Electromagnetic Damper Using Brushless DC Motor With Capacitance

Electromagnetic damper using brushless DC motor was developed. The damper has a ball screw mechanism, and a linear motion is converted into rotational motion. The blushless DC motor was installed in tip of the ball screw shaft, and electrical power was generated when the shaft was rotating. Electrical resistance was inserted into terminal of the motor as delta-connected winding, and capacitances were also inserted in parallel. Theory of the torque was introduced with current limit. Force and displacement curves were measured, and resisting force characteristics were confirmed. Dynamic propertied of the damper was investigated.