A brushless DC motor controller with current-loop control

This paper presents a brushless DC motor controller with current loop control. The controller applies a complementary PWM modulation scheme to the power MOSFET. The current processor employed by the controller could detect the current flow through the motor windings accurately and convert the current to a voltage input to the error amplifier. The controller has 100% duty cycle high side conduction capability and "real" four quadrant torque control capability. It is able to implement a tight torque control for a DC brushless motor to satisfy the need of some servo system which calls for high bandwidth and raid dynamic response.