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Author Topic: Reactive power - Reactive Generator research from GotoLuc - discussion thread  (Read 362026 times)

gotoluc

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Luc
In regards to your last video-something seems not right. Are your DMM's reading rms voltage?. The reason i ask is this.
The prime mover uses 157-158 watt's-with or with out the reactive circuit switched on.
Without the reactive circuit switched on,your exciter circuit meters read this- 167.2volts @ 1.405 amp's. This is 234.916 watt's ??? -asumeing a power factor of 1.

Yes, they are true RMS if the sine wave is clean!... I was just showing you what mine did the way you did so you could see the difference.

As far as explaining... your asking the wrong guy.

Luc

gotoluc

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According to the manual, you have the following image file format options to save to:

bmp, pcx, tiff, rle, epsimage, jpeg

I would suggest trying tiff and jpeg. I don't see where one can change the resolution though.

btw, nice scope Luc. Where did you buy it?

Okay, I'll look into it. What if I connect it directly to my computer through USB is there an application for it?

The Scope is a loaner from Thane Heins

Luc

gotoluc

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Luc, isn't your watt meter plugged into the output of your generator?

Never mind. I see that it is plugged into the AC feed to the genset, which is feeding your motor.

No!... it's connected across the gen exciter coil and cap.

Luc

gotoluc

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I see, thanks.

So the gen exciter circuit requires about 60W. I wonder if that 60W increases as the gen is loaded?

As soon as you add a resistive load the power to prime mover goes up in the standard way. 10 watts out takes about 11watts in
Only the reactive circuit if tuned correct will have no effect but seems to have a limit of around 35 watts output.

So once you start drawing more than 30W from the gen, the motor power indicated on the meter starts to increase as well, and under 30W the motor power remains at a relatively steady 158W?

Yes, but I can make it go the other way also. Less watts to the load and drop the 158 watts to 120 watts if tuned that way. TinMan demonstrated this in his video.

Luc

gotoluc

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Okay, here is a video demo of the circuit I was getting 90 watts out for an apparently smaller amount in.

Link to video: http://www.youtube.com/watch?v=nr2-qIX9G3U&feature=youtu.be

I'm off for a visit to my girl friend so won't be able to do anything more till Monday some time. I'll have my laptop and may answer questions.

Luc

poynt99

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Okay, I'll look into it. What if I connect it directly to my computer through USB is there an application for it?

The Scope is a loaner from Thane Heins

Luc
Yes, you can connect the scope directly to your PC through the rear USB port, but you will need to install the software in order for the scope to be recognized (drivers) and to port over the images. I'm not sure if Tektronix has the software freely downloadable from their website, but I will check.

That was nice of Thane to do that. You must be one of only a few people that are in his good books.

ETA:

OK, I found the free software. It is called "Openchoice Desktop Application"
http://www.tek.com/oscilloscope/tds210-software/openchoice-desktop-application-tdspcs1-v23-0
You need to log in to download it. I am downloading now. It is 414MB. How may I get this to you?

poynt99

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No!... it's connected across the gen exciter coil and cap.

Luc
I meant the Watt meter that is plugged in to your generator, not your DMM meters.

poynt99

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Okay, here is a video demo of the circuit I was getting 90 watts out for an apparently smaller amount in.

Link to video: http://www.youtube.com/watch?v=nr2-qIX9G3U&feature=youtu.be
Thank you Luc. You answered my question. For your other tests where you had a negative MEAN and CH2 was inverted, did the MEAN value also change when you went to non-inverted? By change, I don't just mean from negative to positive, but did the actual value change too like it did in this video?

This gives me something now I can investigate.

btw, the MEAN value amplitude should be the same (to the best of my knowledge) when changing from inverted to non-inverted, so something strange may be happening there.  ???

poynt99

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OK Luc,

I've figured out a big part of the puzzle.

Thank you for showing the channel settings on your scope. When I changed the coupling on both channels to "AC" on my scope, I got the negative MEAN value. I of course have been using "DC" coupling, and you need to also.

The reason that we can't use AC coupling is because doing so inserts a capacitor in series with the probe input. The capacitor is not large enough in value to pass 60Hz without altering it, and it is this alteration (change in wave shape) that is causing your negative MEAN value.

Even if I only change the CH2 probe back and forth from AC to DC coupling, the MEAN value will change from +2.5W to -2.5W. You can see a slight change in the CH2 wave form shape when changing back and forth.

See the attached for a bit of info. With square waves, you can see how much it changes the wave shape, even at 80Hz. We are not using square waves, but the CSR wave form does contain many higher frequencies than 60Hz.

Try changing both channels to "DC" coupling. I think you might see a significant difference in your results.

Now, I still have to figure out why your scope is not displaying the same MEAN value regardless if CH2 is inverted or not (only the polarity should change). They should be the same, and I have confirmed this again with my measurement. The fact that yours changes tells me that there is some sort of offset somewhere that is causing an imbalance so to speak.

gotoluc

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OK, I found the free software. It is called "Openchoice Desktop Application"
http://www.tek.com/oscilloscope/tds210-software/openchoice-desktop-application-tdspcs1-v23-0
You need to log in to download it. I am downloading now. It is 414MB. How may I get this to you?

Would it not be just as easy for me to download it then for you to upload it to a fileshare place?

So not sure what to answer on this one.

Luc

gotoluc

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Luc, isn't your watt meter plugged into the output of your generator?

Never mind. I see that it is plugged into the AC feed to the genset, which is feeding your motor.

I meant the Watt meter that is plugged in to your generator, not your DMM meters.

Okay, I now understand!... I modified the gen panel plugs, one is connected to grid (with plug in watt meter) and the other plug is the gen output.

Luc

poynt99

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Would it not be just as easy for me to download it then for you to upload it to a fileshare place?

So not sure what to answer on this one.

Luc
Sure.

You'll have to register with them. Your choice.

gotoluc

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OK Luc,

I've figured out a big part of the puzzle.

Thank you for showing the channel settings on your scope. When I changed the coupling on both channels to "AC" on my scope, I got the negative MEAN value. I of course have been using "DC" coupling, and you need to also.

The reason that we can't use AC coupling is because doing so inserts a capacitor in series with the probe input. The capacitor is not large enough in value to pass 60Hz without altering it, and it is this alteration (change in wave shape) that is causing your negative MEAN value.

Even if I only change the CH2 probe back and forth from AC to DC coupling, the MEAN value will change from +2.5W to -2.5W. You can see a slight change in the CH2 wave form shape when changing back and forth.

See the attached for a bit of info. With square waves, you can see how much it changes the wave shape, even at 80Hz. We are not using square waves, but the CSR wave form does contain many higher frequencies than 60Hz.

Try changing both channels to "DC" coupling. I think you might see a significant difference in your results.

Now, I still have to figure out why your scope is not displaying the same MEAN value regardless if CH2 is inverted or not (only the polarity should change). They should be the same, and I have confirmed this again with my measurement. The fact that yours changes tells me that there is some sort of offset somewhere that is causing an imbalance so to speak.

Okay, something new learned!... DC coupling when wanting accurate math results from an AC source.
Not a problem. I will do that from tomorrow on.

Thanks for finding that one.

Luc

gotoluc

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Sure.

You'll have to register with them. Your choice.

Well, if you're ready to upload it to some file share then I'll take you up on the offer. It would be easier then to register and all.

Thanks for your help.

Luc

poynt99

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Okay, something new learned!... DC coupling when wanting accurate math results from an AC source.
Not a problem. I will do that from tomorrow on.

Thanks for finding that one.

Luc
You're welcome.

I had another gander at the CH2 wave form while changing from AC to DC coupling, and not only does the wave shape change a little, the phase shifts a little too.