themselves in terms of low frequency lightly damped modes. In addition an elevator system has a large number of parameters to be identified. These factors make empirically based system identification difficult. We jointly solve the identification and model-validation problem by partly relying on intuition to reduce the complexity. We present a novel modal analysis approach to validation. We pose the following question: what are the optimal values of model parameters within predetermined ranges, required to validate the predominant mode and mode-shapes of the physics-based model with the experiment. Consequently, we have a system model for the high-rise elevator with parametric and nonparametric uncertainties in the context of control.