Maxon White Paper - High Efficiency Motors
To understand the concept of high efficiency motors, you must first know how to calculate efficiency and the losses associated with the motor components themselves.
The final measured efficiency of a motor is calculated based only on the elements of the particular application they’re used in. For the motors themselves, without a load, manufacturers provide ratings based on standard formulas. To understand high efficiency motors you only need to know what makes them different.
But first, let’s look at the basic concept used for explaining motor efficiency, which says that efficiency is the ratio between the shaft output power and the electrical input power. Shaft output can be measured in horsepower or watts. We’ll use watts for the purposes of this article. The formula most often used is the simple one mentioned above:
ηm = Pout / Pin
ηm = motor efficiency , Pout = shaft power out (Watts) , Pin = electric power to the motor (Watts)
Once you’ve used this formula and found your efficiency – and it’s not 100 percent – it’s time to consider the losses that occurred...