Hi, I have 2 questions for which I can not find an answer (I hope you will be so kind to help me)
1) An asynchrounous motor with phase rotor is started and it works under nominal load. But rotor frequency is approximately 2 times smaller than nominal frequency. What could be the problem and why?
In my opinion the additional resistances in this case are not turned off completely and it causes rotor current to be smaller, therefore torque is also smaller and speed is dropping... Can this be true?
2) If an asycnhrounous motor is working properly under nominal load, and suddenly 1 phase dissapears in stator windings, what will happen? (for example, rotor changes it`s frequency, or motor stops)
Again, in my opinion nothing will happen, because then current in other two phases will get stronger and provide same torque as in 3-phase...
Thanks!
1) An asynchrounous motor with phase rotor is started and it works under nominal load. But rotor frequency is approximately 2 times smaller than nominal frequency. What could be the problem and why?
In my opinion the additional resistances in this case are not turned off completely and it causes rotor current to be smaller, therefore torque is also smaller and speed is dropping... Can this be true?
2) If an asycnhrounous motor is working properly under nominal load, and suddenly 1 phase dissapears in stator windings, what will happen? (for example, rotor changes it`s frequency, or motor stops)
Again, in my opinion nothing will happen, because then current in other two phases will get stronger and provide same torque as in 3-phase...
Thanks!