A Study on the Torque Control of a DC Motor with Reduction Gears (2nd Report, Torque Control Based on an Acceleration Controller)

This paper describes a torque control method for a geared DC motor. The torque sensory feedback provides a benefit for the fine torque generation by geared DC motors. However, it reduces the structural stiffness and causes a low response in both torque and position controls. To improve this, a control method based on an acceleration control is proposed. The proposed method uses two control loops. At the inner loop, a high-performance control system for the acceleration of the motor axis is constructed. At the outer loop, a control system with a positive feedback of the load position is introduced. With this structure in mind, the paper suggests that a high-stiffness torque control system can be achieved when the acceleration control system at the inner loop is carefully designed using the disturbance observer.