Charging system for blackdevil and possibly others

[Nikolatesla]

Hi all ,

My first post here

I'm a nanotrike self builder and a bit of a tech geek . Most of our issues are the same except I have a hanglider wing rather than a canopy above my head.

I use the m25y pull start version and am very happy with it . I'm from down under if that is relevant and mostly fly alone (dont we all anyway?)

A point of interest . When I first flew the black devil I complained to alex and a few others that it was vibrating way too much . I changed anything including the prop is search of the problem.  Magically after about 10 hours use it cleared up and I realized that the motor was simply tight when new . It has been great ever since and the performance on a nano trike /hanglider is excellent 1.3 litres per hour if I fly nice . Usually coastal runs with a bit of lift . I still cant believe how little fuel i use but it is a high performance hang glider ..that might be it .

There has been lots of great help here over the years regarding motor,fuel, electrics and I can perhaps contribute with my current ambition to create a charging source for my trike which has a few instruments . Fuel gauge , cht, egt,gps,which rely on a 11.1 volt bank of lipos.

If i forget to switch off the battery goes flat in 3 hours. And I don't like lipos and their risks  in a flying machine

I tried to wind some extra windings on my black devil ignition coil with not much success and its not wise to steal power from the ignition area in any case .

My current approach is to mount some magnets (2 pairs) on the  drive pulley cooler ring , I don't know what it is called or its purpose other than cooling for the pulley.

Perhaps this has been tried before but I could not find any reference.

I'm taking a powdered iron torroid about 40mm across and 10mm thick and cutting a 12mm section out ,then mounting it solidly to the crankcase bolts allowing the magnets to pass thru the gap creating an ac voltage which will be rectified and regulated .

The magnets are 20mm diameter  and 3mm thick with a hole in the middle, 2 each side bolted to the outer part  aluminum pulley cooler as there is enough space for them to miss the crank case.

https://www.aliexpress.com/item/1005003446576688.html?spm=a2g0o.order_list.order_list_main.10.11251802uLm1xg

The holes need to be exact and the magnets will have to be exact weights for perfect balance but I cannot see why it would not work as I only need 1 amp to do the job.

The challenge is to mount it securely to the crankcase where devcon or something may have to be the bulk of it .

 

I am not a fan of  electric start as my experience with them so far has been problems with quality and needing a dangerous amount of energy on tap.

This may have been tried by others as its rather obvious once one the problem is faced.

 

Lindsay

[Blackburn Mark]

I once considered using a stripped down 170kv outrunner brushless motor (I think that would have given me 36v @ 5500rpm)
The rotor (magnet ring of the outrunner) would be mounted inside the pinion pully and the stator core machined out to allow the 20mm output shaft to clear and mounted on the crank case.
An even simpler way may be to mount the outrunner to scavenge output from the drive belt like a simple tensioner pully.

Picking an appropriate KV rating would save you from messing around with re-winding!

I never explored these options with any great depth but to buy the outrunner and a rectifier for the three phase output... no regulation, charge circuitry or testing so if you do look into implementing something, a nice writeup and pictured would be most welcome



Not sure how long the bearings would last if you use the bell itself as your tensioner pully but it would be very simple.

Edited November 19, 2023 by Blackburn Mark