What are the two main types of motor performance?

Update:18 May 2020
Summary:

  The main performance of the motor is divided int […]

 

The main performance of the motor is divided into: one is the starting performance; the other is the running performance:

Starting performance: starting torque, starting current. Generally, the greater the starting torque, the better, and the lower the starting current, the better. In practice, the starting torque multiple (starting torque to rated torque ratio Tst / Tn) and the starting current multiple (starting current and rated The current ratio Ist / In) is evaluated. When the motor is at rest, the ratio of the torque that can be provided at a certain current value to the rated torque characterizes the starting performance of the motor. Operating performance: efficiency, power factor, winding temperature rise (insulation level), maximum torque multiple Tmax / Tn, vibration, noise, etc. The greater the efficiency, power factor, and maximum torque multiple, the better, while the smaller the winding temperature rise, vibration, and noise, the better.

Starting torque, starting current, efficiency, power factor and winding temperature rise are collectively called the five major performance indexes of the motor.

Efficiency η: The ratio of motor output mechanical power to input electric power, usually expressed as a percentage.

Power factor COSφ: the ratio of motor input effective power to apparent power.