3 phase Voltage Doubler for Chinese WG

[spacejunk]

G'Day,

I built this voltage doubler to charge 24V batts from a 12V 200W Chinese WG.

So at full noise (refer to comments below), it was charging 30V (24V) at 10A which is the same as its rated 12V at 300W max. Diodes need to be rated above 10A/35V, I used Dual Schotkey diodes in a TO-220 package rated at 15A/45V each diode. These gens generate around 50-60Hz max so large caps were required. I had these 100,000uF laying around but they are expensive new. If your WG develops higher Freq output, you can get away with lower value caps. And I calculated that 10,000uF caps would have been fine.

Efficiency is almost 100% ignoring diode drops, much more efficient than a Flyback type inductive doubler. It would be a good idea to protect the Schotkeys against transient pulses also.

It took me a while to build the cct, then the WG flew apart in the first wind at max rating. I found mine to be EXTREMELY noisy and was unable to sleep without earplugs in even with the WG installed over 160m away from my brick house in a modeate wind. I dont recommend these "Cheap" Chinese generators.

Remember " The poor man pays twice ".

 

[Ungrounded Lightning Rod]

C4 seems redundant.

[fungus]

C4 seems to be a smoothing capacitor, not needed for charging batteries but useful in other situations.

[hvirtane]

from a 12V 200W Chinese WG

What make was it?

- Hannu

[dinges]

I'd ask, what brand, type and what price; where bought/what supplier. Did they follow up on your complaints/guarantee claim. Name & shame, so to speak. Can't have too much information. Esp. with respect to junk. Leave the politeness & political correctness to the politicians. Just the facts, ma'am

Peter.

[DanB]

My thought....

I dont care 'where' it was made...  there is some really good stuff and some really bright people all over the world.

If you don't like the machine and are advising us against such machines, we need to know 'who' made it. China currently is making some of the best (and worst) stuff in the world.   I've seen some wind turbines built in China that seemed very well made, very honestly rated etc...

If there is a problematic company - you should be more specific.

I can name a couple american ones that I think suck...

SW Windpower 'Air'

Hydrogen appliances

WindGenZen (they probably make some great stuff but the website is full of hype and unworkable ideas)

and lots lots more.  Don't pick on China - it's a big place full of good folks I think.

The problem comes in when marketing becomes more important than building a good machine.

[Ungrounded Lightning Rod]

NOW I notice that C4 is labled "OPTIONA(L)"  B-(

[hvirtane]

Don't pick on China - it's a big place full of good folks I think.

I agree. The best hand tools I've bought were

made in China. There are good and bad products

coming from every country in the world. I still remember the time, when Japanese products such as cars were considered to be of bad quality. At present the quality of Japanese cars such as Toyota, Nissan and Mazda is considered to be the best in almost every test made in Europe.

- Hannu

[bj]

     Dan--I agree.  There is a lot of junk out there, but it  dosen't

have a nationality.  Maybe there is enough room on this fine board

for a "this is junk" section?  Just a 4 in the morning thought.

     Love your postings, It gives me reasons to get up in the mornings.

     Thanks  bj

[ghurd]

Yes.

China makes what companies order.

Order a 24" bolt cutter with a retail value of 99 cents and thats what they make.

I see the problem as many companies go to China to save every penny they can, including cutting every corner.

G-

[(unknown)]

There should be a diode across the capacitors so they do not reverse polarity, so it bypasses the capacitors if they discharge before the generator changes polarity, it'll protect the capacitors from damage, this setup can be used for a DC boost at the lower wind speeds also on a 24v gen on a 24v battery bank.

[spacejunk]

Thanks Romster,

I see your point re reverse polarity protection of the Caps. In this situation they are not really needed as a Wind Gen usually increases its gen volts "slowly" thus the Caps wont be subjected to the instantanious reverse polarity that one would see if the cct was attached / switched to a fixed AC source. It would be good practice tho'.

Also, the Schotky Diodes tend not to be very robust, from practical experience, I recommend using standard rectifier diodes of a higher reverse voltage. These will be less efficient and generate about twice as much heat, but may be more practical. The cct can also be used to double 24V to 48V etc (minus diode Vdrop) with Cap Voltage increased.

I'd be interested in comments from anyone that has built this doubler?

'Wait long by the river...The bodies of your enemies will float by"