METHOD OF DETECTING AN OPERATING CONDITION OF AN ELECTRIC STEPPER MOTOR

摘要

An electrical stepper motor comprises a magnetical rotor and at least two electromagnetical driving coils for causing rotation of the rotator. A method of detecting an operating condition of the as e.g. a stall state of the electrical stepper motor comprises the steps of connecting one contact pin (P, M) of at least one of the electromagnetical driving coils via a high-impedance resistor (R1, R2) to a defined voltage source during a non-activated state of the driving coil, detecting a voltage induced at the driving coil during the non-activated state and converting the detected voltage into a digital signal, and digitally analyzing the digital signal and deriving an operating condition of the rotor by evaluation of the signal waveform including positive and negative components of the signal.