Winding temperature rise is a key performance index of motor products, and plays a crucial role in motor reliability. The factors of the motor body, as well as the operating environment, load changes, etc., may cause the temperature rise level of the motor to change. When the temperature rises, whether it is all manifested as the current increases at the same time, this is also a very worthwhile problem. For the motor body, the size consistency of the electromagnetic conductor, the purity of the conductor, the size of the stator and rotor air gap, the heat dissipation capacity of the structural parts, the overlaying coefficient of the winding core, and the non-alignment of the stator and rotor may lead to the high temperature rise of the motor. Once the motor is manufactured in accordance with the established process and combination, the inherent temperature rise level of its body has become a fact, and in the later use of the motor, the temperature rise of the motor may be increased due to changes in environmental conditions or load and other factors.
The first case: when the load of the motor is overloaded, whether it is intermittent or continuous, it will cause the current of the motor to exceed the rated current to varying degrees, and the most direct consequence is the increase in temperature rise under the condition of increasing current. When the overload is serious, the insulation performance of the motor winding will decline, resulting in the complete collapse of the winding due to insulation aging in a short time. For most motor windings, local interphase, interturn or ground quality failures may occur first due to quality hazards in the manufacturing process.
The second situation is due to the poor ventilation and heat dissipation conditions during the operation of the motor, even if the current of the motor does not exceed the standard problem, but due to the imbalance between heat and heat dissipation, it will also lead to high temperature, especially the motor running in the plateau environment, the problem may be more serious.
In the third case, when the motor runs in a serious undervoltage state, even if the load does not increase, due to the insufficient voltage, the current increases when the motor runs, which is also a relative overload problem, and thus also manifested as a large current and high temperature rise. Therefore, the conformity of the operating conditions of the motor is crucial, and for any motor, the necessary temperature rise margin should also be set aside.
Post time: Mar-21-2025