Analysis of common failures of servo motors

1. The motor generates shaft current

The current in the circuit of shaft bearing pedestal base of motor is called shaft current.

Causes of shaft current:

1) The magnetic field is asymmetric;

2) There is a wave in the supply current;

3) The air gap is uneven due to the rotor eccentricity due to poor manufacturing and installation;

4) The two semicircles of the detachable stator core have gaps;

5) The number of stator cores with fan-shaped lamination is not suitable.

2. The motor is not suitable for light load operation

When the motor runs under light load, it will cause:

1) The motor power factor is low;

2) Low efficiency of motor will cause waste of equipment and uneconomical operation.

3. Causes of motor overheating

1) Excessive load;

2) Missing items;

3) The air duct is blocked;

4) Low speed running time is too long;

5) The power supply has too large wave.

4. Causes of unbalanced three phase current of motor

1) The three-phase voltage is unbalanced;

2) Bad welding or bad contact of a phase branch in the motor

3) Motor winding turn to turn short circuit or phase to phase short circuit to ground;

4) Wrong wiring.