Need a help ( DC-DC converter with solar cell as power supply )

Discussion in 'General Electronics Chat' started by sa7her, Oct 19, 2010.

  1. sa7her

    Thread Starter New Member

    Oct 19, 2010
    Hi every one,

    This is my first post here and sure not the last :D. Im now on third year university and Im planning to build a DC-DC converter with solar cell charger as a Vi for the converter. I did my resarch about solar cell and sadly I find it dificult :( to draw a circuit that make the solar cell as a power supply for my converter . I want any body to help me and give the advise how to do it and if any one have circuit ( scmh ) for the converter with the solar I will be thankfull.

    If it not possible can any one give me the circuit for the DC-DC converter at first and later I will find the soultion for the solar :D. I looked for a circuit on the internet and most of them was simple and not good enough for a third year university :D. I know there an expert here and maybe they will lough on me for my question :( but instead of lughing can they help me and I will be thanckfull :D.

    Finaly sorry for my english if it is not clear

  2. sa7her

    Thread Starter New Member

    Oct 19, 2010

    Is it so hard
  3. Kermit2

    AAC Fanatic!

    Feb 5, 2010
    There are as many DC to Dc converter circuits as there are different Dc voltage levels in use in the world.

    We need a little more info to help you. What voltage do you have and what voltage would you like to change it to. How many amps of current are you needing?

    There are several IC chips that are made just for DC/Dc conversion and need very few external components to complete. If you need large amperage currents then the circuit will get more complex and hard to build.
  4. beenthere

    Retired Moderator

    Apr 20, 2004
    You English is clear enough. We do need the specifications on the solar cell, though, as well as the voltage and current the DC - DC converter should be able to provide.
  5. russpatterson


    Feb 1, 2010
  6. sa7her

    Thread Starter New Member

    Oct 19, 2010
    Thanks foy your replays

    Im planning to do 12V to 48 DC-DC Converter like this one on youtube

    I will think about the solar cell later.

    can anyone give me any advise
  7. sa7her

    Thread Starter New Member

    Oct 19, 2010
    Also what you think about this circuit on page 5

    Do you think it will be usefull and is it possible later to add a solar cell to be power supply ( Vi )

    waiting your replays experts ^_^
  8. marshallf3

    Well-Known Member

    Jul 26, 2010
    So long as you understand that solar cells are mainly used to charge batteries which are later called upon to generate some extra power. Solar cells alone don't put out enough power to effectively operate anything but very small devices directly - unless of course you've got an entire field full of them.
  9. sa7her

    Thread Starter New Member

    Oct 19, 2010
  10. SgtWookie


    Jul 17, 2007
    If you will be charging 12v sealed lead-acid batteries (SLA) then you will need approximately 14v to 14.5v per battery in series during the bulk charge phase, and 13.65v per battery for the float charge phase.

    If you have 4 batteries in series, then you will need four times those voltages.

    Boosting 12v to 56v-58v means that you will need roughly 5x the current at 12v than you will get out at 56v-58v; and this does not include losses due to the efficiency (or lack thereof) of the power converter. 92% efficiency is about the best you could hope for. 85% is more likely, if you are very careful in your design.

    Without knowing what your battery specifications and solar cell specifications are, it would just be a waste of time trying to come up with a circuit for you.