| Canned motor is a kind of special motor. In recent years, it is used widely to deliver the combustible, explosive, corrosive and poisonous medium. For the motor is immersed in the liquid, so there are cans on the surfaces of stator and rotor, which is effective in electric insulating and resistance corrosion. While the motor is running, the magnetic field in air gap cuts the can, which will result in eddy current. The eddy current losses influences on the performance of the motor in some degree. Because of special construction, the distributions of eddy current and magnetic field are complex, and there are still some problems in calculating and analyzing the influences on performances of canned motor.First, the structure and the design characteristics of canned motor were introduced in this paper. The eddy current losses of every structure and performances of motor were deeply studied by computing magnetic field. Canned motors are taken for example, whose performance parameters are calculated for analyzing eddy field and transient field.Secondly,using the 2D Finite Element Method of eddy current field the performance parameters are calculated at starting, ideal no-load, non-ideal no-load and full load conditions. Based on of this, the eddy losses of stator can with different thickness and resistivity was computed and analyzed separately, by which the influence of these parameters on cans'eddy current loss was proposed.Finally, the paper deserves the motor's dynamic performance curves(such as current, electromagnetic torque, load torque and speed)under no-load starting and full-load starting by dynamic finite element method. Mathematic model of load torque and equivalent torque for friction loss are built in the computation which make the starting performances more accordant with practice. In the same time, the maps of magnetic flux density distribution at different time are gained, and analysis the situation of the stator and rotor force. |
PDF Full Text Request