Micro 12v Generator Project

skipper_stu said:
Tim
lots of bikes have 50cc 2 stroke engines, quite a lot liquid cooled, where is this leading? I think if we were to really consider this seriously then a diesel is the only way to go, saves all the faff with differing fuels and also gives a robustness to the thing, thats why all the Farrymans etc go this way.. Dont forget they use watercooling of the genny bit because the soundproofing prevents a good flow of air to cool it.
Stu
This looks good http://www.youtube.com/watch?v=pm4WfH6v004
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the smallest diesel (i can find) is a Yanmar L40, 4hp ish, but its 22kg +electric start kit + alternator, frame, mounts etc, which takes it way over 30+kg, which is miles away from the original title of "Micro 12v Generator" which should be under 8kg, strangely, if i did go that way that would be very much into the "re-inventing the wheel" area, as they really do already exist....(30kg+ diesel gennys that is)

The original project (just as a reminder) came from the fact that i already have an EU1000i, and a Kipor IG2000 (for 2 different uses, but tried both on the boat) and they dont offer what i wanted, that is, something that i can use when say rafted, say at Bembridge, at anytime i fancy (middle of night?) that will dish out a decent amount of 12v amps and be "silent" I have an inverter so not that fussed about 240v

Long term i would like it to be installed somewhere, so it doesnt need any moving around, just press a button and start it up.

Not going to happed with a 30kg+ lump, would really need to getter a bigger boat.

Diesel would be perfect, but we carry gasoline anyway for the tender and at <200g/hour dont think it will be using huge amounts.

If anyone can find me say a 2hp diesel that is 10kg or so, i would buy one right now and use that.
 
This is just an amazing thread, I am as facinated by the protagonists involved, as the project. Hats off to Matt for persevering both with the tecnical issues and keeping us all posted on the progress.
As far as i am concerned it would not matter to me if he was in fact re inventing the wheel. In all aspects of our society we are so used to just picking something off the shelf that someone else has produced. And putting up with the inevitable compromise that that involves. We make do with it because we neither have the ability, or the inclination to do something about it ourselves.

Matt has decided on a project for whatever reason, availability of major components, curiosity, thirst for knowladge, pure enjoyment. he has also decided that others on the forum would be interested ( and we are) I just cant understand the negative "contributors". what is the point?

At the end of his project he will have something that suits his purpose,he will have the satisfaction of producing it himself.
 
mattnj said:
Thought some people may be interested in my micro generator project....

Plan is for a tiny, light 12v generator capable of a decent output 20amps min, hopefully 40amps+, super quiet....light and small, with a simple diode mod on the regulator to boost the output voltage.

Starting point is a Honda WX10 water pump based on a GX25 Honda petrol 4 stroke, which is 25cc and 1hp ish, they use about 250ml of fuel per hour.

Will be directly coupled to a Denso Lightweight Motorsport Alternator (55amp max)

The standard engine is air cooled, the first version will stay air cooled, but i have fabriated a raw water cooled exhaust manifold with a 12v pump so the exhaust can be run via a longer output pipe over the side of the boat and things should be much quieter and take most of the heat away, the 12v pump runs when the alternator is producing charge, and is a small submersible unit that you chuck over the side. The idea is to make the whole thing water cooled later on, so it can go in a box, for now, it will need to stay ourside and exposed for cooling.

The whole unit is under 8kg at the moment and very small...

First pictures to give an idea, mounting the alternator today, will update as i go.
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I did try making just this about 10years ago when I worked at a boat yard. It was for a solo round Britain sailor who wanted minimum weight and size.

It was much more difficult than expected:
Connecting the alternator to the engine reliably was difficult due to alignment and vibration through the engine shaft.
Trying to charge a battery that was well down was difficult because the alternator tries to produce its full output and this stalled the engine immedialtely the load was connected.

Hence, you need a way of limiting the alternator output to say 20 amps, ideally with a 'soft start' feature. In the end I came to the conclusion that a Clarke 700watt Generator which you can now pickup from under £100, with a 20amp mains battery charger plugged into it was simpler.

ian
 
ianj99 said:
I did try making just this about 10years ago when I worked at a boat yard. It was for a solo round Britain sailor who wanted minimum weight and size.

It was much more difficult than expected:
Connecting the alternator to the engine reliably was difficult due to alignment and vibration through the engine shaft.
Trying to charge a battery that was well down was difficult because the alternator tries to produce its full output and this stalled the engine immedialtely the load was connected.

Hence, you need a way of limiting the alternator output to say 20 amps, ideally with a 'soft start' feature. In the end I came to the conclusion that a Clarke 700watt Generator which you can now pickup from under £100, with a 20amp mains battery charger plugged into it was simpler.

ian
Click to expand...
Thank goodness Im not the only one, when I dared to air similar views I was name called, but there we go. Be prepared!
Stu
 
ianj99 said:
I did try making just this about 10years ago when I worked at a boat yard. It was for a solo round Britain sailor who wanted minimum weight and size.

It was much more difficult than expected:
Connecting the alternator to the engine reliably was difficult due to alignment and vibration through the engine shaft.
Trying to charge a battery that was well down was difficult because the alternator tries to produce its full output and this stalled the engine immedialtely the load was connected.

Hence, you need a way of limiting the alternator output to say 20 amps, ideally with a 'soft start' feature. In the end I came to the conclusion that a Clarke 700watt Generator which you can now pickup from under £100, with a 20amp mains battery charger plugged into it was simpler.

ian
Click to expand...
yep, i have most of those problems, but overcome the all (nearly i hope)
The alignment is easy enough as long as it is measured/machined correctly, but took me a failed coupling to realised hope good it needs to be.

Also had the same problem with engine stalling so now have a fully adjustable and programmable alternator regulator, which does "soft start" and also backs off the charge rate, as soon as it sense the rpm drop (whilst adding throttle)

a bought genny is "simpler" for sure, they key features for me is the silent running, boxed, (water cooling) and auto start, which i couldnt find on a small unit.

Making good progress, will stick a video up of the "ecu" running later today hopefully.

well done Stu, i can tell you are just sitting there waiting all the time for some more "told you so" "i know it all" action...very helpful, everyone here must be thinking "wow that Stu's a nice helpful friendly chap"
It is clear that you want me to fail, strangly that is encouraging me more to keep going until its all sorted.
 
mattnj said:
yep, i have most of those problems, but overcome the all (nearly i hope)
The alignment is easy enough as long as it is measured/machined correctly, but took me a failed coupling to realised hope good it needs to be.

Also had the same problem with engine stalling so now have a fully adjustable and programmable alternator regulator, which does "soft start" and also backs off the charge rate, as soon as it sense the rpm drop (whilst adding throttle)

a bought genny is "simpler" for sure, they key features for me is the silent running, boxed, (water cooling) and auto start, which i couldnt find on a small unit.

Making good progress, will stick a video up of the "ecu" running later today hopefully.

well done Stu, i can tell you are just sitting there waiting all the time for some more "told you so" "i know it all" action...very helpful, everyone here must be thinking "wow that Stu's a nice helpful friendly chap"
It is clear that you want me to fail, strangly that is encouraging me more to keep going until its all sorted.
Click to expand...

Yes, keep at it, the problems are not insurmountable (the 'yard didn't have a machine shop otherwise we'd have cracked the mounting / coupling problem and the rest would have been easy). I hated giving up on it but time is money and the boss didn't see the bigger picture...

In fact I think there is a market for a small, light, 20amp petrol battery charger though it would need to be made in the Far East to keep the price down. With the addition of a cheap inverter mains power would also be available.
Ian
 
here you go to all interested, a video of the "ecu" connected up and running the engine, water pump, with speed hold and adjustment, I have removed the alternator whilst i work on the new coupling (will be much closer to engine and hence make unit smaller) so it doesnt hold speed so well without it, does a bit too much "hunting".

Easy to change all the parameters, engine start throttle, max throtte, min throttle, hold rpm, rpm variation allowance etc etc all on the software on the laptop, which you then upload to the microcontroller.

You can see the red LEDs flashing LH one is overspeed and adjusting, RH one is underspeed an adjusting, both off means it is happy with the speed and doing nothing.

Its difficult to tell how quiet it is, but it is very (compared to the standard muffler) the phone it only about 6" from the engine when filming.

Next step it is complete the alternator mount, then it can be tested (and debugged) with the alternator controller as part of the software. The alternator is fully adjustable in 255 steps, it is programmed to increment up a step every 0.5 seconds, until it senses the engine speed drop, then it hold the charge rate. If the engine speed drops more than a specified amount, the charge rate is backed off a bit. It runs in parallel with the engine hold software, so you can pick any rpm you like, either preset (low, med, high) or adjust it with a pot, then alternator then dishes out the max charge it can for that engine speed.

http://www.youtube.com/watch?v=FirTtvFxNDI

I have also been working on the cooling system a bit, it now has microbore copper pipe soldered onto a copper block that is bolted to the head, and fed from the same water supply, which takes a load more of the heat away. It all looks a compete mess at the moment, but is coming along nicely!
 
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Great stuff!

Unfortunately I can't view the video whilst at work, I'll enjoy watching that later though.

One question I did have, have you or how have you managed the cold starting scenario? Have you managed to sort out auto choke as well? I've no doubt you've covered it somehow or other, I'm just curious as to how!

The other thought I had ref some of the recent posts about similar things being tried in the past.

I think people sometimes forget that although they tried things years ago, the incredible electronic advances of the last few years make doing some control processes quite achievable now, that were far too complicated even 10 years ago. So it's OK saying "I tried it and it doesn't work" etc but the technology and facilities that are both available and affordable now, make some projects a far more realistic proposition than they might have been previously.

If we all just accepted that things couldn't be improved, the word progress wouldn't exist...

No offence intended to those who have tried it before, good on them for trying too. Persistence can pay off!
 
Trundlebug said:
Great stuff!

Unfortunately I can't view the video whilst at work, I'll enjoy watching that later though.

One question I did have, have you or how have you managed the cold starting scenario? Have you managed to sort out auto choke as well? I've no doubt you've covered it somehow or other, I'm just curious as to how!

The other thought I had ref some of the recent posts about similar things being tried in the past.

I think people sometimes forget that although they tried things years ago, the incredible electronic advances of the last few years make doing some control processes quite achievable now, that were far too complicated even 10 years ago. So it's OK saying "I tried it and it doesn't work" etc but the technology and facilities that are both available and affordable now, make some projects a far more realistic proposition than they might have been previously.

If we all just accepted that things couldn't be improved, the word progress wouldn't exist...

No offence intended to those who have tried it before, good on them for trying too. Persistence can pay off!
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hi, dont get too excited about the video, its a big rubbish but gives you an idea...try to keep all updated as it has generated so much interest.

Doesnt need any cold start, i have never used the choke ever, it starts so easily, and will be even easier when the electric start goes on, i guess it may need something done, but wouldnt take a minute to slap another servo on there, the one is just bought from my local model shop was £2.99!

I completely agree, PIC microcontrollers and the internet just didnt exist 10 or so years ago, you can do so much more these days, so much more info available too and the click of a button.

The though of making a microcontoller 10years ago to do all this lot a while back would be a nightmare, now its an afternoons work (if you know what you are doing)
 
it works!

modified the coupling and wired in the adjustable alternator regulator tonight, the first test worked perfectly, fully adjustable output and the servo holds the engine speed.
had to give up as the grubscrew on the coupling flew out, but will post some more info tomorrow, i need some loctite!

think i may look into upgrading to the 1.5hp engine too so i can get more output, think the gx25 maybe just a bit underpowered, more amps please!
 
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mikefleetwood said:
Have you got a flexible coupling? Probably a good idea, and fairly cheap.

Don't go buying a bigger engine - you will get all sorts of told-you-so comments:D
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yes, i'm sure i will there is an expert in "i told you so" on here.......the main reason is that i also fancy having my WX10 pump back, and found these available, similar size and weight, same "micro generator" concept, just a decent hike in power output, so i can run it slower and quieter for the same output, or have more output at max rpm:-

http://www.seddondirect.co.uk/productDetails.asp?productID=371
 
So when all is complete are you going to supply us with a list of parts so we can get cracking on ours?
You can sell us an electronics kit so we can develop our circuit board building skills?
Will we then have a good lightweight charger that doubles as a pump?
Can you sumerise why this item ( properly developed and marketed) will be superior to buying a cheapo genny (Sub 1KW and sub £100)
One reson for me buying the cheapo genny was emergency charging the starter battery!
Congratulations by the way!!
 
pcatterall said:
So when all is complete are you going to supply us with a list of parts so we can get cracking on ours?
You can sell us an electronics kit so we can develop our circuit board building skills?
Will we then have a good lightweight charger that doubles as a pump?
Can you sumerise why this item ( properly developed and marketed) will be superior to buying a cheapo genny (Sub 1KW and sub £100)
One reson for me buying the cheapo genny was emergency charging the starter battery!
Congratulations by the way!!
Click to expand...
Peter
http://www.energymatters.com.au/generators-honda-c-159_272.html
About £600ish, they look like good pro jobs.
Ive got a side valve Honda gennie, 1.2kw, I considered taking the gennie off and fitting an alternator and fitting it in the sugarscoop as a permanent job, it is governed so once the revs are set the load regulates the speed, it is powerfull enough to take the full load of the alternator so no need for a soft start, but in the end decided that my £239 SDMO genny, was light enough, quiet enough and powerful enough to run my onboard charger plus other stuff. Not in the spirit of PBO I know, but life is getting shorter and Ive got other things to fiddle with! SWMBO also likes toast in the morning and the SDMO copes admirably with the toaster so a win win situation, toast for Mam and the batteries get charged!
Stu
 
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