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DC transformer, x-Chapters 9x.16

Started by Winfield Hill October 20, 2019
 x-Chapters 9x.16, about DC transformers, AKA bus
 converters.  It's a synchronous dc-dc converter,
 with in/out voltage ratio set by a fixed switching
 duty cycle.  Like ac transformers, they transfer
 power in either direction, as a function of who's
 above the ratio.  The current-ratio also obeys
 the voltage-ratio rule, like an ac transformer. 
 As bus-converters, they're used to convert a 48V
 distributed bus, to lower voltages for local use.

https://www.dropbox.com/s/nrp5paq1j1u5756/9x.16_DC-xfmr.pdf?dl=1


-- 
 Thanks,
    - Win
Winfield Hill <winfieldhill@yahoo.com> wrote in news:qohu9001kk1
@drn.newsguy.com:

> x-Chapters 9x.16, about DC transformers, AKA bus > converters. It's a synchronous dc-dc converter, > with in/out voltage ratio set by a fixed switching > duty cycle. Like ac transformers, they transfer > power in either direction, as a function of who's > above the ratio. The current-ratio also obeys > the voltage-ratio rule, like an ac transformer. > As bus-converters, they're used to convert a 48V > distributed bus, to lower voltages for local use. > > https://www.dropbox.com/s/nrp5paq1j1u5756/9x.16_DC-xfmr.pdf?dl=1 > >
Anything in your book on how a big 10kVA line conditioning transformer works? You know, the ones with cap banks in them that put out at 60Hz even when the line or freq sags. We had a back up generator that caused our UPS systems to fail to notice the power being back up, and it was due to the generator somehow making not quite sinosidal waveform or maybe it was full of spikes... not sure, but these transformers in line with the generator output fixed the issue. "Sola" is the most common brand I see, and is what we installed in the house in Virginia. It was 750 Lbs overall for the 20kVA capacity we needed.
On 2019-10-20 17:25, Winfield Hill wrote:
> x-Chapters 9x.16, about DC transformers, AKA bus > converters. It's a synchronous dc-dc converter, > with in/out voltage ratio set by a fixed switching > duty cycle. Like ac transformers, they transfer > power in either direction, as a function of who's > above the ratio. The current-ratio also obeys > the voltage-ratio rule, like an ac transformer. > As bus-converters, they're used to convert a 48V > distributed bus, to lower voltages for local use. > > https://www.dropbox.com/s/nrp5paq1j1u5756/9x.16_DC-xfmr.pdf?dl=1 > >
Nice chapter! Fig 9.2.73, upper right terminals should be Vout(HV) not Vout(LV). Arie
Winfield Hill wrote...
> > x-Chapters 9x.16, about DC transformers, AKA bus > converters. It's a synchronous dc-dc converter, > with in/out voltage ratio set by a fixed switching > duty cycle. Like ac transformers, they transfer > power in either direction, as a function of who's > above the ratio. The current-ratio also obeys > the voltage-ratio rule, like an ac transformer. > As bus-converters, they're used to convert a 48V > distributed bus, to lower voltages for local use. > >https://www.dropbox.com/s/nrp5paq1j1u5756/9x.16_DC-xfmr.pdf?dl=1
The circuit schematic and PCB board in the photo is PWR-671, in my RIS-671 project file. It uses an IR2085 for PWM and MOSFET driving, and has a zener+7812, so Vmax could be up to 450V, if R13, D3, elec caps, and MOSFETs are chosen properly. https://www.dropbox.com/s/wy58c0yxuc6lda8/PWR-671-1_pcb.pdf?dl=1 I first created it for a magnet-control project. Three different voltages were needed, with 150W capability, this way we needed only one module. As the field coils were switched on and off, the energy went back into the big source-supply cap. -- Thanks, - Win
Arie de Muynck wrote...
> >On 2019-10-20 17:25, Winfield Hill wrote: >> x-Chapters 9x.16, about DC transformers, AKA bus >> converters. It's a synchronous dc-dc converter, >> with in/out voltage ratio set by a fixed switching >> duty cycle. Like ac transformers, they transfer >> power in either direction, as a function of who's >> above the ratio. The current-ratio also obeys >> the voltage-ratio rule, like an ac transformer. >> As bus-converters, they're used to convert a 48V >> distributed bus, to lower voltages for local use. >> >> https://www.dropbox.com/s/nrp5paq1j1u5756/9x.16_DC-xfmr.pdf?dl=1 > > Nice chapter! > > Fig 9.2.73, upper right terminals should be Vout(HV) not Vout(LV).
Thanks, Arie, I've made a note for our next printing. -- Thanks, - Win
Winfield Hill wrote...
> >Winfield Hill wrote... >> >> x-Chapters 9x.16, about DC transformers, AKA bus >> converters. It's a synchronous dc-dc converter, >> with in/out voltage ratio set by a fixed switching >> duty cycle. Like ac transformers, they transfer >> power in either direction, as a function of who's >> above the ratio. The current-ratio also obeys >> the voltage-ratio rule, like an ac transformer. >> As bus-converters, they're used to convert a 48V >> distributed bus, to lower voltages for local use. >> >>https://www.dropbox.com/s/nrp5paq1j1u5756/9x.16_DC-xfmr.pdf?dl=1 > > The circuit schematic and PCB board in the photo > is PWR-671, in my RIS-671 project file. It uses > an IR2085 for PWM and MOSFET driving, and has a > zener+7812, so Vmax could be up to 450V, if R13, > D3, elec caps, and MOSFETs are chosen properly. > >https://www.dropbox.com/s/wy58c0yxuc6lda8/PWR-671-1_pcb.pdf?dl=1
Correction: Although most of IR's HV MOSFET driver ICs work to 600V, the IR2085 is only good to 130V. But it's faster, with deadtimes as low as 50ns.
> I first created it for a magnet-control project. > Three different voltages were needed, with 150W > capability, this way we needed only one module. > As the field coils were switched on and off, the > energy went back into the big source-supply cap. > >
-- Thanks, - Win
s&oslash;ndag den 20. oktober 2019 kl. 18.19.59 UTC+2 skrev Winfield Hill:
> Winfield Hill wrote... > > > > x-Chapters 9x.16, about DC transformers, AKA bus > > converters. It's a synchronous dc-dc converter, > > with in/out voltage ratio set by a fixed switching > > duty cycle. Like ac transformers, they transfer > > power in either direction, as a function of who's > > above the ratio. The current-ratio also obeys > > the voltage-ratio rule, like an ac transformer. > > As bus-converters, they're used to convert a 48V > > distributed bus, to lower voltages for local use. > > > >https://www.dropbox.com/s/nrp5paq1j1u5756/9x.16_DC-xfmr.pdf?dl=1 > > The circuit schematic and PCB board in the photo > is PWR-671, in my RIS-671 project file. It uses > an IR2085 for PWM and MOSFET driving, and has a > zener+7812, so Vmax could be up to 450V, if R13, > D3, elec caps, and MOSFETs are chosen properly. > > https://www.dropbox.com/s/wy58c0yxuc6lda8/PWR-671-1_pcb.pdf?dl=1 > > I first created it for a magnet-control project. > Three different voltages were needed, with 150W > capability, this way we needed only one module. > As the field coils were switched on and off, the > energy went back into the big source-supply cap. >
what on earth was that schematic drawn in?
Win, you really need to cover Royer and Royer Jensen converters. That was the original DC Transformers

Williams paper on optimising Roger efficiency is excellent 

Cheers

Klaus
klaus.kragelund@gmail.com wrote...
> > Win, you really need to cover Royer and Royer Jensen > converters. That was the original DC Transformers > > Williams paper on optimising Roger efficiency is excellent
Thanks, Klaus, I'm sure you're right. But I have very little experience with them at this point. Maybe you'd like to conribute a guest section? -- Thanks, - Win
On Monday, 21 October 2019 19:31:03 UTC+2, Winfield Hill  wrote:
> klaus.kragelund@gmail.com wrote... > > > > Win, you really need to cover Royer and Royer Jensen > > converters. That was the original DC Transformers > > > > Williams paper on optimising Roger efficiency is excellent > > Thanks, Klaus, I'm sure you're right. But I have > very little experience with them at this point. > Maybe you'd like to conribute a guest section? >
Certainly, all though I am no expert, still more to learn I will send you a message on LinkedIn Cheers Klaus