Help w aux setup for homemade voltage clamp

[weisea]

Thanks for the spreadsheet Max.  I'm sure it will help creating a turbine profile.

Andy

[keyturbocars]

Max (or others):

Since I didn't build my wind turbine, I am not sure what the best values to enter for these parameters. Can someone explain these.  I recognize TSR, but I do not know what value to enter for my turbine.  The other 3 parameters I am not sure what they mean.

% prop
TSR
R betw. 2 Ph.
U/RPM  DC

Thanks,

Edward

[keyturbocars]

I did some more studying and I have used the following data for my HY-2000 wind turbine:

% prop = 40%  (assuming a Cp of 0.4 for blade efficiency)
TSR = 7.30 (based on data I had from the manufacturer)
R betw. 2 Ph. = 0.66 (not exactly sure what this is, but I assumed it'd be standard for 3 phase alts)
U/RPM  DC = 0.17 (volts/rpm - I was able to get this one from actual factory data on my turbine)

I have created a new wind curve in my Classic based on the data generated by the Excel spreadsheet, and I will see how it works the next time the wind blows. 

Thanks again Max for the helpful (and fun) spreadsheet to experiment with!

Edward

[weisea]

Edward,

I will be keeping an eye out for the results you get from using Max's spreadsheet for your Classic wind curve. 

I believe the "R betw. 2 ph" is the line to line resistance of the alternator.  Max uses this to calculate the (U Loaded AC) loaded voltage out and the electrical efficiency of the alternator.
If the results of your efficiency is off you could adjust this number up or down to get closer to your measured numbers.  The same is true for the loaded alternator voltage.  Make the number smaller to increase the voltage and larger to lower the calculated voltage on the spreadsheet.

Max, correct me if I have missed the point and thanks again for your work.

Good luck with the wind curve Edward I will be following you with my own in the near future.

Andy

[keyturbocars]

Thanks for the information Andy. 

My wind turbine is shut down for now while I have my Classic worked on by Midnite.  Last night, I accidently uncovered a situation where the input voltage can climb too high.  No problem, boB and Ryan immediately responded and talked with me on the phone extensively to troubleshoot what happened. Midnite is going to repair my Classic ASAP and get me up and running again.  Great customer service! 

I'll have to comment on the new wind curve results after I get my Classic back.

Edward

[boB]

Thanks for the good service kudos, Edward, but that problem shouldn't have occurred in the first place.

Remember to NOT let the step 01 and step 02 Amps be the same until I fix that in software so
that it can't happen even if you do try to.  Also the other steps, just in case they can present
a similar problem and leave step 01 cutin Amps at 0 as well.

boB

[keyturbocars]

Thanks for the good service kudos, Edward, but that problem shouldn't have occurred in the first place.

boB, With a product as complicated and sophisticated as the Classic, I think it's very understandable that some of these things would not surface during initial product testing.  Besides, you never can tell what a crazy end user might do at 1AM in the morning with a hyperactive index finger punching the keys too fast in wind editor mode!   

The Classic is a great product and it will only get better over time as some of these details come to the surface and are worked out.  In the meanwhile (before the software is updated), I'll try to slow down my hyperactive index finger and be careful not to let the AMP setting between 2 step points be equal! 

Edward

[Menelos]

Hi There,

Weisea is right,

R betw. 2 Ph. means the resistance you measure between 2 oft the 3 Phases of your alternator. This is a critical number. The higher the restistance of the alternator, the higher the internal voltage drop inside the alternator and thus the lower the loaded voltage which is what we need for the power curve.
You can find out about that by taking a multimeter and measure the resistance between 2 Phases.

I believe the curves created with my tool will, for most turbines, be good to start with. But still, perfomance can be increased for each individual turbine by playing around with the numbers a little, depending on the airfoil used and especially also depending on the location of the turbine. In verry gusty areas for example, I would alsways have the prop run a liitle above design TSR to better pick up gusts...

This isn' an exact science :-D

Anyway, for my aeocon inverter it works fine :-)

Max

[keyturbocars]

Thanks for clarifying Max.  I will measure the resistance between 2 phases on my turbine.

Edward

[keyturbocars]

When trying to measure the resistance between 2 phases of my wind turbine alternator, the readings kept bouncing around all over the place.  The turbine was not spinning.  I have an older Fluke digital mulitimeter and I set it to the 200 Ohm range.  The numbers kept changing so much that I could not get a useful reading of the resistance. 

Could this be because the resistance is so low that this multimeter is unable to measure it accurately?

Edward

[weisea]

I think you are right...the resistance is too low and also there may be noise pick up on the meter.

Set up a battery and a series resistor to put at least 1 Amp of dc current through the 2 phases of the alternator winding.  Measure the voltage drop across the 2 phases and divide by the measured current to get resistance.  The Fluke should be able to give a fairly accurate result. 

Andy

[keyturbocars]

Thanks for the idea, Andy.

- Edward

[Menelos]

I do not think that the resistance is to low for the multimeter to detect ist. If it was so, it would just show zero. Anyway, depending on the size of your turbine it should be something between 0,3 and 2 Ohms...

Try another multimeter and make sure, the turbine is not moving at all.

Max

[len]

Hi,
     I dont know if anybody else has tried this, but I use three surge resistors in series with the AC output of the turbine so when you short the turbine it protects the windings, without the resistors my turbine would rattle when shorted, but its nice and smooth now. The only issue is getting the correct value surge resistor. I also have a timer devise (3mins or so) which lets the reistors cool down between the shorting out periods

[keyturbocars]

Len, I also use resistors, but I have it wired so that I can first load down the turbine with resistors before shorting out the 3 phases.  Sounds like you might have yours wired with the resistors in series with your shorting breaker.  I do it in stages.  First load down the turbine with resistors to slow it for a little while, and then flip a breaker that shorts out the 3 phases.