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Solutions Knowledge Base

Posted: Mon, 04 Jan 2010, 05:16
by Squiggles
I reckon a really useful resource would be an organised, indexed, search-able knowledge base. One that is built up with real solutions from owners/builders experience.

Things like.
1. How to make airbags work in an EV conversion.
2. What drive ratio works best with my ???kg EV with a particular motor.
3. Who makes/sells the best flexible high current electrical cables.
4. How much weight was removed with a particular ICEectomy.

Anything at all that helps a potential converter make decisions or answer problems.


I know lots of really cool things have been presented on this forum, it is not always easy to find them when you need them though.

Any database gurus in our community?

Solutions Knowledge Base

Posted: Mon, 04 Jan 2010, 07:56
by Thalass
Do you mean a wiki of EV conversion knowledge in Australia? Not a bad idea, I suppose.

Solutions Knowledge Base

Posted: Mon, 04 Jan 2010, 13:22
by Squiggles
I don't know....what is a wiki? Sounds like a little basket you put your groceries in.

Solutions Knowledge Base

Posted: Mon, 04 Jan 2010, 16:52
by Thalass
hahaha!

Wikipedia is a wiki. The wikimedia foundation makes the software that runs the site available to the public for free. Assuming you have access to the server you can install and run a website in much the same manner. I have one on my computer to manage my (many) projects.

Solutions Knowledge Base

Posted: Tue, 05 Jan 2010, 00:54
by Richo
There was some discussion before.
But I can't remember what the outcome was.
I think it was going to be a problem with too many differences in opinions.
ie no one right solution

Why search for an answer that may not exist yet.
for example in Q2 about drive ratio's.
That would imply that one type of car has been converted a number of times in slightly different configurations.
Which has not really happened yet.
But then each person may have different requirements.
So you'll end up with with say 3 cars with 3 people saying thier ratio is the best.
None are wrong just each suits them.

Then Q3 where the answer may vary regularly depending on suppliers and economics.
So would be a pain to maintain.

But I do agree a wiki could be a step in the right direction.
Until then best just to ask and see what people come up with.

Solutions Knowledge Base

Posted: Fri, 15 Jan 2010, 02:44
by Sparky Brother
The Panacea you are looking for Richo is called a Common sense.

I was the first(ages ago) to raise the question about an organized database to help people less hard headed than some of us (count me for one) Image to adopt some ideas or part of them or even take them further.

I strongly disagree that the human progress happens due to a nicely organized data base in which every Idea was 100% tested and safe for use. I think that is called "Utopia"

I don`t want to be nasty but hmm, I think that the outcome this time will be pretty much the same.


Solutions Knowledge Base

Posted: Thu, 21 Jan 2010, 18:55
by PlanB
I think the idea has merit squiggles. If it was no more than a list of hyperlinks to some interesting sites it could be worthwhile for those of us with just a toe dipped in the great DIYev ocean wondering what to do next (see my 'getting-of-wisdom' post). Links could be organised by category (controllers, motors, battery chargers, MX5 conversions)?

Solutions Knowledge Base

Posted: Fri, 22 Jan 2010, 05:59
by Richo
Sparky Brother wrote: The Panacea you are looking for Richo is called a Common sense.

You must have me confused with someone else. Image
I'm not looking for anything. Image
Sparky Brother wrote: I strongly disagree that the human progress happens due to a nicely organized data base
True but it does stop some people from wasting thier time.
Sparky Brother wrote: I think that the outcome this time will be pretty much the same.

yep nothing Image


Solutions Knowledge Base

Posted: Sat, 23 Jan 2010, 02:11
by Sparky Brother
Wow! It must feel pretty empty if one is not looking for "anything"

As for people wasting their time I would just quote Volter`s words;
"I disagree with what you say I but would rather die for your right to say it...".

In other words people are entitled to waist their time! What`s so creative about surfing?

Peace Richo Image I just wanted to make certain people to wake up. I still don`t think they will!

Solutions Knowledge Base

Posted: Fri, 28 May 2010, 11:33
by T2
I've been searching for gaps in my knowledge also and it is hard to get people to stay on a topic, with things being so related. We do need a moderated 'sticky' heading for each technical forum that can be referred back to.

There is room for improvement in our delivery of basic concepts. Sometimes I see the noobie asking questions at page 3 that might have been cleared at page 1. A lot of what I know has come after working nearly 40yrs with SCR DC drives and I find if you can master a few basics you can go on to answer a hundred other questions. Concepts can help people do their own reasoning and save a lot of online help.

For instance, when you're riding a bike you quickly discover that a higher gear makes the road easier. Surprisingly, that fact doesn't always translate down to the noobie that it's the same thing for an electric vehicle. A higher ratio gear can reduce the amount of torque and thus relax the requirement for purchasing high current motors and controllers except in the most extreme of cases.

I've seen a couple of direct drive 3.x : 1 and while they have been successful they are still a very expensive way to go and 3600rpm @ 100km/hr won't be in the future of EV's.

Choosing the battery is often the least critical part (to get wrong) but despite being left until last the anachronism is that it is usually the most expensive part of the system. Particularly when the noobie has some unrealistic expectations and has the exuberance to want to throw money at them. What do I need ? is not the question. The real question is What do I want ? No decision can be made until the real 'wants ' are put on the table so we can take a good look at them. Only then can it be determined what the real needs are.

The first shotgun I ever fired was only a 410. I remember the owner saying "this is the most puny gun I have" He then blasted a steel pop can sitting on the fence. We had to go find and examine the can before he would let us fire the gun ourselves. I am reminded of that when I see noobies ask for advice concerning 500v battery packs.

Frankly I don't think anyone should play with 500v before they've first played with a 144v or 96v that's just my opinion. I feel we oughta' be getting that message over on a 'sticky'.   


Solutions Knowledge Base

Posted: Fri, 28 May 2010, 15:27
by Johny
T2 wrote:....and 3600rpm @ 100km/hr won't be in the future of EV's.
Interesting opinion. If my car can not do Tollway/Freeway speeds then it's not really viable (in Melbourne).

Not sure what you are saying in all that T2. This forum is easy to use, has excellent search functions and "newbies" get lots of support.

Anyone I have 'seen' doing a 500-600 Volts conversion so far either has industry experience or is treating the whole thing very carefully and using other peoples experience to stay out of trouble.

Solutions Knowledge Base

Posted: Fri, 28 May 2010, 20:36
by woody
T2 wrote: Frankly I don't think anyone should play with 500v before they've first played with a 144v or 96v that's just my opinion. I feel we oughta' be getting that message over on a 'sticky'.
I agree with your sentiment but not your numbers

I think only <= 48V is considered "safe" by all.

96V should be given the same respect as 500V.

I think a 7.2V system (e.g R/C Tamiya Hornet) was a great starting point for me :-)

Solutions Knowledge Base

Posted: Sat, 29 May 2010, 11:52
by T2
johny you wrote -
      If my car cannot do Tollway/Freeway speeds then it's not really viable
Then what you are doing is really high end, IMO. Please accept the fact that few people have both the mechanicaI and electrical knowledge to reach that level. It's great that you're able to do it today at high efficiency but it comes with a price.

I remember the 70's back when series DC motors were mounted onto automatic 3-spd gearboxes to make freeway speeds achievable. Pick up could be great despite the range not exceeding 30km but after the second pack had been prematurely exhausted, so, unfortunately, was the enthusiasm. I would like to see AEVA not inadvertantly let new EVr's go that path again. I have a sense that the Nissan Leaf, when it comes, may one day claim this level anyway.

OTOH I happen to think a successful EV that can hold 50km/hr minimum can be achievable by a lot of enthusiasts. Without that timely knowledge a few builders have come to realise they have bit off more than they can chew allowing the project to be abandoned. It's somewhat true the saying, that : -
"Experience is what you have - just after you needed it."

In effect we want a Solutions Knowledge Base that will promote good outcomes, and I think that Squiggs & Co. agree with me. Yes there IS a useful search feature here but we need better organising to make it work better Hey, I didn't start this topic !!

I am suggesting :-
We need an AC motors only thread about AC windings, shaft mountings, gearing etc
We need a DC motors only thread about commutators etc same as above

We need an AC controllers thread to discuss new controllers, strategy getting the most out of motor(s) re-configuring motor ccts regen braking.   
We need a DC controllers thread to discuss new controllers, drive strategy getting the most out of motor(s) re-configuring motor ccts regen braking.
Threads for :
Batteries Pb-Acid       BMS,chargers
Batteries LI-Ion, NiMH BMS,chargers

That's SIX threads for starters. There needs to be feedback on their 'stickys' so that they can be continually improved, which infers some way of ownership for updating.
   
I would like to see an AEVA agenda towards high rpm AC drives.

Rewinding as tuarn (ACMOTOR) has done but at even lower voltages to permit packs with fewer but larger cells. Note that Toyota is staying with 201v for their PHEV design.

Threads for new stuff
The Upconverter - idea borrowed from Toyota's Prius - . If you only need HV to be above 100v's while accelerating an upconverter looks to be a good idea, amazingly simple topology using only three significant components. It should be possible to take a Curtis or any other old DC drive which usually contain these parts and modify to suit.

This is a mechanical component not yet available in the EV market. It's an idea I had five years before the IMPACT in 1990 and others probably came up with it even years before that. I mentioned it somewhere here already should be a topic - needs attention of a mill wright:
Planetary gear reducer for mounting on the end frame of the motor
The motor end face would be one wall of the gearbox. The sun gear weould mount directly on the motor shaft. The hollow central part of the gearbox shaped to fit the endface could also mount the internal gear insert. Output shaft/ planetary carrier details TBD.
This "the motor is also the gearbox idea" would have two applications : -
Either Smaller high rpm motor to direct drive a diff
Or      with a larger ratio to direct drive the wheel.   

Well that's it, my time's up

Solutions Knowledge Base

Posted: Sat, 29 May 2010, 20:01
by EVNoob
It is a mistake to think this is a going to be a encyclopedia of how to make EV's, it will just be a wiki of solutions and their pro's and con's.

An over time it will build up to a point where we know (from observation) what works and how well.

I reckon we should look at this very carefully and ensure the structure is scalable but I believe make it easier for many new enthusiasts to get up to date info (or at least bit more up to date than Bob Brant's book, especially around battery technology) on what people are trying, also the concepts of what is required to build an electric car.


Solutions Knowledge Base

Posted: Sun, 30 May 2010, 22:15
by Richo
T2 wrote: johny you wrote -
      If my car cannot do Tollway/Freeway speeds then it's not really viable
Then what you are doing is really high end, IMO. Please accept the fact that few people have both the mechanicaI and electrical knowledge to reach that level. It's great that you're able to do it today at high efficiency but it comes with a price.

All the AEVA members in Perth cars can reach tollway/freeway speeds.
And that is one advantage of the AEVA - support from local people who CAN do it.
T2 wrote: In effect we want a Solutions Knowledge Base that will promote good outcomes, and I think that Squiggs & Co. agree with me. Yes there IS a useful search feature here but we need better organising to make it work better Hey, I didn't start this topic !!

Yep I think we all agree that we need somthing but it is a case of someone with the IT skill and free time to achieve it.
The forum software is not written by us so we can only do what the software allows us to do.
T2 wrote: I would like to see an AEVA agenda towards high rpm AC drives.
This is where I will disagree here.
Standard AC industrial motors with standard RPM limits of 4500-6000 is more than enough for 99% of eV's.
The only advantage of higher RPM is a smaller/lighter motor.
But for the sake of about 40kg weight saving I doubt it's worth it in a road car.
A standard AC induction motor running at 3500RPM through the diff reduction typically is around 100kph/60mph.
4500RPM would limit it to 130kph and 6000RPM to 170kph.
Using a 12000RPM tesla style motor is ~40kg lighter but some weight is taken up by the additional reduction to get it back down to a usebale RPM.

T2 wrote: Rewinding as tuarn (ACMOTOR) has done but at even lower voltages to permit packs with fewer but larger cells. Note that Toyota is staying with 201v for their PHEV design.
Winding a motor does have it's drawbacks.
And winding it to lower voltages will also increase your losses.
No comment on what Toyota is doing...
T2 wrote: Threads for new stuff
The Upconverter - idea borrowed from Toyota's Prius - . If you only need HV to be above 100v's while accelerating an upconverter looks to be a good idea, amazingly simple topology using only three significant components. It should be possible to take a Curtis or any other old DC drive which usually contain these parts and modify to suit.
The upconverter has been discussed.
You need the HV when you are above a certain speed regardless of acceleration.
It is simple in theory but trying to actually convert 50-100kW at 100V to 200V+ is both expensive and complicated to get working.
I believe the outcome of the thread was to get more batteries.
T2 wrote: This is a mechanical component not yet available in the EV market. It's an idea I had five years before the IMPACT in 1990 and others probably came up with it even years before that. I mentioned it somewhere here already should be a topic - needs attention of a mill wright:
Planetary gear reducer for mounting on the end frame of the motor
The motor end face would be one wall of the gearbox. The sun gear weould mount directly on the motor shaft. The hollow central part of the gearbox shaped to fit the endface could also mount the internal gear insert. Output shaft/ planetary carrier details TBD.
This "the motor is also the gearbox idea" would have two applications : -
Either Smaller high rpm motor to direct drive a diff
Or      with a larger ratio to direct drive the wheel.   
Yep not really comercially available for eV's.
And only really required if you have Tesla's motor where size matters.
But I guess if you have the money to spend on purchaing Tesla's motor you probably affort to have a cusotm planetary gearbox made anyway.
Application would be suitable for sports or race cars.
Otherwise an insdustrial AC induction motor can already connect direct to a diff without a planetary arangement.

Solutions Knowledge Base

Posted: Tue, 01 Jun 2010, 15:46
by T2
It is simple in theory but trying to actually convert 50-100kW at 100V to 200V+ is both expensive and complicated to get working

Should be easier than buck regulator. Since inductor could be "empty" when you come back on. I'll post later on DC upconverter thread in the coming weeks.

Yep I think we all agree that we need somthing but it is a case of someone with the IT skill and free time to achieve it.

Final words.

Solutions Knowledge Base

Posted: Wed, 02 Jun 2010, 02:32
by EVNoob
Well IT Skill is not hard, it is a matter of money actually.

Solutions Knowledge Base

Posted: Wed, 02 Jun 2010, 05:07
by Richo
AEVA is a non-profit association so doesn't have deep pockets to employ/contract someone with IT skills to create it.
It's more a case of a member with those skills to volunteer thier time.

Solutions Knowledge Base

Posted: Thu, 03 Jun 2010, 02:12
by EVNoob
I meant for the hosting etc

Solutions Knowledge Base

Posted: Thu, 08 Jul 2010, 04:21
by aegidius
.

Solutions Knowledge Base

Posted: Thu, 08 Jul 2010, 04:22
by aegidius
I really like the idea of a collection of data that car workshop manuals will not tell you. Things like:
- how much particular cars weigh, both tare and GVM
- how much the bits you take out weigh
- how much room there is for motor
- other gotchas, like how to deal with car computers when the engine is gone, and things that that which differ between models.

Wiki sounds good, since it's easily editable by all and sundry.