Amplifying current/voltage

Discussion in 'The Projects Forum' started by harman65, Nov 30, 2012.

  1. harman65

    Thread Starter New Member

    Nov 30, 2012
    16
    0
    I AM HAVING SOLAR PANELS OF FOLLOWING SPECS
    6V 150mA & 1V 450mA
    i want to run a 6v DC MOTOR??
    is 150mA enough??
    how an i step up current??
    ALTERNATIVELY, If stepping up voltage in the other panel is a good idea? if yes how?
     
  2. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    4,770
    970
    You didn't provide the specs on the motor (as far as current requirements) so we OBVIOUSLY can't answer question #1
    You can't "magically" increase current if its not there in the first place.
    Ohms law...
    6V x .15A = .9 Watts (so you have .9 watts to work with)
    If current goes up..voltage goes down.
     
    harman65 likes this.
  3. wayneh

    Expert

    Sep 9, 2010
    12,127
    3,048
    Your panel may or may not supply 150mA at 6V. It's more likely that the two specifications are the open circuit (no load) voltage of 6V and the shorted (no voltage) current maximum of 150mA. So the panel in real service might deliver 30mA at 5V, or something like that; a combination of voltage and current both less than those quoted figures.

    Whether that will run your motor depends on the details of the motor. Both of your panels in series together might not be enough to run that motor, no matter what.

    You cannot design for stepping up or down current or voltage until you know what the target is, 6V and how many milliamps. No matter what, you lose power any time you need to alter that power by stepping it up or down or converting it in any way.
     
    harman65 likes this.
  4. harman65

    Thread Starter New Member

    Nov 30, 2012
    16
    0
    sorry my bad
    motor specs are 6v,300mA
    actually my project is to make a solar train, so if u have any better ideas please share!!! thanks
     
  5. harman65

    Thread Starter New Member

    Nov 30, 2012
    16
    0
    motor specs are 6v,300mA
     
  6. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    7,392
    1,605
    If you put the 2 cells in series you would get 7 volts (voltage adds) at 150 mA (limited by the smaller current). If you put them in parallel you get 1V at 600 mA (current adds, voltage clamped to the lower) (and this assumes they have internal blocking diodes).

    Neither combo is 6V 600mA but may be enough to run the train at something less then flat out full speed. So you have an experiment to try.
     
    harman65 likes this.
  7. harman65

    Thread Starter New Member

    Nov 30, 2012
    16
    0
    sir
    can anything else be included in the circuit i.e. between the solar panel and the motor to get the requisite voltage and current??.....some current amplifiers etc..???
     
  8. wayneh

    Expert

    Sep 9, 2010
    12,127
    3,048
    No, the fundamental problem is that the power output of your panels, however combined, is less than the power spec for your motor. Power = voltage x current, W = V•A. You can't get more for the motor than the panels provide.

    Circuitry of any kind can only make that worse, can only waste some of the precious power.

    The only hope would be that some circuit would optimize the matching of the power source to the load, and thereby allow it to operate (poorly) at that narrow optimum. It's possible in theory, but IMHO that would be a lot of work for little or, most likely, no payoff. Choose a different motor or get more PV panels.

    Or experiment carefully. Maybe your motor will operate "OK" with either the series or parallel combination of your panels. There's only two options, so it would be easy to try. Be sure to use full direct sun to test.

    You can store energy over time into a battery, for a brief run of the motor, if that's interesting.
     
  9. harman65

    Thread Starter New Member

    Nov 30, 2012
    16
    0
    SIR
    i am participating in a competition where there are many restrictions on size of panel and use of batteries is prohibited.....another thing i want to ask that a 3v,150mA DC motor will be able to move a load of at least 500gm with the 6v,150mA panel
     
  10. Audioguru

    New Member

    Dec 20, 2007
    9,411
    896
    A motor with flea power can move a very heavy load. If its GEARS or pulleys allow the load to move slowly then the torque is increased.

    I have a couple of RC helicopters. The tiny motor spins very fast near maximum speed for near maximum power and the gears drive the blades slower but with higher torque.
    It can lift itself easily including the radio receiver, gyros, servos and battery.
     
  11. harman65

    Thread Starter New Member

    Nov 30, 2012
    16
    0
    sir i am unable to understand your answer. also what are the specs of your motor?
     
  12. Audioguru

    New Member

    Dec 20, 2007
    9,411
    896
    The motors in my helicopters do not have spec's but they are very small and lightweight.
    It is the gears that increase the power to move the weight.

    If your train weighs 500 grams then select gears to allow the motor to move it. The gear ratio determines the weight that can be moved and the speed. High torque but slow speed. Low torque but high speed. Just like a bicycle or car.
     
Loading...