The first is the simplest test.By handMotorUnscrew from the shaft.as long asPermanent magnet synchronous motorIt is not too big or special motor, it can be twisted by hand.Under normal circumstances, you can use one hand to tighten it for several hundred watts. Even if it is tightened, the power of the normal motor will be greater. Even if there is reluctance torque, there is obvious periodicity, that is, the torque fluctuates at a fixed angle.
In addition, you can manually turn ordinary motors.Assuming you have a good motor of the same model, the hand induction of the two motors should be basically the same.If the motor is not normal after being tightened, the motor is faulty. This kind of test can usually find mechanical faults or short-circuit faults between phases.
There is also a multimeter that can perform most motor inspections.In short, it measures three-phase line resistance, ABC three-phase.You can measure motors between AB, BC and CA.
Very small.Similarly, betterThe method is to compare with ordinary motors.If the three-phase resistance is the same as that of an ordinary motor, it means that there should be no major problems with the stator windings.If there is a problem of virtual soldering or virtual connection or insufficient insulation, it is not necessary.
If they are different, for example, infinity or a large resistance value indicates that the winding is short-circuited, or a small resistance value indicates that the winding is open.
If the phase resistance is very small, it is inconvenient to test. Inductance with the same principle as resistance can also be measured.
If you cannot find any problems in these tests, you must use an oscilloscope to measure the back-EMF.You can turn on the motor and use an oscilloscope to check whether the three opposite potentials are symmetrical.Compared with ordinary motors, permanent magnet synchronous motors have three opposite potentials.The general method is to measure whether the rotor pole is abnormal.
