100W capacitive wireless power transfer with Tesla coil

[BSpg]

Hi, I'm interested in wireless power transmission using Tesla coils.This is a near-field region.
I think a good understanding of the phenomenon in the near-field region is very important for further understanding of Tesla's work.

For the future experiments, I used a very simple oscillator with a Tesla coil (Slayer Exciter).

With this configuration and with a relatively small Tesla coil, I have achieved very interesting results
- wireless power transmission 60W at 90cm distance or 100W at 70 cm distance.

It is surprising, that the power is transferred mainly by capacitive coupling.
Inductive coupling is in this case negligible.

One part of the mutual capacitance makes top load and the other part is the surface of the coil that operates the same as the capacity.

For longer distances, it is obvious capacitive power transmission more efficient than inductive power transmission.

Configuration with two coils and ground connection:


Configuration with three coils without ground connection:





It is interesting that this configuration is somewhat similar to Tesla’s version of wireless energy transmission shown in this picture:




Something more about it on my blog:
SpigelLab

and video:
https://www.youtube.com/watch?v=CbqR8EpIP04

[Ernst]

I am assuming that you think "if I can light a 60W bulb, I have 60W of power"
This is not true, not by a long shot.
The way you'd normally light a 60W bulb, you'll get perhaps 5W of light and 55W of heat.
By using HF currents you can significantly better this performance. With HF short pulses you can light the bulb while it remains entirely cold, spending perhaps 6-7 Watt.

You have a SEC with 2 oscillators? Is that "the extended version"?
My SEC has only a resistor, a transistor and a couple of diodes (and a primary and secondary winding, of course).

I think you give a whole new meaning to that diagram of the "rare notes".
My interpretation and that of some others that I know of (Gary Peterson for example) is completely different.

You have a nice lab!

(around 1.48 in that video you show that you have a 1/4 wave resonance in your coil)

Good luck in your studies.


Ernst.

[BSpg]

I am assuming that you think "if I can light a 60W bulb, I have 60W of power"
This is not true, not by a long shot.
The way you'd normally light a 60W bulb, you'll get perhaps 5W of light and 55W of heat.
By using HF currents you can significantly better this performance. With HF short pulses you can light the bulb while it remains entirely cold, spending perhaps 6-7 Watt.

Hello Ernst,

I do not know whether you thought that 60W incandescent bulbs powered with short pulses, can normally light with 6-7W?
This would be an excellent energy efficiency - responds LEDs.

I would be glad if you could show me some links regarding measurements and comparisons, because unfortunately something that I could not find.

Small correction - the lamp is operated by a sinusoidal signal frequency 700 kHz (not-pulse).
After several minutes, the lamp will be very hot - obviously increased the amount of heat energy is consumed.
Generally light bulbs is ohmic resistance.

I've been to your threads and I like the topics.

Scheme and other details you can see:
100W Wireless and Single-Wire Power Transmission with High Power Double Slayer Exciter – SpigelLab

Here are two videos that I have not mentioned before:
https://www.youtube.com/watch?v=ARCLD3qgjmI
https://www.youtube.com/watch?v=Dc6Cw4GomMY

Good luck,

[BroMikey]

Hi BSpg

This is a good experiment. You show everything on the
power out, maybe 100W? How many watts is your input
for your double slayer?

Just a general idea, say 20w input and 100watts out?

Thanks in advance

[Sputins]

Scheme and other details you can see:
100W Wireless and Single-Wire Power Transmission with High Power Double Slayer Exciter – SpigelLab

Here are two videos that I have not mentioned before:
https://www.youtube.com/watch?v=ARCLD3qgjmI
https://www.youtube.com/watch?v=Dc6Cw4GomMY

Good luck,

Hi Spigel.

Nice set up you have there.

So the neutral terminal of the L1 secondary coil drives the base of T1 & T2 (2SC5200) which sets up the oscillation. But you don’t have much control over the driving frequency. (Granted, it self regulates and is conveniently simple). - You could try a signal generator (and small amp) to drive the base of the T1 & T2 instead, giving you some more flexibility with the tuning frequency and free's up the neutral terminal of L1.

If you had independent frequency control, I wonder if you’ll have similar result if you removed L1 secondary all together. Maybe simply Lp1 & Lp2 alone would give a similar result via loose coupling to L2?

Anyway it’s good to see your experiments.

[Ernst]

Hello Ernst,

I do not know whether you thought that 60W incandescent bulbs powered with short pulses, can normally light with 6-7W?
This would be an excellent energy efficiency - responds LEDs.

I would be glad if you could show me some links regarding measurements and comparisons, because unfortunately something that I could not find.

Small correction - the lamp is operated by a sinusoidal signal frequency 700 kHz (not-pulse).
After several minutes, the lamp will be very hot - obviously increased the amount of heat energy is consumed.
Generally light bulbs is ohmic resistance.

I've been to your threads and I like the topics.

Scheme and other details you can see:
100W Wireless and Single-Wire Power Transmission with High Power Double Slayer Exciter – SpigelLab

Here are two videos that I have not mentioned before:
https://www.youtube.com/watch?v=ARCLD3qgjmI
https://www.youtube.com/watch?v=Dc6Cw4GomMY

Good luck,

I'll have a look at these links later. I read that you use the 2SC5200 for your SEC. That is the same one I am using. It is a very good transistor to build a HV SEC (normally a SEC does not give a very high voltage).
I don't have links for you on power measurment but you can do it very easily by yourself.
1 - add a small (1-5 Ohm) resistor in series with the bulb and measure the voltage across it. Use this to calculate the current: I = V / R
2 - measure the voltage across the bulb
3 - power consumed by the bulb: P = I V
Do it, you'll be surprised!

You will find infomation on why this method is more efficient in Tesla's lectures of 1891-1893.

I understand that you are using a sinusoid power supply, I only mentioned the pulsed mode as an example to further increase the efficiency. Search this forum for 'cold electricity' and you'll find more on that subject.

Enjoy these fascinating experiments! (entirely needless to say, I guess)

Ernst.

[BSpg]

Hi, BroMikey

[SIZE="3"]
Just a general idea, say 20w input and 100watts out?

Great idea, but ....

For your question, I can not give unambiguous answer.
There are a lot of parameters that need to be studied in depth:

- distance L1 and L2 - power is not linear with the distance - less distance may not be at the same time a stronger signal
- incandescent bulbs (40W, 60W, 100W)
- power supply (150W or something a bit more) - there are current and voltage protection, which limits the power.

The basic thing I can say - this is not overunity device, but some elements are strange.

For example- if the coil L2 is not near the device (distance beyond 2m), the device consumes maximum power, which allows him power supply (about 180W).
I think that the device consumes power on the wave radiation - I'm not entirely sure.

When the coil L2 approaches (when it comes to capacitive coupling) power consumption drops sharply.
With 60W incandescent bulb, consumption is usually between 80W - 120W depends on the distance. It is possible that a portion of this energy is spent on radio radiation.

Thanks,
BSpg

[Ernst]

A Tesla coil produces a myriad of effects in the surrounding medium.I will be doing a video on that soon, in fact I have just started on it. I think that the "longitudinal waves of electrified air", as Tesla calls them, are attributing to the "power anomalies" that you are seeing.

It goes roughly like this: when the top-load is charged positively it repels + ions and attracts - ions. When it is charged negatively it is the other way round. This rythmical attraction and repulsion causes a longitudinal wave, in the coils vicinity. This also uses energey and slows the natural vibration of the coil down. The higher the voltage the more pronounced this effect.

When there is another coil in the neighbourhood with the same resonance frequency this second coil will resonate in a 180 deg phase shift. When the powered coil repels charge the other coil attracts the same, so it helps the first coil and it focusses the radiated energy.
You can make this visible by puting fluorescent lights around at a distance so they just light up. Then when you bring in the second coil the lights will go out, except those between the coils.

Lots of stuff to try and play with, but no overunity. I think that will be very difficult to achieve with a SEC.


Ernst.

[Ernst]

So many people say Tesla said this, that or the other, and then often refer to something he never said. I too found that sometimes what I think to remember is an interpretation of the actual text.
So.... where does Tesla mention longitudinal waves of electrified air?

1892-12-21: On the Dissipation of Electrical Energy of the Hertz Resonator

The apparatus, oscillator and resonator, being immersed in air, or other discontinuous medium, there occurs—as I have pointed out in the description of my recent experiments before the English and French scientific societies —dissipation of energy by what I think might be appropriately called electric sound waves or sound-waves of electrified air.

Read the whole article, it is very relevant to these experiments.


Ernst.

[Solarlab]

Hello Ernst,

I do not know whether you thought that 60W incandescent bulbs powered with short pulses, can normally light with 6-7W?
This would be an excellent energy efficiency - responds LEDs.

I would be glad if you could show me some links regarding measurements and comparisons, because unfortunately something that I could not find.

Small correction - the lamp is operated by a sinusoidal signal frequency 700 kHz (not-pulse).
After several minutes, the lamp will be very hot - obviously increased the amount of heat energy is consumed.
Generally light bulbs is ohmic resistance.

I've been to your threads and I like the topics.

Scheme and other details you can see:
100W Wireless and Single-Wire Power Transmission with High Power Double Slayer Exciter – SpigelLab

Here are two videos that I have not mentioned before:
https://www.youtube.com/watch?v=ARCLD3qgjmI
https://www.youtube.com/watch?v=Dc6Cw4GomMY

Good luck,

Your "Basic Tesla's Experiments (Part 1) - 100W Wireless Transmission without Ground Connection" I find quite enlightening and very interesting. Sparks a whole variety of practical application ideas!

Curious - since you have three (3) coils; have you tried one (1) TX with two (2) independent RX?

Thanks, great work backed by very good presentations...

[BSpg]

Hi Sputins

Very thanks for your support.

So the neutral terminal of the L1 secondary coil drives the base of T1 & T2 (2SC5200) which sets up the oscillation. But you don’t have much control over the driving frequency. (Granted, it self regulates and is conveniently simple). - You could try a signal generator (and small amp) to drive the base of the T1 & T2 instead, giving you some more flexibility with the tuning frequency and free's up the neutral terminal of L1.

Your idea with independent frequency control it seems just fine.
Fits if it does not change the distance between the coils L1 and L2.
It is then possible to examine the frequency of the maximum transmission power.

In the current configuration, the frequency is automatically generated.
When changing the distance between L1 and L2, at the same time is changed and the mutual capacitance
which affects the resonant frequency of the coil L1.

At greater distances mutual inductance is very small (and for reasons of parallel position L1 and L2).

Here is a diagram of the frequency change in relation to the distance between the coils:

If you had independent frequency control, I wonder if you’ll have similar result if you removed L1 secondary all together. Maybe simply Lp1 & Lp2 alone would give a similar result via loose coupling to L2?

L1 resonates and generates high voltages. Coupling between the two coils (L1 and L2) is primarily by electric field (Resonant Capacitive Coupling - electrostatic induction).

High voltages and Resonant Capacitive Coupling enables efficient power transmission between L1 and L2.
Without L1 it would not be possible. In any case, I plan to try.


Spigel

[BSpg]

Hi Ernst,
Thanks for response and support.

I don't have links for you on power measurment but you can do it very easily by yourself.
1 - add a small (1-5 Ohm) resistor in series with the bulb and measure the voltage across it. Use this to calculate the current: I = V / R
2 - measure the voltage across the bulb
3 - power consumed by the bulb: P = I V

SEC generates high voltages and high frequencies (in my example 700kHz) - ?

Measuring voltage/current at high frequency - diyAudio

BSpg

[BSpg]

Hi Ernst

A Tesla coil produces a myriad of effects in the surrounding medium.I will be doing a video on that soon, in fact I have just started on it. I think that the "longitudinal waves of electrified air", as Tesla calls them, are attributing to the "power anomalies" that you are seeing.

It goes roughly like this: when the top-load is charged positively it repels + ions and attracts - ions. When it is charged negatively it is the other way round. This rythmical attraction and repulsion causes a longitudinal wave, in the coils vicinity. This also uses energey and slows the natural vibration of the coil down. The higher the voltage the more pronounced this effect.

This explanation seems interesting and it is possible that the interaction of the ions, one of the main reasons for the loss of energy (when the coil L2 is not near the coil L1). Another cause is certainly a radio wave that radiates L1 (this is easily measurable).

Thanks

BSpg

[Ernst]

Hi Ernst,
Thanks for response and support.

SEC generates high voltages and high frequencies (in my example 700kHz) - ?

Measuring voltage/current at high frequency - diyAudio

BSpg

You already have the answer. I'd use a UF5408 (ultra fast general purpose diode for up to 1KV) because I have bought 200 of these in the past and still have most of them, and a capacitor. I also have made a string of 10 of these diodes in series to make sure they can handle the voltage. Use DC and a resistor to measure the forward voltage drop.


Ernst.

[thx1138]

Tesla's original patent that was applied for September 2, 1897 was for transmission of industrial scale power between tethered balloons maintained at 30,000 feet. The altitude has two properties that are beneficial to transmission: rarefied air and -40C temperature.
Nikola Tesla U.S. Patent 645,576 - System of Transmission of Electrical Energy | Tesla Universe

In the preface to the Colorado Springs Notes there is an drawing of a device he built as a demonstration for a patent examiner which used an evacuated glass tube to simulate the rarefied air.
Colorado Springs Notes 1899-1900

There are several entries in the Colorado Springs Notes that talk about how to electrically extract hydrogen from the air to maintain the balloons at altitude. Tesla never, however, attempted the transmission between balloons. There would surely be articles and photos of such an endeavor. That's probably a good thing because the jet stream was unknown at the time and can have winds of +250 MPH at that altitude which would have played havoc with the balloons.

It's not exactly clear when he determined he didn't need the balloons but read the July 4, 1899 notes about lightning storms he tracked on the plains of Colorado at the link above. That entry ends with "(This is of immense importance)". But on July 5, 1899 there is another note about extracting hydrogen for the balloons so he didn't immediately recognize the importance of the lightning storms. One thing to note is that he saw ground to cloud lightning in those observations but didn't recognize it as such. Interestingly, the first high speed recording of ground to cloud lightning were taken by a lab near Colorado Springs.
https://www.youtube.com/watch?v=6NZ7BollRo4

After he came back from Colorado springs is when the drawings and patents with the mushroom shape cupola were developed. It's interesting to note that the ground plates shown in the drawings are almost an aside when actually Wardenclyffe had a huge underground grounding system that went 250' deep and had spokes radially extending from the center.

Considering the July 4, 1899 notes, here's what I think Wardenclyffe was supposed to do. The cupola was a huge capacitor to accumulate charge from the generator that was installed at the site. The system drove the voltage up to millions of volts and discharged it into the ground. It would be the same thing as lightning striking the same point on every pulse and by controlling the frequency of the pulses Tesla could control where the nodal points of the waves were located and he could build a resonance by striking that point again just as the reflected wave arrived back at the origin. The planet earth was an integral part of the machine. Tesla even mentions lightning in some of his patents.

I'm not at all sure how plate tectonics would have affected that plan but plate tectonics were unknown at the time, or at least not accepted, until the 1960's.