Language:
To browser these website, it's necessary to store cookies on your computer.
The cookies contain no personal information, they are required for program control.
the storage of cookies while browsing this website, on Login and Register.

### GDPR and DSGVO law

Storing Cookies (See : http://ec.europa.eu/ipg/basics/legal/cookies/index_en.htm ) help us to bring you our services at overunity.com . If you use this website and our services you declare yourself okay with using cookies .More Infos here:
https://overunity.com/5553/privacy-policy/
If you do not agree with storing cookies, please LEAVE this website now. From the 25th of May 2018, every existing user has to accept the GDPR agreement at first login. If a user is unwilling to accept the GDPR, he should email us and request to erase his account. Many thanks for your understanding

Custom Search

### Author Topic: Reactive Generator Research for everyone to share  (Read 130677 times)

#### hartiberlin

• Hero Member
• Posts: 8012
##### Re: Reactive Generator Research for everyone to share
« Reply #105 on: December 05, 2013, 02:13:13 AM »
I think the 137 Watts input I was calculating was wrong, cause I just multiplied
both the Red MATH Voltage and red MATH Current Values in this scope shot;

http://www.overunity.com/14013/reactive-generator-research-for-everyone-to-share/dlattach/attach/129865/

But you can see here in this scopeshot, when you loook at the red Math sine curve, that its highest peak value
is about 306 Watts of positive input power and Minus 187 Watts of returned input power at its lowest value.

Not knowing, what the scope values in there in this Math function for factors,
I can not really say, if the Root Mean Square difference of these 2 values
is really 49 Watts, what the digital Kill-a-Watt type Meter had displayed, or if it is more...
Maybe if we calculate:

306 Watts peak input power / 1.41 = 217 Watts RMS input power

-187 Watt Peak Power returned / 1.41 = - 132 Watts RMS Returned power

(1.41 is the "squareroot of 2" factor for the RMS value)

So the difference is 85 Watts of total RMS input power.

But your Kill-a-Watt type digital Watt Meter just showed 49 Watts of REAL input power, so the Reactive Input power
must be the difference, so 36 Watts of Reactive Input power.

I hope this helps , or maybe I am totally confused and wrong ??

Regards, Stefan.

#### gotoluc

• Moderator
• Hero Member
• Posts: 3096
##### Re: Reactive Generator Research for everyone to share
« Reply #106 on: December 05, 2013, 03:43:56 AM »
Hi Luc, well,
as it is an AC motor surely it is inductive to the grid and has a power factor which is not 1.
So please also show exactly the change in power factor at this drive motor,
when you apply the load at the generator output.

Please also put a incandescent lamp in series with the drive motor, so we can see, if this bulb
changes its brightness, when you draw power from the generator.

You really have to exactly look at the input of the drive motor, what is going on...

Regards, Stefan.

All this was checked before.

When generator prime mover is connected to grid with scope probes attached to it with CSR to measure current, voltage and phase,  there is zero change to all when circuit is connected or disconnected to generator.

You may of missed the part where I wrote I was working with Gyula on this for about a month before releasing the information to see if I could be missing something. Gyula could not find anything and was very surprised to see it had no effect on the generator prime mover.

I am now done with the questions and won't be wasting my time to prove this or that. It is so simple to build since I gave all that is needed, so build it for yourself to prove or disprove what ever you want.

Luc

#### hartiberlin

• Hero Member
• Posts: 8012
##### Re: Reactive Generator Research for everyone to share
« Reply #107 on: December 05, 2013, 05:17:28 AM »
Hi Luc,
thanks for the additional info.

I am stuck in some software work and private preparations etc...
but I have got a new digital scope and will next year try to replicate it when I find the
time.
Looks like a simple experiment with just the MOT transformers first...

Would be interesting to see, if with bigger transformers you could extract more and more power
by using less input power this way...

Regards, Stefan.

#### gotoluc

• Moderator
• Hero Member
• Posts: 3096
##### Re: Reactive Generator Research for everyone to share
« Reply #108 on: December 05, 2013, 05:52:17 AM »
Great Stefan,

I'm glad you see that a simple replication is the best way to understand the effect.

All the best to you in this Holiday Season and may you have success with this circuit in the New Year

Regards

Luc

#### hartiberlin

• Hero Member
• Posts: 8012
##### Re: Reactive Generator Research for everyone to share
« Reply #109 on: December 05, 2013, 01:44:04 PM »
Okay, Luc,
but if you or anybody else is doing this test again,
please also show us the power feactor on your grid Kill-a-Watt Wattmeter during all
measurement steps, so that we can see, if the power factor does change at the input.

Many thanks in advance and also have a nice Christmas season !

Regards, Stefan.

#### tim123

• Hero Member
• Posts: 509
##### Re: Reactive Generator Research for everyone to share
« Reply #110 on: December 05, 2013, 07:33:48 PM »
Hi Luc,
I've done some tests, but I'm not sure my results match yours... Please see attached schematic...

- Can you tell me if the layout I'm using is right? Do I have the scope probes in the same places?
- I'm using A-B for the math function...

Basic Findings:

- At low capacitance, the 2 channels are out of phase
- With enough capacitance, the 2 channels go into phase
- Then adding extra caps - makes no difference.

- Power factor, and wattage goes up as phases converge
- Power thru the load (bulb) goes up as phases converge

It all looks pretty linear to me: When out of phase, less power usage is shown, but the bulb is less bright too (or off)... As the capacitance increases, the phases converge, power factor goes up, bulb gets brighter.

Some Details:

- My variac uses about 10w on minimum.
- In tests below, my standard for a 'lit' bulb - is where just one particular part of the filament turns red.
- I used a separate DMM to measure AC voltage across the bulb.
- Power factor shown by the meter varied between 0.5 and 0.9
- Power factor generally increases as the voltage goes up.

Without Reactive Circuit:
- Bulb connected directly to variac - lights with 19.5v AC
- Wattmeter says 12.9W

With Reactive Circuit:
- Bulb lights with 20v
- Wattmeter says 12.6W
- Note - I can increase the voltage from the variac to any amount, reduce the capacitance accordingly, and end up with the same voltage across the bulb, and (more or less) the same wattage shown on the meter. It varies between 12.3 and 13 W.

Do you have any comments or advice?

Regards
Tim

#### gotoluc

• Moderator
• Hero Member
• Posts: 3096
##### Re: Reactive Generator Research for everyone to share
« Reply #111 on: December 05, 2013, 09:12:57 PM »
Hi Tim,

so it looks like you are on 220vac grid?

What are you doing with the MOT Secondary?

Luc

EDITED

I modified your diagram and added instructions

#### tim123

• Hero Member
• Posts: 509
##### Re: Reactive Generator Research for everyone to share
« Reply #112 on: December 05, 2013, 10:46:05 PM »
Hi Luc,
the secondary was already shorted (said so in diagram).

I don't understand what the difference would be to use another resistor in series with the bulb...? It's a resistor itself... (In which case the probes you drew are in the same place as mine - so I did get that right then...)

Regards
Tim

#### gotoluc

• Moderator
• Hero Member
• Posts: 3096
##### Re: Reactive Generator Research for everyone to share
« Reply #113 on: December 05, 2013, 11:24:18 PM »
Hi Luc,
the secondary was already shorted (said so in diagram).

I don't understand what the difference would be to use another resistor in series with the bulb...? It's a resistor itself... (In which case the probes you drew are in the same place as mine - so I did get that right then...)

Regards
Tim

Hi Tim,

yes, I now see the Secondary says shorted!

A current measuring Resistor needs to be separate from the load and placed after it on the return Neutral side. It can be of a small value like 0.1 Ohm or even smaller when large loads are used, but the smaller the value the more precise its value needs to be to get good power calculations. You cannot use a light bulb as a Resistor to do any power calculation since its Resistance changes as it is being lit.

Make sure your probe Grounds are always together and on the Neutral side of the grid or you can fry your scope as they are usually common ground and grounded though the Grid ground. So you can imagine what would happen if you introduce them on the hot side... POOF!

Have fun

Luc

#### tim123

• Hero Member
• Posts: 509
##### Re: Reactive Generator Research for everyone to share
« Reply #114 on: December 06, 2013, 11:45:16 AM »
I've attached an image of my test bench - just for info...

Luc, I'm not sure what I should be looking for...

The capacitors don't seem to 'tune' anything - as I said - you just need 'enough' (for me, about 30uF) to correct the power factor, and any extra makes no difference.

Using less than enough (less than 30uF) - and the phases diverge. With about 5uF or less they're 90 degrees out. At this point there's very little power being delivered to the load, but my variac still draws some power (10-12w).

For my 13w in (to 'light' the bulb - one part of filament goes dull red), I get about 20v across the 50ohm bulb. (I know a bulb's resistance changes when it gets hot - but I'm not letting it get very hot.) I'm not sure if my DMM reads peak, or RMS, but either way the output power is 9watts or less. (8.8 if RMS, 6.3 if peak, I think)

So, with any amount of caps, it looks clear that I'm getting less out than I'm putting in.

So, questions:

1) Do you have a cap switch box - so you can change values while the circuit is running? If not - how do you do it?

2) Have you found that the phase is 90 deg out with very low capacitance, and converges as capacitance increases, to a plateau?
i.e. Do your results concur with mine?

3) It seems to me that a resistive load *requires* the phases to be together... I think the very definition of resistance means that the power has to be 'used up' (converted to heat). It's possible that an inductive load would be different. What do you think?

Regards
Tim

#### tim123

• Hero Member
• Posts: 509
##### Re: Reactive Generator Research for everyone to share
« Reply #115 on: December 06, 2013, 11:52:59 AM »
Close up pics of the cap switchbox, FYI...

#### Farmhand

• Hero Member
• Posts: 1583
##### Re: Reactive Generator Research for everyone to share
« Reply #116 on: December 06, 2013, 04:01:51 PM »
Hi Tim, Maybe I can help.  I use Two MOT's in parallel in the power supply of my Tesla coil, They measure about 236 mH each, but when in series they are of course double that. I'm on 240 volt grid as well. During the day with the solar array feeding the grid the voltage rises to over 260 volts.

A 240 volt MOT as compared to a 115 volt MOT would have a fair bit more inductance and so requires less capacitance to get resonance i think. But the lower frequency of 50 Hz means we need a bit more C than those on 60 Hz kind of thing.

For mine I require almost 38 to 40 uF across the MOT's in parallel but I forget how much when in series.

The reason I put the capacitors across the MOT's and tune them to near resonance is that it makes the voltage drop less and the output more, it also improves the power factor (PFC).
I get up to 0.97 power factor on the supply to my spark gap Tesla coil, it varies with the energy used.

I'm not sure what exactly Luc tunes for, but my guess is the MOT's the caps and the motor make the circuit L/C way past resonance.

L/C resonance calculator.
http://www3.telus.net/chemelec/Calculators/LC-Calculator.htm

We must not forget that with 240 volts and so much capacitance these setups are extremely dangerous and definitely can be lethal. I employ line filters on the supply to the MOT's, they have a parallel resistor in them that bleeds the charge off the caps. 240 volts should pump twice the current through a body as would 120 volts. Risk is increased.

Cheers

#### tim123

• Hero Member
• Posts: 509
##### Re: Reactive Generator Research for everyone to share
« Reply #117 on: December 06, 2013, 06:37:33 PM »
Hi Farmhand,
your Tesla coil sounds like a beast. I'd like to see it running.

I'm finding this all very interesting and informative. I've learned a lot already, and I'm grateful to Luc for bringing this up. I never really 'got' power factor, and now I can see it on the scope - and on my wattmeter...

I think this LC resonance calculator is better:
http://www.1728.org/resfreq.htm

My MOT primary is 292mH, so a capacitance of about 35uF should give a resonant frequency of 50Hz. However, I had the secondary shorted - which made it exactly 50mH, (so a capacitance of about 202uF should give a resonant frequency of 50Hz.). Luc, can you measure yours?

I will have a play again later/tomorrow and see if I can observe the resonance... I think I need to try capacitance / load on the 2ndary too - and see what that does.

Regards
Tim

#### tim123

• Hero Member
• Posts: 509
##### Re: Reactive Generator Research for everyone to share
« Reply #118 on: December 06, 2013, 07:58:22 PM »
Update: I put a 1uF cap across the MOT secondary, and the bulb lit at 12.3w - i.e. better than without the reactive circuit. I tried a range of caps up to 100uF, but it didn't seem to make any difference after the initial 1uF.

I tried another 100w bulb on the secondary as a load. It didn't light, but the main bulb lit again at 12.3w - so it does help.

Both together in series or parallel - still 12.3w.

It looks like the circuit is doing a fairly good job of correcting the power factor from the variac...

#### hartiberlin

• Hero Member
• Posts: 8012
##### Re: Reactive Generator Research for everyone to share
« Reply #119 on: December 07, 2013, 12:43:49 AM »
Hi Tim,
well done.
Maybe oyu can also try to measure voltage and current BEFORE the Variac with your scope.

Be sure to not short out the gridÂ´s hot pole, so put the current shunt into the ground pole
and not in the hot pole side !

Please post scopeshots or a Youtube video where you show this if you can.

Many thanks in advance.

Can you already verify that the power factor does not change at the input when you load the output ?

What pahse angles do you get between current and voltage ?
Are you on a 230 Volts 50 Hz system or 60 Hz 120 Volts system ?

Regards, Stefan.