Elevator speed detection device and anti-unbalance-loading and self-balancing system based on same

According to the anti-unbalance-loading system and the anti-unbalance-loading control method for the lift car, a weighing sensor serves as input information, a torque sensor serves as detection feedback information, and magnetic fluid is gathered on one side of an electrified coil by electrifying part of the coil, so that unbalance loading of the lift car caused by unbalanced standing of passengers is counteracted. A self-balancing system based on a speed detection device is used for generating braking force through a brake so as to balance the unbalance of a lift car and a counterweight in weight. According to the elevator based on the self-balancing system, under the extreme condition that all other safety measures fail, the elevator car can be braked through self rescue, and the safety of passengers is guaranteed. The reliability and the measurement precision of the speed detection device are improved, the gear and the rack are prevented from being abraded too early due to unbalance loading, and the servic