Tweet
Message from Lee to Sephiroth regarding relay coil in the trigger circuit:
What he says has got me thinking... even I would expect the rpm to be lower with shorter pulses so perhaps it is something about my motor which benifits from the relay coil...
I think Lee may have found the answer. Possibly because my rotor is very light, has a small diameter, little friction and three coils the torque/wieght ratio is so high it goes into "rotor runaway"... and of course the amp draw generally increases as the rpm increases.
The shorter pulses reduce the torque (as indicated by the slower acceleration) to a point where less is wasted. So it is more efficient.
SO.... new challenge. I want to add drag to the rotor in a way that will provide extra charge to the batteries... tried adding a few coils around the perimeter of the rotor but they only charge the cap up to 6 volts so need bigger recovery coils... will let you guys know if anything interesting happens!
until then, I think this is still a pretty good modification for small rotor ssgs...
Hello Sephiroth,
I have been working on a video presentation regarding my forwarded post to the energetic forum.
Congrats on you demonstration video!! The choke in the trigger winding clearly has a benefit in your set up. Unfortunately, what works for one person may not work for the next, this is the problem with home brew SSG's. Anything that reduces current draw on the front end while maintaining the same charge rate, more or less, is certainly a modification in the right direction.
As you will see in my video, when I get it finished, my RPM was reduced. The single coil unit I used to demonstrate your experiment was already well balanced regarding magnet spacing and coil construction. Also, the only inductor I had with enough inductance to make a difference was the coil of a 12v relay. This relay had quite a high resistance in the coil due to the fact that it had a low holding current, around 30mA.
What the video does show is the affect your modification has on rotor timing and transistor duty cycle in a very visual manor. My setup may have shown the effect to extreme, one of the problems I had with big coils around very small light rotors was rotor runaway, sometimes it is beneficial to introduce a small amount of drag and, on the other hand, sometimes it isn't.
I can only suggest that you engage in some load tests to see if the choke in the trigger improves battery charging efficiency relative to energy input. It's important to take relative measurements as you could miss a percentage increase at a lower energy input and miss it because your batteries "seem" to take much longer to charge.
Kindest Regards Lee....
PS. Feel free to re post this to energetic if you wish. I joined over a week ago but I'm still
I have been working on a video presentation regarding my forwarded post to the energetic forum.
Congrats on you demonstration video!! The choke in the trigger winding clearly has a benefit in your set up. Unfortunately, what works for one person may not work for the next, this is the problem with home brew SSG's. Anything that reduces current draw on the front end while maintaining the same charge rate, more or less, is certainly a modification in the right direction.
As you will see in my video, when I get it finished, my RPM was reduced. The single coil unit I used to demonstrate your experiment was already well balanced regarding magnet spacing and coil construction. Also, the only inductor I had with enough inductance to make a difference was the coil of a 12v relay. This relay had quite a high resistance in the coil due to the fact that it had a low holding current, around 30mA.
What the video does show is the affect your modification has on rotor timing and transistor duty cycle in a very visual manor. My setup may have shown the effect to extreme, one of the problems I had with big coils around very small light rotors was rotor runaway, sometimes it is beneficial to introduce a small amount of drag and, on the other hand, sometimes it isn't.
I can only suggest that you engage in some load tests to see if the choke in the trigger improves battery charging efficiency relative to energy input. It's important to take relative measurements as you could miss a percentage increase at a lower energy input and miss it because your batteries "seem" to take much longer to charge.
Kindest Regards Lee....
PS. Feel free to re post this to energetic if you wish. I joined over a week ago but I'm still
I think Lee may have found the answer. Possibly because my rotor is very light, has a small diameter, little friction and three coils the torque/wieght ratio is so high it goes into "rotor runaway"... and of course the amp draw generally increases as the rpm increases.
The shorter pulses reduce the torque (as indicated by the slower acceleration) to a point where less is wasted. So it is more efficient.
SO.... new challenge. I want to add drag to the rotor in a way that will provide extra charge to the batteries... tried adding a few coils around the perimeter of the rotor but they only charge the cap up to 6 volts so need bigger recovery coils... will let you guys know if anything interesting happens!
until then, I think this is still a pretty good modification for small rotor ssgs...
as that thread is strictly for his motor design ideas.
)
What kind of reed switch in particular would be an allaround good r.witch to use for the ssg's? 
Comment