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
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.