Sensorless position tracking for steer-by-wire applications

This paper shall present the design, simulation and implementation of a sensorless observer for three-phase permanent magnet synchronous machines which can be used for automotive steer-by-wire applications. The observer tracks steering transients enabling the sensorless speed/position estimates to be used for backup in case of encoder failure. The sensorless method is based on a high frequency injection approach which estimates speed/position from machine saliencies. The simulation/experimental test scenarios were designed so as to emulate actual steering conditions studied as part of this research project.