Asymmetric amplitude Asymmetric wavaform Asymmetric frequency Asymmetric phase
Power fault
Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]
Unbalanced Power Supply
Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]
Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC] State Normal 110.7 A EMF B C A Flux B C A Current B C 150.7 124.3 154.5 Fault 98.1 146.3 147.4 158.7 115.9 116.8 125.8 108.3 157.9 150.4

Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]
On the one hand, the running environment of PMSM is becoming more and more complex so that the PMSM is affected by compound action of the electricity, heat and force. On the other hand, motor supply power can change with the fluctuation of the power system load. These above factors are likely to change the PMSM parameters minorly in long-running so that operation parameters will be further worse if the operating environment has not been improved in time, which leads to the PMSM fault at last.
Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]
The PMSM common faults
Stator fault Stator winding Power fault Rotor fault

Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]

Therefore, study of the change rules of the PMSM parameters in faulty state is important to early eliminate potential safety problems, particularly resume normal operation of the motor.
Torque(NM)
EMF(V)
Current(A)
FluxLinkage(m Wb)
110.7
154.5
150.7
124.3
Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]

Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]

Thanks
Parameters Torque
Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]


Conclusion
(1) The relationship between output torque and PMSM power voltage sag under the fault state is approximately inversely proportion; the output torque fluctuation is obviously increased along with the fault severity degree; the output torque contains 2 times rated frequency harmonics because of the negative sequence component existed in power voltage, which affects the operation performance of the motor. (2) The results of simulation and experiment show that the three-phase current is no longer symmetric under the fault state, and the waveform basically retains its shape of sine; fault phase current fundamental wave amplitude decline scale is more than fault phase voltage sag scale, and the current wave has obviously distorted, in which the 3rd harmonic component increases obviously.
Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]
Compared with other motors, with no armature and slip ring PMSM has the advantages of simple structure and high reliability, and with no current excitation and excitation loss it has high efficiency, and with no rotor fundamental iron loss and copper loss it has high power factor, all which has been widely used in aviation, new energy vehicle, industrial production and so on.
Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]
Balanced Power Supply
Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]
Bearing damage
PM Rotor eccentricity demagnetization
Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]
Advanced Energy technology and Artificial Intelligence International Electrical committee[IEC]
Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC]

Advanced Energy technology and Artificial Intelligence 2015 International Electrical committee[IEC] On the one hand, the running environment of PMSM is becoming more and more complex so that the PMSM is affected by compound action of the electricity, heat and force. On the other hand, motor supply power can change with the fluctuation of the power system load. These above factors are likely to change the PMSM parameters minorly in longrunning so that operation parameters will be further worse if the operating environment has not been improved in time, which leads to the PMSM fault at last.