Study On Method Of Designing Solid Rotor Brake Motor

A solid rotor brake motor is composed of a solid rotor induction motor and an electromagnetic brake. Since having high starting torque and small starting current, solid rotor induction motor is suitable for starting with heavy load. With excellent heat stability, it can work in braking state for a long time. The vibration is small and magnetic noise is very low when motor is operating. Rotor is simple and firm, so the motor can be used as the drive of AC moment motor and grab. The electromagnetic brake is fixed at the end of motor to make it stop, which can satisfies the brake requirement of moving equipments.Because of low efficiency, low power factor and inadequate design method, the application and development of solid rotor induction motor are restricted to a certain extent. The electromagnetic brake is supplied by AC power which can cause vibration and eddy current. Eddy current increases power loss, and makes efficiency low. Therefore, the magnetic field and eddy current in motor and brake are computed and analyzed based on field-circuit coupled finite element theory, and the method to design solid rotor induction motor is studied and validated.Firstly, permeating depth method and multilayer theory method are applied to study the design method of solid rotor induction motor. Rotor parameters and performance parameters are computed by these two methods respectively. By comparing the computed results with experimental data, the application range is summarized.Secondly, a two-dimensional field-circuit coupled model of solid rotor induction motor is set up, the magnetic field and eddy current field in it are computed and analyzed. A new end-region coefficient and the corresponding correcting method are presented to consider the effects caused by end region. The computed results are corrected to obtain more accurate motor parameters. Performance experiments are taken to validate the computed results. The high accuracy of correction coefficient and high validity of correcting method are proved by comparing the computed results with experimental data.Thirdly, a new structure of electromagnetic brake is presented. A field-circuit coupled model of electromagnetic brake is set up. The electromagnetic field in it is computed and analyzed. Two types of electromagnetic brakes with different structures are analyzed by comparing with each other, and the better performance of new structure electromagnetic brake is validated. Finally, factors having impacts on electromagnetic force and power loss are studied and summarized.