Have a motor you want characterized? Get in touch.

__Motors Data__

- EX-8 105 Kv (T-Motor U-8 clone), 22V, 40A, Custom Controller
- T-Motor U-8 Pro 100 Kv, 22V, 40A, Custom Controller
- BOMA 48V 1800W Brushless DC Scooter Motor, 50V, 1500W E-bike Controller

Each motor has a PDF summary with some basic data like torque constant, resistance, and test parameters, as well as a few plots. Here's what these plots are, and how you could possibly use the data.

__Efficiency Map__A classic plot in the automotive world. The efficiency map is \(\frac{torque\cdot speed}{voltage\cdot current}\), at every torque and speed point. The efficiency maps are only for 1st quadrant operation: positive torque and positive speed. Otherwise you get divide by zero problems. Here's an example of an efficiency map:

The little "islands" in the plot are annoying artefacts of interpolating a surface from scattered data.

__Loss Map__The loss map is \(|(torque\cdot speed) - (voltage\cdot current)|\) at every operating point. This tells you how much power is dissipated in the motor and controller at a given torque and speed. Useful for determining how hot your motor is going to get. Here's an example loss map:

__Input Power Map__The input power map is just \(voltage\cdot current\) at every operating point. This tells you how much battery or power supply power is required for a given torque and speed. The red boundary on the plot is the zero-power point. On one side of the boundary, the motor draws power from the power supply to achieve the torque and speed, and on the other side of the boundary, power is put back into the power supply, i.e. "regenerative braking". Useful for determining energy requirements for a given task. Here's an example input power map:

This is awesome! More please, please please please

ReplyDeleteEfficiency: motor+controller!!!!! It is big work! It is unique work!

ReplyDelete