DSP Implementation of Rotor Position Detection Method for Hybrid Stepper Motors

To improve the dynamic performance of the stepper motor it can be driven with a closed loop control. For sensorless control, initial rotor position detection is one of the serious problems. At standstill, if the rotor position is inaccurately detected, the stepper motor can move in the wrong direction or do not start at all. The method that uses inductance saliency to detect the initial rotor position is very suitable for hybrid Stepper motor (HSM) which is highly saturated. This paper will present experimental results for the initial rotor position estimation. At standstill, a sequence of voltage pulses is applied and the measured peak current gives information about rotor position. The DSP System used for the implementation is based on the powerful DS 1103 controller board from dSPACE. It allows programming dynamic real-time systems using Matlab/Simulink environment