We are fortunate to have recently collaborated with xx electric vehicle company on a project related to testing and demonstrating the triangular relationship between motor power, speed, and torque, providing a simple and rough basis for companies on how to classify motor products.

For AC motors: rated torque=9550 * rated power/rated speed; For DC motors, the speed is roughly proportional to the armature voltage and inversely proportional to the excitation voltage. The torque is proportional to the excitation flux and armature current.　　

In DC speed regulation, the regulation of armature voltage belongs to constant torque speed regulation (the output torque of the motor is basically unchanged). The regulation of excitation voltage belongs to constant power speed regulation (the output power of the motor is basically unchanged).

T=9.55 * P/N, T output torque, P power, N speed,

The load of a motor can be divided into constant power and constant torque. If constant torque and T remain constant, then P and N are proportional. If the load is constant power, then T and N are basically inversely proportional.

Torque=9550 * output power/output speed power (watts)=speed (radians/second) x torque (Newton meters)

When the power is constant and the speed is fast, the torque is small; Slow speed results in high torque. So when the power is constant, the motor can be classified according to the speed, and testing the speed is quite simpleThe operation, for exampleMX2020RP-B DC Motor Speed Measuring Instrument