Star wind method v delta

[dinglem]

Does anybody have any info on the use of star winding methods on brushed motors at all? I had heard rumour that Mick Goddard of MG dabbled with this, but have now come across one of his experimental motors. It was labelled as an '8 Special' but in actual fact it has the winding wires terminated and joined together at the pinion end and then one wire joining each com tab, effectively making it a 7.5Turn.

I have never seen anything like it before on a brushed motor.

[jwscab]

I don't know very much about them, but doing a quick sketch up and looking at the timing, with the delta configuration, it appears to me to have two poles of the armature at any given time having current flowing, therefore generating a magnetic field, each sharing the current. with the star or wye configuration, it looks like only one pole would have current flowing at any given time, with all of the current flowing in a singe pole, with a single magnetic field. this is quite simplistic obviously because when in motion there is a lot more complex flux fields going on. But this may possibly create more efficiency at higher rpm? gut feeling tells me this is a weaker motor, but more efficient.

this is intriguing. I may have to wind up two arms with the same wire gauge and turns, and do some rpm and current draw tests.....

[dinglem]

From what i have read online today, star gives lower rpm but higher torque per amp. Certainly fascinating!! Will be good to see some dyno and torque checker figures... it is with my motor builder right now in fact!