Belts and pulleys for WIND TURBINE ?

[BurnIt0017]

Belts and pulleys for WIND TURBINE ?

Hi, I have been working on a Vertical Axis Wind Turbine. The blades I am able to fabricate produce more torque than speed. I am adding a synchronous belt drive transmission. The current configuration is 1 rpm at the input and 7 rpm at the output. I have increased the blade spoke length to aid with start up. Are there any other techniques that I can use to minimize the start up torque needed? Comments welcome.

 

[mrspeedybob]

What are you trying to turn with it? And what sort of wind turbine turns only 1 rpm?

 

[LURCH]

Since it is a wind turbine, I assume he is trying to turn it with wind. Burnit, do you have a disconnect so that the turbine is not trying to drive the generator until it gets up to a certain speed?

 

[BurnIt0017]

Hi, no there is no disconnect. I know I can increase the size of the blades and add length to the blade spokes and that will help. I never studied mechanics and I was wondering if there was any other method that would give a mechanical advantage?

 

[mrspeedybob]

Since it is a wind turbine, I assume he is trying to turn it with wind.

I asked what he was trying to turn with it, not what he was trying to turn it with?

If you are trying to turn a generator then you will probably need a lot more then 7 rpm. For a generator you don't really need a mechanical disconnect because the mechanical load the generator places on the turbine will be in proportion to the electrical load on the generator. You can use an electrical switch mounted on the turbine that is closed by centrifugal force, so there is no load on the generator until the turbine is up to speed. Connect the switch to the external circuit with brushes, like in a DC motor.

 

[BurnIt0017]

Hi, thanks for the suggestions. I was able to exam my PMA and belt drive more closely after the road test and I found that the main shaft was flexing off center as I tighten the timing belts. This allowed the belt to walk over the teeth on the pulley. The more I tighten the belt the more the center shaft was pulled off center. I have to include another bearing above the bottom pulley to prevent the problem. I also believe that the small pulley is to small and not enough teeth on the belt are engaging the pulley. I did find out that my current blade configuration does need to be improve. I purchase some 6 inch pipe and I should be able to configure a C rotor style blade or J shape blade and do another road test in a few days. Thanks again and enjoy the day.

 

[mrspeedybob]

Road test? What in the world are you trying to do with this thing?

 

[BurnIt0017]

Hi, the only way I have to test the unit is to mount it on the back of my car and than I drive down the road at different speeds and measure the output using a 12 volt battery for a test load. I did find a bearing that I can use to solve the biggest problem of the shaft being pulled off center. It will be a few days to fabricate the housing. Thanks again and enjoy the day.