A Transfer-Function Approach to the Analysis and Design of Zero Power Controllers for Magnetic Suspension System

Abstract

A transfer function approach is applied to the analysis and design of zero power controllers for magnetic suspension systems. The general structures of controllers achieving zero power control are derived for both current-and voltage-controlled magnetic suspension systems. For the former-type system, there are two basic approaches: feeding back velocity signal and introducing a minor feedback of the integral of current. Both the approaches are applicable to the latter-type system. In addition to them, the position-sensorless approach also realizes zero power control automatically. A direct synthesis method for zero power control is developed based on the analysis. Several experiments are carried out with a single-degree-of-freedom model. The experimental results show the effectiveness of the proposed synthesis method. © 2001, The Institute of Electrical Engineers of Japan. All rights reserved.