Method for protecting motor from overheating

A method for protecting a motor from overheating, the method comprising:

• 1) running the motor in a given parameter P and detecting a real-time temperature R of the motor;
• 2) comparing the real-time temperature R with a plurality of set temperatures, the plurality of set temperatures comprising an overheating protection temperature Rm, a shutdown temperature Rmax and a recovery operation temperature Rmin, and Rmin<Rm<Rmax;
• 3) according to a comparison result in 2), controlling the motor to operate at an initial current value I0, or operate in a reduced current value with respect to the initial current value I0, or stop running;
• and
• 4) when the real-time temperature R meets the condition:
• Rm<R<Rmax, running the motor in an overheating protection mode, where the motor operates at a current value I lower than the initial current value I0, and the current value I decreases with an increase of the real-time temperature R;
• and in the overheating protection mode, when the real-time temperature R begins to decrease, the current value I no longer decreases and the motor continues to operate at the current value I;
• when the real-time temperature R decreases to the recovery operation temperature Rmin, the motor quits the overheating protection mode, the current value recovers to the initial current value I0, and the motor runs under the given parameter P.