Symmetric drive method for DC motor in elevator door motor system

The invention discloses a symmetric drive method for a DC motor in an elevator door motor system. An elevator continues to supply power to the DC motor after a door is opened or closed, gate signals of a switching component on an H bridge are converted to symmetric pulse signals with the duty ratio being 50%, and a rotation shaft of the motor is in a static state. Under the state, the torque direction of the rotation shaft of the DC motor is frequently and regularly switched between the forward direction and the backward direction, the motor is in the stalled state, and the stalled state can not be easily changed through external force. Due to the fact that when an elevator landing door is in an opened state and a closed state, the state of the landing door can not be changed by external force manually, the symmetric drive method meets the above requirements, and the reliability of the elevator landing door can be better guaranteed. When the motor is in the stalled state, only the inside resistance of the motor consumes energy, the energy loss is greatly reduced, the motor also has certain moment, and therefore the energy conservation performance of the elevator door motor system is improved.