I try to make it selfrunning like show in scheme, with black diode and without it, but it not selfrunnig. I use 16 V 10000 uF capasitor.
If on one stator coil wind other coil and conect to source trought diodes, and from 12 V and then disconct 12 V, it stop seems slower, than without it.
I think to chare battery beter not modifi fan, but wind on each coil, stator pole, other coil and from it trought diodes get + and - and chare with it battery.
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