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Thread Starter

seayaker

Joined Jan 27, 2009
74
If a simple 2 pole permanent magnet generator were to be commutated without brushes, and operates between 10-50v (before regulation) and between 5-30 amps what kind of scrs or triacs should be used?
 

beenthere

Joined Apr 20, 2004
15,819
This is hard to understand -
If a simple 2 pole permanent magnet generator were to be commutated without brushes
The brushes make the sliding electrical contact to the armature. The commutator is segmented to switch the DC field polarity induced in the armature to produce the properly polarized magnetic field that spins the motor.

Can you explain what you are trying to do a bit further?
 

SgtWookie

Joined Jul 17, 2007
22,230
Our OP is talking about generators, not motors.

Actually, you don't really need SCRs or TRIACs, you could use some bridge rectifiers. How many you'll need depends upon how many coils your generator has.
Have a look at this .pdf document:
http://www.scoraigwind.com/pmgbooklet/itpmg.pdf
Rectification and star/delta topologies are discussed on pages 38 through 44 or so.

Synchronous rectification using MOSFETs and driver circuits would be more efficient than standard rectifiers, but a good bit more complex.
 

Thread Starter

seayaker

Joined Jan 27, 2009
74
I tried full wave bridge rectifiers in every possible way. I was still loosing half my output. I realized what was happening is that the current was flowing against the pole that was being energized in opposite polarity. if you draw the circuit you can see this. I thought I could do it with diodes but a full wave bridge won't work. The poles have to be switched so that current can flow in the right direction in both poles. I used a 2 pole generator for simplicity there are actually 32 coils but it's the same principle. the same as if you took an old generator and removed the mechanical commutator and set out to switch the poles electronically. if any one has any experience with this please respond.
 

Thread Starter

seayaker

Joined Jan 27, 2009
74
Yes I did and thanks, however mine is single phase and the poles have to be reversed I can't just reverse current flow. How does it perform? How many watts at say 25 mph. wind?
 
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