Position sensorless control of a magnetically levitated (Maglev) system

The main focus of this investigation is the development and implementation of a sensorless position estimation method and hysteresis position controller for a laboratory--based Maglev system. The proposed estimation method and controller are first validated through modeling and simulation. This sensorless scheme makes use of the maglev system's magnetic signature, namely, its inductance and requires only active phase current measurements. These measurements are then used along with the phase voltage equation to estimate position information that is in a one-to-one correspondence with the system's inductance. The theoretical aspects of the sensorless scheme are described. Finite element analysis (FEA) as well as experimental measurements have been carried out to obtain static and dynamics characteristics of the system. The proposed sensorless method has been implemented on a DSP microcontroller and the experimental results of this implementation are presented. In addition, simulation results will show the feasibility and effectiveness of this model-based position estimation scheme.