My reply is in 3 parts.
Answer to what I thought you were asking:
I can point you toward a 2 stage heater.
It heats air instead of water. It is not 1000W (many single stage units have been built over 1000W). 12V instead of 24V. Adding a 3rd stage is no problem. All the concepts are the same.
Woof's "2-stage Ghurd Super Controller",
http://fieldlines.com/board/index.php/topic,129731.0.htmlI believe you may have a bit of misunderstanding about the electrical aspects.
A dump load controller that operates in PWM can dump 8A or 16A into a '30A heater'.
And it can dump 1A or 3.141592654A or 26.666A into a '30A heater'.
Commercial examples would be the Xantrex C40 or MorningStar TS-45 or TS-60.
Hugh's site had a couple designs. One with relays, one with triacs, maybe more. It's late, I am tired, I looked but didn't find them quickly, but pretty sure they are there somewhere!
http://www.scoraigwind.com/=
Answer to what you may be asking:
The 24V designation made me think it had a battery.
You said "I have spent countless hours searching the web looking for a water heater that would work with a wind turbine without over loading it at slow wind and still use the energy at high wind speeds".
Maybe you are talking about a 'No Battery' system?
If that was your experience with your system that had a battery, and had those issues, then the problem was a crappy controller (which I bet s shiny new dime had a relay).
If there is NO battery, then there is no reason to limit it to 24V.
Probably be better off designating it, say, 24V to 60V (or 90V?). That type of configuration would allow far better use of the high winds.
Again, there are many ways to do that too. Anything from a small bank of op amps, to STAMP or PIC programable ICs, to ICs that allow conversion of on parameter to another (possibly RPM to voltage?), to hacking a $3 6-LED Harbor Freight alternator tester, to about a 1000 other things.
=
I very seriously doubt your Provision
Application would be worth the cost of attempting to get a Patent. I doubt there is anything in it not obvious to someone in the field.
The cost of a defendable patent is not cheap. The market is limited. Bad investment to return ratio.
I am not clear on "I could retire from pulling wrenches and build water heaters."
Meaning build the control circuits, the heating elements, or the entire assembly with the tank?
Might be a market for it, but I doubt it would be worth thowing money at (genuine) patent attorneys.
Certainly not enough market to sell your impact wrench on ebay.
Curious about the public disclosure status.
This is like pin the tail on the donkey.
We know you THINK you have something that looks like it might be a donkey. That's all we know.
Hard to accurately pin the tail on the donkey when we don't know if there is actually any donkey involved.
(if you know what I mean)
There are more than a few members here with patents.
They may speak up if there was more info to work with.
G-