Boost Converter 4.5VDC-330VDC / Electromagnetic Projectile Accelerators / Forums

Forums

4hv.org :: Forums :: Electromagnetic Projectile Accelerators

« Previous topic | Next topic »

Boost Converter 4.5VDC-330VDC

first previous 3 4 5 6 next last

Move Thread

LAN_403

Killa-X

Sat Sept 20 2008, 02:08PM

Registered Member #1643 Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039

Ya, not sure. All I know from a single spike test is that every time it spiked over my multimeters 500V limit.

Apparently they are called Yellow Medium Inverters. And can run 4, 6, and 8 watt flourecent lights. Found a Tutorial on them, same size and stuff, running a larger 24 inch one blacklight.

j.azz

Sat Sept 20 2008, 02:58PM

Registered Member #888 Joined: Tue Jul 10 2007, 06:52PM
Location: Hannover, Germany
Posts: 40

Well, the boost converter's voltage gain is limited. By it's own components not being mathematical ideal.
They work with self induction. A current pulse creates a magnetic field in/around the coil which, when the current drops collapses, inducing voltage in the coil. *theoretically*, without load this voltage should be infinite. But as there cannot be an energy jump, the resistance of the coil and any other component involved will slow the collapsing speed of the magnetic field and thus be limiting current and voltage you get.

uzzors2k

Sat Sept 20 2008, 07:05PM

Registered Member #95 Joined: Thu Feb 09 2006, 04:57PM
Location: Norway
Posts: 1308

Uzzors wrote ...

Theoretically the maximum voltage from a boost converter is infinite. But real components have limitations which will keep it down.

Agreed.

voyagerscout

Mon Sept 29 2008, 04:06PM

Registered Member #1696 Joined: Sat Sept 13 2008, 06:01PM
Location:
Posts: 21

I've build the converter, and it works great:)
it charges my capacitors 21,4 times faster than the converter inside a disposible camera:)
but, the variable resistor (I know the word for that in English, sorry) doesn't effect the voltage. it just keeps charging :S
and the led doesn't burn when the capacitors are charged to a certain voltage.
what am I doing wrong?

Killa-X

Mon Sept 29 2008, 04:42PM

Registered Member #1643 Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039

voyagerscout wrote ...

I've build the converter, and it works great:)
it charges my capacitors 21,4 times faster than the converter inside a disposible camera:)
but, the variable resistor (I know the word for that in English, sorry) doesn't effect the voltage. it just keeps charging :S
and the led doesn't burn when the capacitors are charged to a certain voltage.
what am I doing wrong?

Your lucky. I never see my led go on, it hits 30 volts and goes very slow. Testing it on a 9V battery, and I don't know whats wrong :(
8V over the + - of the 555, like 4V in the 10nf capacitors, 2 over the 1nf. Why :( Cant pass 30V, doubled checked the paths, not resistors yet, and the pot i checked. :(

big5824

Mon Sept 29 2008, 06:08PM

Registered Member #1687 Joined: Tue Sept 09 2008, 08:47PM
Location: UK, Darlington
Posts: 240

i got the same problem when i was designing it on a circuit simulator....i thought it was just a bug but i guess its a real problem

voyagerscout

Mon Sept 29 2008, 06:29PM

Registered Member #1696 Joined: Sat Sept 13 2008, 06:01PM
Location:
Posts: 21

I tried a 9 v battery to, it charged to 45 volt, and stopped:P
but, I thought, maby 9 V isn't enough to make the 555 chip work, or something like that
I hooked the boost converter up to a 12V adapter, and it worked:)
my advice is, try an adapter ;)

Kipmans

Mon Sept 29 2008, 07:40PM

Registered Member #91 Joined: Thu Feb 09 2006, 03:03PM
Location: The Netherlands
Posts: 45

9 V is probably enough to get the circuit working, but the current you can draw from a 9 V battery before the voltage drops significantly is very limited.

uzzors2k

Mon Sept 29 2008, 08:51PM

Registered Member #95 Joined: Thu Feb 09 2006, 04:57PM
Location: Norway
Posts: 1308

Kipmans wrote ...

9 V is probably enough to get the circuit working, but the current you can draw from a 9 V battery before the voltage drops significantly is very limited.

Dead-on. There's a reason I set the voltage to 12V despite the circuit being battery operated, after all it draws around 3A. 9V alkaline batteries can only supply around 0.5Ahours, which means 3A for 10mins. And that's not even taking the internal resistance of the battery into account.

Angry_Llama

Mon Sept 29 2008, 09:46PM

Registered Member #1669 Joined: Sun Aug 31 2008, 02:33AM
Location: 127.0.0.1
Posts: 13

I've got some extra 360 power supplies, basically re-purposed ATX ones. It outputs 12V at 16A, think I could use it here without damage?

first previous 3 4 5 6 next last

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob