Comparison between zero power control methods of spiral motor

This paper investigates two zero power control methods for a spiral motor, which are current integral type and external force feedback type. A spiral motor is a linear motor having helical mover and stator that can realize a high thrust force density and high back-drivability. In latest researches, the magnetic levitation control, position control and force control were archived. Additionally, power-saving magnetic levitation is successful by a zero power control. However, a response time of the force control is delayed by the zero-power controller. This paper presents a comparison between zero power control methods through simulations and experiments. As a result, on the force control, external force feedback type zero power control is able to improve the transition time than the conventional method.