Research on energy saving control scheme of elevator running based upon the current angle &thetas; in vector space

This article introduces an energy saving control scheme of elevator running based upon the current angle θ in vector space, and the proof of the stator current minimization algorithm is presented. This control scheme does not increase the systematic hardware cost. Through adjusting magnetizing current according to the motor load, the stator current is minimized, thus minimum motor loss is achieved. Computer simulation based upon vector space minimum magnetizing current is carried out on asynchronous motor light running system. When the load ratio is 14%, the energy saving ratio can be up to 9%. Simulation result indicates that, when the elevator is under light load conditions, the proposed control scheme not only reduces the motor energy loss but also decreases the surge of the electromagnetic torque.