Capacitors

Discussion in 'The Projects Forum' started by harman65, Dec 24, 2012.

1. harman65 Thread Starter New Member

Nov 30, 2012
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i am using a solar panel of 6v,200mA current and i want to run a 12v,500mA motor from it by first storing energy in a capacitor and the using that energy to run the motor? how can i do that? can anybody help me with the circuitary

2. R!f@@ AAC Fanatic!

Apr 2, 2009
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I don't think a single capacitor would do tht.

Besides take a look at the values. You wanna drive a greater load than the Supply.
A capacitor can only supply Power for a real short period unless it is rated in Farads. And tht solar panel cannot charge a capacitor to your needed voltage without a Boost converter.

But still your panel is not suited for Boost converter performance. You need a 12V panel of around at least 1 amp capability.

3. ScottWang Moderator

Aug 23, 2012
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solar panel 6V/200mA → capacitor → 12v/500mA motor

1.2W Power → Cap → 6W Motor

How nice, if you using the battery probably it's better.

Could you tell us why you want to use the capacitor to be the power source for motor?

4. spinnaker AAC Fanatic!

Oct 29, 2009
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That would be one giant capacitor. Even a super capacitor would only tun that motor more than a few minutes once the sun went down.

Plus you have a 6v panel and a 12V motor. You are going to need a buck booster putting even more requirements on what that cap will have to provide.

What's wrong with a battery?

5. ErnieM AAC Fanatic!

Apr 24, 2011
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I see where you are coming from, it makes sense to get the large starting current from a capacitor, then let the panel supply the long term (and lower) current.

My first question is have you tried this motor in place with a 500 mA source? I say the current as panels producer current not voltage.

Next... someone posted a link to just such a circuit in the past few days. I can't see it so I hope they wander by and repost it.

6. harman65 Thread Starter New Member

Nov 30, 2012
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actually i am making a solar train for a competition so cant use batteries and i can only use some kind of storage mechanisms , also i want to pull a load i.e weight of my train will be around 400gms ..... also if you could tell me some other motor which can pull this load and also is there any better storage mechanism. we have to stop the train at some stop station where there is no light i.e. they are covered like a box so i am planning to use LDR for that (if i use storage mechanism)...........pls help

7. harman65 Thread Starter New Member

Nov 30, 2012
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also there will be six 500w halogens on the track which will provide energy to the panel

8. spinnaker AAC Fanatic!

Oct 29, 2009
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Look into Super Capacitors.

I think your motor selection is going to be critical.

As mentioned, you are going to need a buck boost regulator if you stick with that motor or those panels. If you could put 2 or better 3 in series then all that would be is a regular buck regulator.

There are off the shelf regulators for both types to be found on ebay.

And please use capitals at the beginning of your sentences and only one period. It makes your posts so much easier to read. Thanks.

9. harman65 Thread Starter New Member

Nov 30, 2012
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What will be the size of buck booster and its cost?

10. spinnaker AAC Fanatic!

Oct 29, 2009
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It is Christian holiday Christmas so a lot of people that are far more expert than me are with their families. Hopefully they will be able to help you more than me when they return,

But you can look for boost converters on ebay.

http://www.ebay.com/sch/?_nkw=boost convertor&clk_rvr_id=430724262381

I did a quick look and did not see any for 6-12V but that does not mean they do not exist.

As I said it would be easier if you can find a 6V motor or a 12V panel or use 2 6V panels in series.

Nov 30, 2012
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Thanks!!!!!!

12. spinnaker AAC Fanatic!

Oct 29, 2009
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You can of course build a boost convertor. There are lots of chips out there that are pretty easy to use. The MC4063 is very old and not the most efficient chip out there but it is very versatile and has been around so long there are lots of circuits for it. It can be a step up (boost) regulator or a step down regulator.

Nov 30, 2012
16
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