Search:

Type: Posts; User: treez

Page 1 of 20 1 2 3 4

Search: Search took 0.06 seconds.

  1. Replies
    23
    Views
    656

    Closed: Re: Flyback Airgap Doubts?

    (i'll say nothing, i got my brains smashed up once when asked to design Cuk's single stage isolated PFC'd Cuk converter for an EV charger at 3000W...after a week, all i had was a sim which didnt seem...
  2. Replies
    23
    Views
    656

    Closed: Re: Flyback Airgap Doubts?

    That's a great link...see Dr Slobodan Cuk of Tesla is talking air gaps there.
  3. Replies
    23
    Views
    656

    Closed: Re: Flyback Airgap Doubts?

    here i attach ltspice with LPRI = 1mH...just for sake of argument...and to keep it in DCM......i had to reduce the fsw to 16khz......and adjust LSEC accordingly....
    You can also play about with...
  4. Replies
    23
    Views
    656

    Closed: Re: Flyback Airgap Doubts?

    Well...i made it just on the border of DCM/CCM at 270VDC with 226uH = LPRI and FSW=100khz......which is a good situation.

    If you increase LPRI, then you will no longer be on the border of dcm/ccm...
  5. Closed: Where to buy Electronics components in UK for domestic use?

    Hi,
    I am in UK.
    I have now bought two DAB radios (from supermarkets) and neither of them work on the switch mode mains adapter that they were supplied with. ( too much distortion/noise) .They do ...
  6. Replies
    23
    Views
    656

    Closed: Re: Flyback Airgap Doubts?

    I attach here the new transformer in the ltspice schem for DCM at 230VAC...in fact, its DCM down to 270vdc input on the HV bus, so you have some margin.
    The new NS/NP is 0.245
    I kept your...
  7. Replies
    23
    Views
    656

    Closed: Re: Flyback Airgap Doubts?

    if you dont have airgap in flyback txfmr then it will saturate immediately because when you power up it is on full load charging up the output capacitor.
    Can you get some gapped cores?...i feel...
  8. Replies
    23
    Views
    656

    Closed: Re: Flyback Airgap Doubts?

    Give me a shout if you want me to re-do your transformer for DCM over all VAC input?
    Please also tell what is your VAC input range?
  9. Replies
    1
    Views
    151

    Closed: Re: Practical (active) Fly Back Converter

    Do you want to know about....
    1...Operation of active clamp flyback?
    2...current mode control in flyback?
    3....A sinusoidal inverter using a full bridge?
  10. Closed: Re: FAN6754 flyback converter-overcurrent problem

    did you look at it with thermal camera?...see if anything getting hot...there is a good therm cam you can buy for £150...ask me and i will tell you part number.

    otherwise, strip it down and see...
  11. Replies
    23
    Views
    656

    Closed: Re: Flyback Airgap Doubts?

    Hi
    I did your flyback in LTSPICE. It is attached for you….This is the free sim from analog.com…..you can run it by simply converting it to .asc instead of .txt

    I gave you a vac input of...
  12. Closed: Re: The "cheap, quick and easy" way to do high power SMPS's?

    Thanks,
    The principle of the top post…..can it equivalently be done with two vicor DCM modules in parallel?....but this time with an error amplifier pulling down the TRIM pin on any DCM module...
  13. Closed: Re: The "cheap, quick and easy" way to do high power SMPS's?

    Thanks, I admit that one controller is better…..(eg one error amplifier for multiple units etc etc)……though in some ways I like the idea of a totally independent unit, that doesn’t need its control ...
  14. Closed: The "cheap, quick and easy" way to do high power SMPS's?

    Hi,
    Is this the “cheap, quick and easy way” to do high power SMPS’s?

    The attached shows two identical Two Transistor forward converters in parallel…..each is 1.2Kw (50vout and 24iout)
    If any...
  15. Closed: Heatsinking for Vicor DCDC modules on a test PCB?

    Hi,

    We are doing a Test PCB containing one Vicor BCM4414xH0E5035yzz module, which will feed 4 paralleled Vicor DCM3623x50M53C2yzz modules. (these are all DCDC modules)
    The BCM module will...
  16. Replies
    23
    Views
    921

    Closed: Re: Vicor Bus Converter module

    ...on the theme.......we could have eight identical paralleled 1.5Kw two transistor forwards……..and put a current limiter on the output of each one…….so that those that hogged hit their current...
  17. Replies
    13
    Views
    556

    Closed: Re: Off-line Power factor correction

    sorry here is the link to the smps course with the section on pfc...

    https://drive.google.com/open?id=0B7aRNbu3Fes4TU92Mkw3YlA3ams

    ...it shows annotated ltspice sims of many types of...
  18. Closed: Re: Intrerleave wind transformer on Phase Shift Full Bridge converter?

    Thanks, i thought proximity losses were worse when there were say, multiple layers of windings on top of each other.
  19. Replies
    13
    Views
    556

    Closed: Re: Off-line Power factor correction

    Sorry but you are fixated on “DCM is needed for PFC”…in real terms you can get adequate pfc IN bcm, or ccm, or a combo of dcm and ccm…..take an average mode pfc like using LT1248….that can transition...
  20. Replies
    23
    Views
    921

    Closed: Re: Vicor Bus Converter module

    Hi
    Unfortunately there’s no chance of splitting up the power supplies, ie one per drone motor…so its one single big power supply. That’s what’s been decreed…

    To re-iterate, The power supply has ...
  21. Replies
    23
    Views
    921

    Closed: Re: Vicor Bus Converter module

    Its a power supply for a 12kW drone.
    If a primary switch fails, (ie the high side one in the buck(s)) then the drone emergency lands on its reserve battery supply.

    - - - Updated - - -

    Aaah,...
  22. Closed: Re: Silicon carbide FETs best for Phase shift full bridge?

    Thanks, thats what i was fearing....and gauranteeing ZVS over all load range, and all transients, is going to be tricky.
  23. Replies
    23
    Views
    921

    Closed: Re: Vicor Bus Converter module

    Height isnt a problem no.
    I dont know why Vicor, but partly because their guys like vicor and they used it on a much lower power drone.

    Also, since there is no requirement for isolation, what...
  24. Replies
    23
    Views
    921

    Closed: Re: Vicor Bus Converter module

    The cable length is 320metres

    Thanks, i'll recheck this, it was told that it would be one motor, but i cant see how that works....it would then need a tail motor like a helicopter?


    Would you...
  25. Replies
    23
    Views
    921

    Closed: Re: Vicor Bus Converter module

    Thanks,

    A contractor has now given us a Block diagram for a power supply for a single_motor_drone power supply using vicor modules……

    Its 50V at 240Amps to the motor/Drive.

    This ultimately...
Results 1 to 25 of 500
Page 1 of 20 1 2 3 4