Designing a 100W Tensile Rotary Power Transmission based Airborne Wind Energy System. Part 2: Generator test

Engineering System Design
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All,

I published Part 2:

This video shows the testing of some cheap generators from AliExpress making sure they perform as advertised (they don’t) or at least do what we need them to do (one does).

Second goal was to find the RPMs needed so we can design our gear to speed up the 120 rotor RPMs to the right generator RPMs.

We also tested with a VESC 4 controller and compared it to a simple rectifier and were adding load cells to measure torque and calculate the efficiency of both designs. But that is for a time after the lock down…

One lesson learned is that if you buy cheap you must test. I have yet to find a component from AliExpress that matches it’s data sheet (if they even come with one).

Stay healthy!
/cb

PD: If you missed Part 1 you can find it here.

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I don’t think the way you test the generator is valid. You are limited in current by the internal impedance of your battery pack . I don’t think you would have same results with 2 x 12 volts battery in parallel . You would have much better results with a foc driver like the vesc. Amps are function of torque (and the capability of your load to accept the current )

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Hi Kitewinder!

You are absolutely right that the current would being limited by the battery - which is why we put plenty of load in parallel to the battery (the beer cooler and multiple load resistors)

I still did not manage to make the Vesc work properly in foc mode with this generator though :frowning:
I assume you have become an expert on this by now :slight_smile: Do you think we could do video chat session and go through some settings? Let me know if/when would work for you!

Thanks!
/cb

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hello Christof, sure with great pleasure. we still use VESC on some SETUP ( for our winding machine for example ) but with BLDC tool, Firmware 2.18 and custom application by flashing a compilated .bin file. What kind of problem did you get ? if you get a disconnection while starting regenerative mode, you could start by adding another capacitor on top of C18 capacitor on VESC. follow this link : http://vedder.se/forums/viewtopic.php?f=5&t=68
you will have a full description of issue.

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