Which is the higher stator or rotor temperature during motor operation?

Temperature rise is a very important performance indicator of motor products, and the temperature rise level of the motor is determined by the temperature of each part of the motor and the environmental conditions.

From the Angle of measurement, the temperature measurement of the stator part is relatively direct, while that of the rotor part tends to be indirect. However, no matter how it is detected, the relative qualitative relationship between the two temperatures will not change much.

From the working principle of the motor analysis, the motor is basically three hot spots, that is, the stator winding, the rotor conductor and the bearing system, if it is a winding rotor, there is a collector ring or carbon brush part.

From the level of heat transfer analysis, the temperature of each hot spot is different, and it is bound to achieve the temperature balance in the relative sense of each part through heat conduction and radiation, that is, each part is shown as a relatively constant temperature.

For the stator and rotor parts of the motor, the heat of the stator can be directly emitted through the shell, and if the rotor temperature is relatively low, it can also effectively absorb the heat of the stator part. Therefore, the temperature of the stator part and the rotor part may need to be comprehensively evaluated from the size of their own heat.

When the stator part of the motor is heated seriously, and the rotor body is heated less (such as permanent magnet motors), the stator heat is on the one hand to the surrounding environment, but also a part of the other parts in the inner cavity transfer, high probability, the rotor temperature will not be higher than the stator part; When the rotor part of the motor is heated seriously, from the physical distribution analysis of the two parts, the heat emitted by the rotor must be continuously distributed through the stator and other parts, coupled with the stator body is also a heating body, and as the main cooling chain of the rotor heat, the stator part receives heat at the same time through the housing is also cooling. The tendency of rotor temperature to be higher than stator temperature is larger.