governing of torque or rpm

[SteveH_IN]

Hi all, new to the forum and hoping I might get some ideas for a project I am working on, not an Engineer or very well technically educated, so please go easy on me .

What I wish to do is to build a waterwheel which will supply electrical power to my home. I have been doing some research in some old books on waterwheels, since it is an old technology not used much any more, being replaced by water turbines for the most part. Obviously, the waterwheel is going to turn at different speeds, depending on the flow of the river which varies by season and such. But electric generator heads don't like variable RPM's to them as far as I know, although someone who builds waterwheels answered a few questions and one of them was that once connected to load, the generator head would 'govern' the wheel to a certain degree.

I was thinking of using an undershot waterwheel directly in the stream, which is why you would get variation in the turn speed of the waterwheel. In the old books, they often talked about using a 'sluice' I would supposed you call it, and they had ways to raise and lower the sluice gate to admit more or less water into the sluice - thereby regulating the amount of water getting to the wheel and adjusting it's RPM's. But often these were adjusted by hand, you had to go to the waterwheel and adjust the gate manually, although I think there were some 'automated' attachments you could use for raising and lowering the sluice gate 'automatically' to adjust flow to the wheel.

I was just thinking that with all our new technology there should be some way to automate this process, and I would like to do so, so that I don't have to go to the wheel all the time and make adjustments.

I don't know the wisest course of action to follow when it comes to governing the RPM's either. Build something onto the wheel that would act like a centrifugal clutch or something of that nature, and regulate it's turning there? Or use something at the other end to govern the turning of the pulleys?

I have kind of been wracking my brain here, and I have thought of a few possible solutions, but I don't know how well each one would work. Also keep in mind, I don't know the river or the site on the river I will be using, so I don't know if the governor will have to work in ranges of 20 to 50 HP or 150 to 300 HP, and I don't know what the torque levels would be either.

I have thought about getting a transmission of some sort from a vehicle, say an automatic or CVT transmission of some type - a manual transmission wouldn't work because I am wanting this to be 'self adjusting' and unattended in nature, or with the minimal attention required. But I don't know if a vehicle transmission would govern the RPM's or not. And if so, how would it do so, or how could it be arranged to do so?

As I said earlier, I also thought about a centrifugal clutch arrangement of some sort. But what would be the best way to do so? And if it were engaged for a period of days I can see the possibility of it burning out, say when the river or creek was in flood stage.

And, with my minimal engineering and mechanical background, I am convinced the possibility I am not finding or thinking of a good solution of some other type might be quite high.

Any help you could give on this problem would be very much appreciated. Thanks, Steve

[JAlberts]

There are many elements to your inquiry and determining a final solution is going to include a bit of a process of investigation and elimination of possible alternatives.
My first recommendation would be to eliminate the idea of a "centrifugal clutch" because these are in application a type of "on-off" rather than speed control device.
As to the possiblity of using a CVT, your best bet is to Goggle "industrial cvt transmission suppliers" where you will find a listing CVT manufacturers and suppliers to contact to learn about the capabilities and limitations of currently available units; and, as a part of this process your are going to have to first determine your maximum desired KW demand level in order to establish the torque and HP your drive assembly must handle. PS, this information is also necessary to determine the minimum size, ie diameter and width of your waterwheel to provide the necessary minimum torque required to provide your desired maximum KW output to your electrical system.

One thing you need to realize is that is pursuing a new type of design project there is always a lot of search and find and learning that is involved; and, today, with the broad range of possible solutions at hand, regardless of whether you are an engineer or not, the best route is to search out and contact those companies that deal in the elements that you are considering. All of these companies have individuals whose job it is to help possible clients determine if and which of their products might be applicable.

[Kelly_Bramble]

I suspect that there is an electronic solution that will allow the motor to run at whatever speed and regulate the voltage and even the amperes.

[JAlberts]

By "motor" I suspect Kelly means "water wheel". I believe, based on current wind turbine applications, she is probably correct and it would be worth your time to investigate those systems' controls. The power sources are different but the operational issues are essentially identical to yours.