Measuring rotation of direct current electric motor by coupling capacitance connected to motor terminal, amplifier and detector of gradient which produces pulses proportional to angular displacement

摘要

A direct current electric motor (M) is supplied by a potential (Vs) through a resistor (R) which may represent control diodes or parasitic resistance. A coupling capacitor (C) is connected to the non earthed motor terminal and supplies an amplifier (1) and gradient detector (2). The gradient detector produces pulses due to commutation and after initialization these are interpreted by a microcontroller as angular displacement of the motor