Before the alternator starts charging, the blades will be unloaded (Free spinning) and running at higher than normal tip speed ratio, so it makes sense to design your alternator for cutin in 6 or 7 mph winds with a fairly high tip speed ratio. (if you design the blades for TSR of 7, then figure cutin should happen in a 6mph wind at TSR of perhaps 9) - at least this seems to work well for me.
To figure the speed of the tips, you need to figurer the circumferance of the blades (10' blades would sweep a circle with circumferance about 31.4'). Once you know how far a blade travels in one revolution, then you can calculate the rpm required for them to run at the desired TSR and design your alternators cutin speed appropriatly.
Thanks for that explanation of TSR, I had the basic idea I geuss, but still fuzzy, that clears up a couple things for me too.. nothing to lose
Spelin and tpying are my strong points, not electronics.[ Parent ]
