Building Coaxial transmission line on PCB?

[John_H]

Like a polyphase switcher with *big* inductors?

But I don't want "almost zero ripple", I want the real thing.

John

Read up on the Cuk converter. Slobodan Cuk's topology.

Without the proper balance, you may get ripple. I've also seen one opinion
that the Cuk topology *can't* regulate with a stable feedback but I haven't
seen reason for this myself. Simulations with "ideal transformers" back in
'89 had input and output currents both going dead-flat solid after the
startup.


(posting to the newsgroup I know John Larkin visits, cross-posts removed to
the newsgroup I visit)

 

[John Larkin]

All it takes is an infinite capacity capacitor. The turn-on time
and inrush current may be high. However it avoids the need for a
UPS. Once they get the breakdown voltage up and get them into
production we can have all the electric cars we want, and dispense
with all batteries.

Right. You'd buy them charged, guaranted to run for 200K miles.

John

 

[msg]

This is interesting:

http://www.engr.wisc.edu/groups/green/ultra.html

Regards,

Michael

 

[MassiveProng]

Sorry, but that feature is only available on the 0 volt model.

Are they fooly regulated?

 

[MassiveProng]

All it takes is an infinite capacity capacitor. The turn-on time
and inrush current may be high. However it avoids the need for a
UPS. Once they get the breakdown voltage up and get them into
production we can have all the electric cars we want, and dispense
with all batteries.

You ain't real bright. You must have been daydreaming about
perpetual motion when the instructor covered this subject.

 

[MassiveProng]

Zero ripple is a real thing.

Bullshit.

The last supply I designed with our engineering group was for a CAT
scanner, and it was EXACTLY 1500 volts, regulated to within one volt,
and it had 2mV of ripple. That was AT the switching frequency of
17kHz at the full 250 Watts output.

That took a half year and two iterations to achieve.

We also made an xray supply that made 4kV at 1.5uA, and that had
only 2mV of ripple at rated loading.

Linear OR switcher, under full rated load, there IS going to be
ripple voltages present. Period.

You cannot look at a supply with no load on it, and declare it to be
ripple free. You are compiling errant data if you do.

Try again, Vlad.

 

[Vladimir Vassilevsky]

Zero ripple is a real thing. Imagine the two identical bucks
operating 50/50 duty with 180 degree phase shift on the common load.
Ideally, there will be no ripple at the load at all. There are
numerous patents on the variations of this idea, allowing to adjust
the duty, different topologies and such.


Bullshit.

I don't beleive you didn't understand what is the previous quoting about.

The last supply I designed with our engineering group was for a CAT
scanner, and it was EXACTLY 1500 volts, regulated to within one volt,
and it had 2mV of ripple.

It could be done better then that.

That was AT the switching frequency of
17kHz at the full 250 Watts output.
That took a half year and two iterations to achieve.

Good for you. Although very slow.

We also made an xray supply that made 4kV at 1.5uA, and that had only
2mV of ripple at rated loading.

1.5uA is not much.

Linear OR switcher, under full rated load, there IS going to be
ripple voltages present. Period.

You don't have to preach that 2 + 2 = 4.

You cannot look at a supply with no load on it, and declare it to be
ripple free. You are compiling errant data if you do.
Try again, Vlad.

I don't care. It is not my problem.


VLV

 

[MassiveProng]

It could be done better then that.

Not in the package constraints we had. We bettered the competitor's
product as well. They were unable to achieve the spec.

Do you even know what that ripple figure represents?

That's 0.000001333 % ripple.

You won't be getting lower than that any time soon in the chassis we
did it in at 250 Watts loading.

I don't think you are aware of what is or is not "being done".

You're just spittin' out words to see where they splatter.

 

[MassiveProng]

Good for you. Although very slow.

Nope. It was dual audio amps feeding a center tapped transformer and
multiplier stage. We found the right frequency for the application
with the hardware topology we used.

 

[MassiveProng]

1.5uA is not much.

You don't know much about X-ray flux, or the generation thereof.

 

[MassiveProng]

You don't have to preach that 2 + 2 = 4.

Aren't you the dolt that claimed that zero ripple supplies are easy
to make?

 

[MassiveProng]

I don't care. It is not my problem.

Why are you even in the fucking thread then, dipshit?

 

[Vladimir Vassilevsky]

Not in the package constraints we had. We bettered the competitor's
product as well. They were unable to achieve the spec.

Do you even know what that ripple figure represents?

Yes, I do know that very well, since I do work on the audio and
measurement equipment.

That's 0.000001333 % ripple.

This is -117dB. No doubts it is a decent result, although it is not a
world record by any means.

You won't be getting lower than that any time soon in the chassis we
did it in at 250 Watts loading.
I don't think you are aware of what is or is not "being done".
You're just spittin' out words to see where they splatter.

I can't understand. Are you trying to scare a porcupine by showing him a
naked butt?

VLV

 

[Vladimir Vassilevsky]

Aren't you the dolt that claimed that zero ripple supplies are easy
to make?

Dude, do you read the words which I didn't wrote?
Please find a quote or go take your pills.

VLV

 

[Vladimir Vassilevsky]

Why are you even in the fucking thread then, dipshit?

And this is not your problem.

VLV

 

[Vladimir Vassilevsky]

You don't know much about X-ray flux, or the generation thereof.

Sorry, dude. At one time I was working with the X-ray crystallograph.
The tube was typically operating at 40...50kV, draining the current
about 10..15mA. So here we go.

VLV

 

[MassiveProng]

This is -117dB. No doubts it is a decent result, although it is not a
world record by any means.

For a power supply?

You're nuts. ESPECIALLY at 1500 volts.

 

[MassiveProng]

And this is not your problem.

VLV

And you can **** off.

 

[MassiveProng]

Please find a quote or go take your pills.

I got a pill for your ass, fuckhead.

 

[MassiveProng]

Sorry, dude. At one time I was working with the X-ray crystallograph.
The tube was typically operating at 40...50kV, draining the current
about 10..15mA. So here we go.

And THAT supply ALSO had a pretty low ripple figure, I'll guarantee
you.

The whole idea behind clean DC for the X-ray tube is that the X-ray
flux is clean and pure. THAT yields the best contrast ratio in the
imagery.

The supply I mentioned feeds a small device meant for looking at gas
pipes in city streets.

I also made a supply that was 50kV at 250Watts That's only 5mA.

So your supplies were leaning toward a kW, eh? That must have been
some X-ray flux.

Still, you should have known that the ripple figure I gave for the
CAT supply was exceedingly low. By ALL standards.