Position information based disturbance and speed observer having no influence on overflow of counter

The position information based disturbance observer estimates both disturbance torque and motor speed by using the informations of rotor position and motor current. It is expected to be useful and practical for the several industrial drive systems. However, this disturbance observer always has influence on overflow of encoder pulse counter. In order to overcome this problem, this paper proposes a new position information based disturbance and speed observer, which has no influence on overflow of encoder pulse counter. The simulation and experimental results show that the speed control system based on the proposed observer well regulates the motor speed and the motor torque stably and quickly on condition that the encoder pulse counter has the overflow phenomena