Competition: High Voltage Power Supply

[tvtech]

I couldn't say for sure, tvtech. I suppose a little anonymity couldn't hurt when you're hosting a competition. Helps keep you separate from the participants until the end.

Regards

This thread is beginning to look like an Agatha Christie novel... WTF is going on here?

Anybody know the plot. Who dies first...the Designer, Inventor or a Random Forum Member

Regards,
tvtech

 

[DerStrom8]

This thread is beginning to look like an Agatha Christie novel... WTF is going on here?

Anybody know the plot. Who dies first...the Designer, Inventor or a Random Forum Member

Regards,
tvtech

Hahaha, you're right Didn't realize how this all was starting to look. Hopefully you got my point though

 

[tcmtech]

And 60 mA is NOWHERE near enough to draw it out a foot. 60mA at 20kv will only get you about 3 inches, max.

Then my 12 KV 60 Ma neon sign transformers must have very conservative ratings being when I used them for Jacobs ladders I had to have the top of the ladder rods at least 8" apart to consistently break the arcs.

Now, are you thinking of participating in the competition or not? If no, then stop picking at it. There is more than enough information there for this project to be completed, and for a winner to be selected. You don't need any specific details.

I already made my idea submissions and got shot down.

Post 14, Arcs Vs sparks issue.Nope.

Post 18, Over clocked and over driven driven 15 KV NST with inverter controled what nots. Nope. too heavy.

Post 20, two variacs and NST. Too heavy.

Post 33. Common flyback transformer with single transistor power oscillator. Nope. Now I am just picking.
--------------------------------------------------

So lets all of us get this strait on what it isn't.

No NST's or the like. Out for being too heavy/bulky.

Common CRT flybacks cant come close to the requested output power requirements but that's what the design should be built like.

There is a criteria of it can be AC or DC but it has to make arcs not sparks.

There is leeway on the design and output but not relating to what anyone has posted so far.

It has to somewhat match the characteristics of a flyback transformer but the defined requirements are way beyond what any off the shelf flyback can deliver.

The OP is open to anything but what has been suggested.

It has to run for 24 hours continuous duty but has no defined/specified input power source criteria.

What the contest sponsor wants cant be accurately defined but what he doesn't want can but only after its suggested.


Clear as mud to me.

I give up but I will be watching with morbid curiosity to see where this leads.

 

[tvtech]

Then my 12 KV 60 Ma neon sign transformers must have very conservative ratings being when I used them for Jacobs ladders I had to have the top of the ladder rods at least 8" apart to consistently break the arcs.



I already made my idea submissions and got shot down.

Post 14, Arcs Vs sparks issue.Nope.

Post 18, Over clocked and over driven driven 15 KV NST with inverter controled what nots. Nope. too heavy.

Post 20, two variacs and NST. Too heavy.

Post 33. Common flyback transformer with single transistor power oscillator. Nope. Now I am just picking.
--------------------------------------------------

So lets all of us get this strait on what it isn't.

No NST's or the like. Out for being too heavy/bulky.

Common CRT flybacks cant come close to the requested output power requirements but that's what the design should be built like.

There is a criteria of it can be AC or DC but it has to make arcs not sparks.

There is leeway on the design and output but not relating to what anyone has posted so far.

It has to somewhat match the characteristics of a flyback transformer but the defined requirements are way beyond what any off the shelf flyback can deliver.

The OP is open to anything but what has been suggested.

It has to run for 24 hours continuous duty but has no defined/specified input power source criteria.

What the contest sponsor wants cant be accurately defined but what he doesn't want can but only after its suggested.


Clear as mud to me.

I give up but I will be watching with morbid curiosity to see where this leads.

Hi tcm

I will be watching only too.

Gotta see how this unfolds

tvtech

 

[jpanhalt]

Voltage doublers change the arcs into sparks.

Regards,
Matt

I am not quite sure what you mean by that.

Using either higher frequency or large (expensive) capacitors, you can meet the requirements for voltage and current with a neon sign transformer (or similar) plus a 2 stage multiplier. At 60hz, and a 10% voltage drop, you would need something like 1.2 uF capacitors (!).

Now, of course, the transformer won't fit in the designed space. X-ray machines have been around a long time as has HV physics, and so far as I could find, that basic design , i.e., a transformer to get to ≈ 5000 to 6000V followed by a voltage multiplier, is still being used.

You could up the frequency and reduce the capacitors proportionately, but you are still going to have some expensive components. Do you have that stuff on your shelf at home?

John

 

[DerStrom8]

Okay, I am only responding to this because I think it will help some of the members here who are actually interested in trying to make it work, rather than just picking on the competition.

So lets all of us get this strait on what it isn't.

No NST's or the like. Out for being too heavy/bulky.

Correct.

Common CRT flybacks cant come close to the requested output power requirements but that's what the design should be built like.

The original output power requirements were very rough since the host was not sure of the output specs that he really wanted. He has since specified that it simply has to operate like it would in its original TV application.

There is a criteria of it can be AC or DC but it has to make arcs not sparks.

The output of a flyback transformer is already DC. The host has since specified that that is what he would prefer.

There is leeway on the design and output but not relating to what anyone has posted so far.

If you're referring to your suggestions, they were too far outside the preferred boundaries, namely in the weight and size category.

It has to somewhat match the characteristics of a flyback transformer but the defined requirements are way beyond what any off the shelf flyback can deliver.

You're repeating yourself now. Look at the third item in your list.

The OP is open to anything but what has been suggested.

Again. See the 5th item in your list.

It has to run for 24 hours continuous duty but has no defined/specified input power source criteria.

Correct. That is for the designer to decide.

What the contest sponsor wants cant be accurately defined but what he doesn't want can but only after its suggested.

Most of the ideas that have been turned down directly go against what was already specified in the criteria. Anything else has been edited into the first post.

Enjoy the show tcm.

 

[DerStrom8]

I am not quite sure what you mean by that.

Using either higher frequency or large (expensive) capacitors, you can meet the requirements for voltage and current with a neon sign transformer (or similar) plus a 2 stage multiplier. At 60hz, and a 10% voltage drop, you would need something like 1.2 uF capacitors (!).

Now, of course, the transformer won't fit in the designed space. X-ray machines have been around a long time as has HV physics, and so far as I could find, that basic design , i.e., a transformer to get to ≈ 5000 to 6000V followed by a voltage multiplier, is still being used.

You could up the frequency and reduce the capacitors proportionately, but you are still going to have some expensive components. Do you have that stuff on your shelf at home?

John

Sorry, anytime I've used a doubler or tripler, it's turned an arc into a series of loud sparks, due to the output waveform and the energy stored in the capacitors each half cycle. I suppose there are ways around that, I've just never seen it. I should not have jumped to conclusions though.

 

[jpanhalt]

I am sure you have seen this calculator: **broken link removed**

If you assume that there will be some sort of voltage multiplier, you can play with the numbers to test for reality.

Here are some other sources you may have seen:
https://www.electro-tech-online.com/custompdfs/2013/01/Multiplier20Design20Guideline.pdf
https://www.voltagemultipliers.com/
https://www.electro-tech-online.com/custompdfs/2013/01/anusingr.pdf

However, if you are not limited by reality, then this Instructable presumably tells how to get a 0-50KV variable supply at 20 mA:

https://www.instructables.com/id/High-Voltage-Multiplier/

I couldn't find any experimental documentation of that claim in it, but that is the claim and how it is indexed.

I am not trying to shoot down the next X-Prize in HV physics. I think this project is doable within the bounds of what is known, except for weight and size.

John

Edit: Are superconductors and exotic insulation materials ruled out?

 

[DerStrom8]

The host has responded and has asked me to add these new specs. I will also add it to the first post:

1. Try to keep the cost under $150.00us. Includes Shipping.
3. Focus on how you can sustain an Arc 24hrs at 20k without burning things up. That's the question. If it's a Flyback design, how far would you push it? Only 1ma? So be it. If it's a NST, again, how far would you push it? The same question goes for the tripler John suggested. How far can you push it, and what would be the sacrifices in order to get 20kv? These are the questions for the contestants to answer for themselves.
4. Allow NST's (solid state type, due to their small physical size and weight) and Tripler's, provided the cost remain under $150.

I realize things are changing up a lot, but that is because the project is not specific. The designers should make most of these decisions on their own.

Regards,
Matt

 

[tvtech]

The host has responded and has asked me to add these new specs. I will also add it to the first post:



I realize things are changing up a lot, but that is because the project is not specific. The designers should make most of these decisions on their own.

Regards,
Matt

Why can "the host"...not just "post" here?? Under an Alias ??.

Instead of this "host" nonsense?. Middleman Matt. Who can not answer all the "hosts" questions ??

Too tired for this game.

tvtech

 

[DerStrom8]

Why can "the host"...not just "post" here?? Under an Alias ??.

Instead of this "host" nonsense?. Middleman Matt. Who can not answer all the "hosts" questions ??

Too tired for this game.

tvtech

I don't know why the Host has elected to remain separated from this thread, but he has every right to. We are still in direct contact so that he can answer any questions you have. He chose me as a middleman because I was trying to help him out privately with the project at first, before he decided to make it into a competition.

 

[tvtech]

I don't know why the Host has elected to remain separated from this thread, but he has every right to. We are still in direct contact so that he can answer any questions you have. He chose me as a middleman because I was trying to help him out privately with the project at first, before he decided to make it into a competition.

Oh well, Sally says if I don't go to bed soon..I am toast. Don't want that.

Enjoy the "Host". Whoever that mysterious person might be.

As Charlie Harper often said......" I have a bad feeling about this".

Regards,
tvtech

 

[DerStrom8]

Oh well, Sally says if I don't go to bed soon..I am toast. Don't want that.

Enjoy the "Host". Whoever that mysterious person might be.

As Charlie Harper often said......" I have a bad feeling about this".

Regards,
tvtech

To be honest, I don't see what the problem is. He will probably reveal himself at the end.

Now, is anyone actually interested in giving this a try? Or is everyone just going to complain that there's not enough information? It would be good to know what's happening

Regards,
Matt

 

[Nigel Goodwin]

Now, is anyone actually interested in giving this a try? Or is everyone just going to complain that there's not enough information? It would be good to know what's happening

I would have thought chances are slim

"Small reward given for creation of unknown project, applicants must wear a blindfold, have one hand tied behind their back, and the fingers of their other hand broken".

 

[DerStrom8]

I would have thought chances are slim

"Small reward given for creation of unknown project, applicants must wear a blindfold, have one hand tied behind their back, and the fingers of their other hand broken".

It seems you are misunderstanding this just as much as other people are. This design is about ingenuity and overall design technique. The designs are merely a method to judge the contestants' ability to take a small amount of information and materials, and put it together in the cleverest way possible.

The applicants are not blindfolded, nor do they have a hand tied behind their back or fingers broken. In fact, it's the absolute opposite. They're completely free to do whatever they want provided it produces an operational device.

I honestly don't see why people are having problems with this. The guidelines are not very strict. It simply has to provide a ~20kv output, variable voltage and current, not weigh a whole lot or take up too much space, and be as cheap as possible. The rest is really up to you.

 

[DerStrom8]

In hopes that it might induce a little INTEREST in the competition, the host has upped the prize to $100 under one condition: Stop asking questions and put your mind and ingenuity to work!

If you use the given criteria to create a design, you will have a good chance of winning. It's that simple.

 

[DerStrom8]

So just to get an idea, who is interested in participating? Again, the grand prize has been increased to $100!

 

[jpanhalt]

How close is the circuit in this post to what your sponsor wants?

https://www.electro-tech-online.com...nd-resistors-in-an-oscillator-circuit.132567/

John

 

[DerStrom8]

How close is the circuit in this post to what your sponsor wants?

https://www.electro-tech-online.com...nd-resistors-in-an-oscillator-circuit.132567/

John

I will have to ask the Host, but I think it's fairly close. All that it's missing is an adjustable voltage and current output. Also not sure about the two transformers. I don't think it will be a problem, but again, I'll ask the host.

Thanks for the input John

 

[jpanhalt]

The voltage is probably most easily controlled at the input, e.g., a variable transformer. As for current, most of the modern self-oscillating, half-bridge drivers I could find only operate at 50% duty cycle ±2%. Fairchild makes one that can be externally driven to give adjustable duty cycle, FAN7387 (https://www.electro-tech-online.com/custompdfs/2013/01/FAN7387.pdf).

It is interesting that IR compares its drivers to an NE555, but they do not have separate charge and discharge paths. I wonder whether the same approach (i.e., external PWM drive) as used on the FAN7387 could be used with the IR driver to get variable duty cycle and current control. Anyway, how important is current control, if you can control voltage or vice versa?

John