Reply by Nomadic Electron September 8, 20182018-09-08
Thanks heaps I'll look at it tomorrow
Reply by John Larkin September 8, 20182018-09-08
On Sat, 8 Sep 2018 13:42:21 -0700 (PDT), Nomadic Electron
<themerchantbay@gmail.com> wrote:

>Hey guys. I made a simulation of the 2 stage boost converter idea using LTSpice. The simulation shows an efficiency of 91% with 120 Watts output power at a nominal 400 volt output. I selected capacitors, diodes and MOSFETS for each of the boost stages but haven't selected the inductors yet. Let me know what you think, is this efficiency too good to be true? here is the link to the LTSpice schematic: https://www.dropbox.com/s/ty1b9tcsxka2xsf/LT3758A%20cascaded%20two%20stage%20400V%20boost.asc?dl=0 > >This is a school project for me and i don't need to actually build it but it would be very fun to actually prototype it. There's more i have to do but i'll get onto that next with your advice again.
Here's your 2-stage boost with Win's idea of using a single controller chip: https://www.dropbox.com/s/anl2ptvf2lnbsei/boost_WJ.asc?dl=0 -- John Larkin Highland Technology, Inc lunatic fringe electronics
Reply by Nomadic Electron September 8, 20182018-09-08
On Sunday, 9 September 2018 06:42:26 UTC+10, Nomadic Electron  wrote:
> Hey guys. I made a simulation of the 2 stage boost converter idea using LTSpice. The simulation shows an efficiency of 91% with 120 Watts output power at a nominal 400 volt output. I selected capacitors, diodes and MOSFETS for each of the boost stages but haven't selected the inductors yet. Let me know what you think, is this efficiency too good to be true? here is the link to the LTSpice schematic: https://www.dropbox.com/s/ty1b9tcsxka2xsf/LT3758A%20cascaded%20two%20stage%20400V%20boost.asc?dl=0 > > This is a school project for me and i don't need to actually build it but it would be very fun to actually prototype it. There's more i have to do but i'll get onto that next with your advice again.
capacitor C11 is: https://au.mouser.com/ProductDetail/871-B32774P6475K000
Reply by Nomadic Electron September 8, 20182018-09-08
Hey guys. I made a simulation of the 2 stage boost converter idea using LTSpice. The simulation shows an efficiency of 91% with 120 Watts output power at a nominal 400 volt output. I selected capacitors, diodes and MOSFETS for each of the boost stages but haven't selected the inductors yet. Let me know what you think, is this efficiency too good to be true? here is the link to the LTSpice schematic: https://www.dropbox.com/s/ty1b9tcsxka2xsf/LT3758A%20cascaded%20two%20stage%20400V%20boost.asc?dl=0

This is a school project for me and i don't need to actually build it but it would be very fun to actually prototype it. There's more i have to do but i'll get onto that next with your advice again.
Reply by George Herold September 8, 20182018-09-08
On Friday, September 7, 2018 at 2:48:57 PM UTC-4, Lasse Langwadt Christensen wrote:
> fredag den 7. september 2018 kl. 20.34.41 UTC+2 skrev John Larkin: > > On Fri, 7 Sep 2018 09:16:57 -0400, Phil Hobbs > > <pcdhSpamMeSenseless@electrooptical.net> wrote: > > > > >On 09/04/2018 05:12 PM, John Larkin wrote: > > >> On Tue, 4 Sep 2018 13:56:38 -0700 (PDT), jurb6006@gmail.com wrote: > > >> > > >>>> "I think the record player speed regulator was frictional hence lossy. " > > >>> > > >>> Yes but against a spring that's wound up that is exactly what is needed. Electric motor not so much... > > >> > > >> I could imagine a nearly lossless regulator for a wind-up Victrola, > > >> but not with 1930's technology. > > >> > > >> > > > > > >Well, one could use a wristwatch-type escapement and a fluid damper. > > >Might not be super durable! > > > > > >Cheers > > > > > >Phil Hobbs > > > > There are several theoretically lossless variable-ratio gadgets. One > > uses a belt that can be positioned between tapered shafts. Another > > moves a roller at adjustable radius from a rotating disk. The latter > > was used in analog computers for aiming guns and torpedoes. > > variable ratio, clutch and forward-reverse all in one > > https://youtu.be/ezcxi6zRIuk?t=18m3s
The wheel drive on my snow blower works like that.. rubber disc and rubber rimmed driven wheel. It works the same way with the disc always spinning. George H.
Reply by Lasse Langwadt Christensen September 7, 20182018-09-07
fredag den 7. september 2018 kl. 20.34.41 UTC+2 skrev John Larkin:
> On Fri, 7 Sep 2018 09:16:57 -0400, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > > >On 09/04/2018 05:12 PM, John Larkin wrote: > >> On Tue, 4 Sep 2018 13:56:38 -0700 (PDT), jurb6006@gmail.com wrote: > >> > >>>> "I think the record player speed regulator was frictional hence lossy. " > >>> > >>> Yes but against a spring that's wound up that is exactly what is needed. Electric motor not so much... > >> > >> I could imagine a nearly lossless regulator for a wind-up Victrola, > >> but not with 1930's technology. > >> > >> > > > >Well, one could use a wristwatch-type escapement and a fluid damper. > >Might not be super durable! > > > >Cheers > > > >Phil Hobbs > > There are several theoretically lossless variable-ratio gadgets. One > uses a belt that can be positioned between tapered shafts. Another > moves a roller at adjustable radius from a rotating disk. The latter > was used in analog computers for aiming guns and torpedoes.
variable ratio, clutch and forward-reverse all in one https://youtu.be/ezcxi6zRIuk?t=18m3s
Reply by John Larkin September 7, 20182018-09-07
On Fri, 7 Sep 2018 09:16:57 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

>On 09/04/2018 05:12 PM, John Larkin wrote: >> On Tue, 4 Sep 2018 13:56:38 -0700 (PDT), jurb6006@gmail.com wrote: >> >>>> "I think the record player speed regulator was frictional hence lossy. " >>> >>> Yes but against a spring that's wound up that is exactly what is needed. Electric motor not so much... >> >> I could imagine a nearly lossless regulator for a wind-up Victrola, >> but not with 1930's technology. >> >> > >Well, one could use a wristwatch-type escapement and a fluid damper. >Might not be super durable! > >Cheers > >Phil Hobbs
There are several theoretically lossless variable-ratio gadgets. One uses a belt that can be positioned between tapered shafts. Another moves a roller at adjustable radius from a rotating disk. The latter was used in analog computers for aiming guns and torpedoes. You can see such a computer onboard the submarine Bowfin at Pearl Harbor. It's worth the trip if you are ever in Hawaii. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Reply by Phil Hobbs September 7, 20182018-09-07
On 09/04/2018 05:12 PM, John Larkin wrote:
> On Tue, 4 Sep 2018 13:56:38 -0700 (PDT), jurb6006@gmail.com wrote: > >>> "I think the record player speed regulator was frictional hence lossy. " >> >> Yes but against a spring that's wound up that is exactly what is needed. Electric motor not so much... > > I could imagine a nearly lossless regulator for a wind-up Victrola, > but not with 1930's technology. > >
Well, one could use a wristwatch-type escapement and a fluid damper. Might not be super durable! Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net https://hobbs-eo.com
Reply by September 6, 20182018-09-06
>"looks like two Dickson multipliers in parallel "
Somebody called it "a" Dickson convertor. I went with that. That came out of my head but like all the other things I invented I was not the first. (I got all of them with my DVD rewinder though)
Reply by September 6, 20182018-09-06
>"Are there wires between the collectors and the arrows? "
Umm, actually no. If the heatsinks are grounded it is a simple matter to leave out the insulators, assuming a metal tab or as in the case of my little box the cases of TO-3 transistors.