What Causes Electric Vehicle Motors to Overheat?
2 Answers
Electric vehicle motors overheat for the following reasons: 1. Abnormal bearing operation: The working condition of bearings can be judged by auditory and temperature experience. If a hissing sound is heard, it indicates insufficient lubrication in the bearings. The motor should have its lubricant replaced approximately every 3,000 to 5,000 hours of operation. 2. High power supply voltage increases excitation current: Excessively high voltage can endanger the motor's insulation, posing a risk of breakdown. When the power supply voltage is too low, the electromagnetic torque decreases. If the load torque isn't reduced, the rotor speed becomes too low, increasing the slip rate and causing the motor to overheat due to overload. 3. Abnormal vibration or noise in the motor can easily cause overheating: This type of vibration is typically caused by the motor itself, often due to poor rotor dynamic balance, bearing defects, bent shafts, misalignment between end covers, frame, and rotor, loose fasteners, or improper motor installation on uneven foundations. It may also be transmitted from the mechanical end, requiring specific troubleshooting based on the situation.
I noticed that the electric car motor was getting hot, and common causes include excessive load. For example, climbing steep slopes or carrying heavy loads can make the motor work hard and generate heat. Another major issue is an ineffective cooling system: the fan not spinning, cooling fins clogged with dust, or insufficient coolant, causing heat to accumulate when it can't dissipate. Poor driving habits, such as frequent rapid acceleration or braking, also increase the motor's burden. Once, during a long drive on a mountain road, the motor got extremely hot, and it turned out to be due to dust buildup in the vents. From a safety perspective, overheating can lead to fires or component damage. I would immediately stop to let it cool, check ventilation, and if necessary, take it to a professional shop to clean the cooling system. Regular maintenance of the cooling fins can prevent this issue. In short, avoid overloading and aggressive driving—safety first.
