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[VAWT] A DIY method for determining the BLDC machine constant

Not all manufacturers publish data of the machine constant for BLDC machines, relating the produces torque to current through the machine. This constant is usually called machine constant too. In the wind turbine project we used a hub-BLDC machine intended as a hub-motor for bicycles as a generator. Neither the manufacturer nor the supplier could provide this machine constant. We didn't have access too a dynamometer for testing it neither. Furthermore, the hub BLDC wouldn't likely fit into most dynamometers anyway.

Method overview 

Therefore I developed a method to determine this constant that is fairly economical and doesn't require much specialized equipment. I started to dig deeper and deeper into the grounds of knowledge, and the what started mostly as extensive self note became something more like a non-revised report.

Read the Step-by-step instruction summary here

Read the full report here

Any comments or feedback regarding the report content is appreciated. Here is a commentable version of the report, without pictures. You can also submit a commend via this post. 


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