Factor PFC Into Your Power-Supply Design

So Jan has only just found out about it. It's been a requirement for everything except the tiniest power supplies for decades now.

Anthony William Sloman snipped-for-privacy@ieee.org wrote in news: snipped-for-privacy@googlegroups.com:

We had AC driven supplies we incorporated PFC into. One was a low voltage military PC Chassis supply that ran on AC line voltage between 85 and 265 VAC 60Hz and autoswitched. It needed to be bale to run at the end of a distribution drop in Japan (100VAC), which can be as low as 85 Volts, but typically never drops below 90 V, but that was our low line spec. OR it could run off 48VDC OR battery, whichever was available, it would switch to. It consumed enough power that we made it a PFC design on the AC driven driven front end.

Our HVDC supplies, however, were mostly of such low wattage and were almost all low voltage DC powered, so no PFC was needed.

We did have a couple HVDC supplies that were big enough and were AC driven on the front end, that we made them as corrected designs. One ended up taking up about a third of one of those short racks that were like 20U tall. But most of our stuff would fit into a pack of cigarettes and were DC driven.

It's impossible to make your own PFC power supplies at the cost of buying them.

We buy a kilowatt Mean Well 48 volt supply for $156. It has emi filters, a nice enclosure, an internal fan, and all sorts of compliance stickers.

On a sunny day (Sun, 16 Oct 2022 08:54:49 -0700) it happened John Larkin snipped-for-privacy@highlandSNIPMEtechnology.com wrote in snipped-for-privacy@4ax.com:

Sure I have a whole bunch of Meanwell 7 V 20 A put those in series if In eed more volts:

But that article was informative, and about electronics for a change, and you never know, is not Meanwell made in China (Taiwan New Taipei City) :-)

That is fine if your product is very expensive in the first place and BOM price isn't quite as important. Highland Technology is kind of niche though, isn't it ?

Depends on the output requirements too, of course.

boB

I couldn't buy parts to make the MeanWell equivalent at twice the price we pay for the whole thing. And their quality has been excellent. No assembly required.

High selling price doesn't mean we're happy to throw money away.

We are niche, but that's no reason to design our own power supplies. We most always buy the prime source, what connects to the AC line, which gets us a single big DC source to work with. Then we add, usually many, secondary regulators on our boards.

We use warts or laptop type supplies when we can. I don't want an AC connector on my box if I can avoid it.

We usually need a lot of supplies. I just increased my current design from 10 to 15 distinct power pour nets.

John Larkin snipped-for-privacy@highlandSNIPMEtechnology.com wrote in news: snipped-for-privacy@4ax.com:

That depends on how many are to be manufactured and sold by "you".

Incorporating a supply into a design is one thing and in a COTS realm choices can be made... however...

Being a power supply maker, part of our realm was incorporating PFC where it was needed or required. Being primarily a DC-to-DC HV supply maker, the issue did not arise much.

And... infant mortality... It's OK... They meant well, from their accountant's Point Of View.

I'm in the power supply business, but I start with a MeanWell 24 or

48V dc supply and work from there.

So far, we've had zero failures.

John Larkin snipped-for-privacy@highlandSNIPMEtechnology.com wrote in news: snipped-for-privacy@4ax.com:

No, TrumpChump, you are not. You USE power supplies in your products and have had to design a few of your own to incorporate directly in your designs, but AFAIK your company is a signal handling device maker, not a power supply maker.

Oh... you mean a supply from a PS vendor. Again, how does that make YOU a company which is "in the power supply business"?

Except for that major failure residing between your ears.

You are also a pathtic snipper of text as you respout your pathetic horeshit and ignore the entire post you responded to.

Another between the ears fail for you, Johnny.

We make three-phase 600 va alternator simulators

which pretend to have the impedance behavior of a permanent-magnet alternator, which typically drives a PWM shorting regulator. The silver thing on one side is the kilowatt MeanWell.

And we're about to introduce a modular multi-channel power supply/dummy load box.

We're doing a couple of low-voltage DC supply plugins now, but have high voltage and polyphase AC on the list.

We have an aerospace customer who builds giant test systems, Iron Bird level stuff. They were complaining about the hassle of buying and mounting and wiring goofy power supplies from multiple vendors, and then trying to synchronize them though a zillion weird hardware and software protocols. So we sensibly decided to revolutionize the power supply industry.

Always nice chatting with you. Keep in touch.

<snip>

Lenin did describe his program for Russia as socialism and rural electrification. I hope your revolutionary plans turn out better.

"Henceforth the rostrum at All-Russia Congresses will be mounted, not only by politicians and administrators but also by engineers and agronomists. This marks the beginning of that very happy time when politics will recede into the background, when politics will be discussed less often and at shorter length, and engineers and agronomists will do most of the talking."

John Larkin snipped-for-privacy@highlandSNIPMEtechnology.com wrote in news: snipped-for-privacy@4ax.com:

Wow... did Johnny make a departure from signal aquisition devices to these behemoths?

Whatever the contractor wants, eh?

That all looks like a way bigger menagerie than the stuff you used to make. A lot more labor goes into each one than your signal stuff. Must be a pain for you to make. Do you have it contract manufactured (the PCBs)?

What frequency is the output at?

We used to make a miniature 3 phase 440Hz supply for the mil gyros we used in the early steady cam stabilizers we made for the first steady cam inventor. Now they are all cantilever types. Back in the late '90s.

John Larkin snipped-for-privacy@highlandSNIPMEtechnology.com wrote in news: snipped-for-privacy@4ax.com:

Dang... you are doing 4U designs now. Is that a custom cabinet?

I made a rugged 4U tray design and the front panel was easily twice that thick. Must not be populated all that heavily.

mandag den 17. oktober 2022 kl. 22.23.58 UTC+2 skrev snipped-for-privacy@decadence.org:

heavy stuff don't just hang in the front plate

John Larkin snipped-for-privacy@highlandSNIPMEtechnology.com wrote in news: snipped-for-privacy@4ax.com:

Revolutionize? Hahahaha...

Ours went up to 400kV in the Euro part of the company. Over here, we only went up to about 50kV.

But our "Iron Bird" at one point were designs that went into space shuttle experiments.

Our smaller stuff went into high altitude balloons for NOAA. They were log amp driven. Those were beat up in their testing. We send three and only one goes up on the 'bird'.

We even had a 20 - 20k Hz 800V 2kW design that a company used to drive a piezo stack lathe head to make optical quality surfaces right off the lathe. The final cutter had a full 2mm transition, so on a lathe it could cut a square peg it moved so fast. But it was used to make giant one inch contact lens molds for race horses.

The power supply industry to fill such niche application is alway "revolotionary" and usually always custom to a single customer, which is why not many "off the shelf HV deigns are out there. All load situations differ at high voltages.

Yes. And it was fun.

We assemble everything ourselves. We buy parts, bare boards, and sheet metal.

120 Hz to 4 KHz.

A FADEC starts up using aircraft DC power but, after it manages engine startup, it gets its power from a redundant PM alternator on the engine itself.

The people who make it wouldn't send us specs, so we chuked it into a milling machine and spun it. I suspect we know more about it now than they do.

I'm planning a smaller alternator simulator to plug into our modular power system.

Linear? The alternators are regulated by shorting, which our box has to tolerate without blowing up. A PM alternator is pretty much a current source.

Yes. We designed it in SolidWorks and it was built by Protocase, all laser cut. They do really nice work.

Rack panels are standard and look strange if they are thicker than their neighbors. The heavy stuff needs trays or slides of course.

We don't want niche business, we want to change the world. Not much to ask for.

The problem with the power supply biz is the lack of interface standards. Even similar models from the same manufacturer have different and bizarre interfaces and connectors. There are horror stories.

Imagine persuading some motley collection of a couple dozen power supplies to make a precisely timed sequence of DC and AC outputs, with precise AC frequency and phase control and with timed dummy loads. It almost can't be done.

We don't have any HV customers yet, but we may as well plan it in the architecture. There are cases where people want a lot of channels of HV.

I don't know why you are so anti Meanwell. A product I have been involved with which uses a Meanwell encapsulated power supply module has shipped around

1500 units over a 5 year period and there have been zero reported failures. The Meanwells were chosen after evaluating a wide variety of different brands, including some well known US ones. The Meanwells had the lowest conducted emissions of any of the candidates (based on my own direct comparisons rather than the data sheets) and there was a detailed test report available which disclosed a lot of detail about which internal components were most highly stressed and what temperatures they would reach at maximum rated ambient temperature. They were also relatively cheap.

John