| Induction motor is widely used in industrial and agricultural production for its simple structure, easy manufacture, reliable operation, lower cost and other advantages. However stator winding turn-to-turn short circuit and phase-deficient occur frequently. When stator winding turn-to-turn short circuit occurs, there exist short-circuit current in the coil between the short circuit winding turns. As time goes by, however the most minor turn-to-turn short circuit can also cause a large area of winding damage, even making the motor stop. Phase-deficient mainly includes one open-circuit of three-phase power and three-phase stator winding. Under the same load, the current in phase-deficient operating state is twice higher than that in normal operating state, and the motor is in overload state. if it has been a long to run, the stator winding will be so overheat that they can be burned. Thus achieving modeling for both stator winding turn-to-turn short circuit and phase-deficient is very important for induction motor to research on electromagnetic characteristic.This paper was supported by program for New Century Excellent Talents in Heilongjiang Provincial University(1254-NCET006), taking a 55 kW three-phase induction motor, Y2-250M-4, as an example, based on the basic theory of the electromagnetic field and motor learning, and under the basic hypotheses, the simulation model of this induction motor is established. Time-step finite element method is used for calculating and analyzing electromagnetic parameter under the case of different level turn-to-turn short circuit and the phase-deficient operation of stator winding respectively.According to the above waveforms and combining with theoretical knowledge,the rationality of the finite element model of the induction motor is verified and the simulation results are corrected. It provides effective mean on quick judgment andaccurate positioning of turn-to-turn short circuit and phase-deficient, and also has certain reference values for the analyzing and positioning of the similar phenomenon occurring in a motor. |
