Simple fast charging

[arsharpe]

From original post

I wonder how difficult it would be to tap into the main motor cables and make the van think it is regen current it is getting. So hook up extra batt set greater than normal pack voltage, disconnect one motor cable and then switch on ignition and the controller will think it is regen current appearing on the motor....

Initially when I first saw this I thought it was a bit basic and may have had problems. Sorry "Flying John" as with all things elegant it has taken some time for me to catch-up with your advanced thinking.

This thread was extracted to discuss this further.

Just to clarify the advantages of "Flying John's" idea.

- the main motor cables are easily accessible from the controller top cover
- unlike the normal fast charging method that requires a separate charge monitor circuit to inform the Berlingo the amount of charge being accepted, this uses the inbuilt battery monitoring circuit.
- it would probably be a lightweight solution (using the existing circuits)
- the developer can choose the exact fast charge duration and can vary for individual situations (simply by changing the number or sizez of switched mode power supplies used).

Just to clarify that I think that this approach would probably only be suitable for fast charging down to 1 hour or longer (so that the max current is no different than normal discharge current).

I am very interested in people's thoughts as it is something that I would like to try.

[ChrisB]

That acutally isnt such a bad idea, although while carrying out this charge you would need the van to be up and running i.e in go mode, also I wonder how the feild windings would feel or would you disconnect them during this, but then would the controller realise this and lock down ??

I think the first thing would be to dissconnect the motor connections and see if the controller will "power up" from there put it in fwd mode and see if its still happy, after that then feed in a DC voltage back up the main motor connections and see what happens, I'd personally start with something like a crude variac and DC circuit so you can monitor whats going on, I wonder though what the chopper circuits would make of it or if at rest they switch out.
Of course knowing the berlingo the dam controller will realise things aint going round via possibley a VSS and thus lock down

Interesting concept and good bit of side ways thinking, must have missed Johns orginal post

ChrisB

[arsharpe]

Good plan Chris I will try that shortly.

[EVan]

Sorry to shoot this down but I really don't see the point (and frankly it sounds like a good recipe for blowing something up).

Connect your external charger to the external charge terminals and... It'll just work... See my fast charger below.

[Flying John]

Another solution is to have a a small one wheel rolling road arrangement (like an MOT brake tester) in the floor of your garage. You drive onto it and the wheel revolves driven by an electric mains motor and its like you are going down a hill with maybe 100 amps of regen current, giving you a fast charge.

Downside is the brushes are getting "double usage" and the speedo and oddometer are going to go round as if you are moving.

If the regen current were say 100 amps then this is 15+KwH per hour - so if you could do this for say 30 mins it would give you a healthy quick charge up.

John

[EVan]

Another solution is to have a a small one wheel rolling road arrangement (like an MOT brake tester) in the floor of your garage.

Again, sorry to be negative but this is a somewhat heath-robinson approach, and likely to be vastly more expensive and troublesome than simply using a battery charger!

[arsharpe]

Evan, thanks a lot for your reply.
Where is the "fast charger below" ?

[EVan]

http://www.tuer.co.uk/my-evs.htm - second picture down (sorry there's not much info).

[arsharpe]

Hi Evan,

Thanks for the link and the charger looks great.

(In soft tone voice )

When I asked before you were unwilling to release design information, which is understandable, but unfortunately, you would not sell the units either.
So where do we go from here ?

I am sure that there are other people that would love to charge in sub 3 hr rates.

As no one else is doing anything similar for the PSA vehicles, it really doesn't leave people much choice.

I believe I am correct in saying that assuming that we could get the very expensive high power charging lead, using a "normal" NiCd charger will confuse the controller as it does not know the batteries have been charged.

Either way without a 'proper' charger like yours it always going to be a botch.

Any help you can provide us would be great.

[EVan]

When I asked before you were unwilling to release design information, which is understandable, but unfortunately, you would not sell the units either.

Well, to be more accurate my one wouldn't be legal to sell.

I could sell one made with off the shelf parts but any time I have offered this it's been considered too expensive, so I've stopped offering

And I've advised plenty of people how to go about building one yourself (for example with surplus parts, as the one in the picture is), I can't remember the conversation we had though, so apologies if I'm contradicting myself, we all learn.

I believe I am correct in saying that assuming that we could get the very expensive high power charging lead, using a "normal" NiCd charger will confuse the controller as it does not know the batteries have been charged.

No, the controller will know they have been charged.


Simple recipe:

Buy or make a current source (say, 50A). Rig it to turn off at 200V. Connect it to the external charge terminals.
Keep an eye on it when it's charging, using evlite.

Job done!