Nissan Leaf - Charging.

Nissan EV Interest Group
User avatar
acmotor
Senior Member
Posts: 3614
Joined: Thu, 26 Apr 2007, 03:30
Real Name: Tuarn
Location: Perth,Australia

Nissan Leaf - Charging.

Post by acmotor »

Good question.

Part of the answer may be that the EV battery pack is isolated and monitored from the EV earth.
Feeding it with a non isolated (from AC mains) DC power source would result in an earth fault error and the EV disconnect the charging itself. i.e. a bad boy charger ( directly rectified mains) would not work and without that earth fault monitoring, the EV body could become live or blow a big fuse somewhere.

TJ, your CHAdeMO would have DC earth fault monitoring in itself, in addition to the EV's monitoring ?
converted RedSuzi, the first industrial AC induction motor conversion
on to iMiEV MY12 did 114,463km
now Tesla Model 3, 4/2021 MIC pearl white
User avatar
coulomb
Site Admin
Posts: 6357
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Nissan Leaf - Charging.

Post by coulomb »

PlanB wrote: Why the mandated isolation xformer? An earthed 3 phase motor doesn't need one, nor does the VFD.

I think it's because an EV has capacitive coupling to the (usually) metal chassis. A non-isolated HF switch mode power supply would have high frequency square waves between windings and chassis. You could conduct a lot of that away through the earth lead, but they prefer no current at all through the earth lead (except briefly in a fault condition to clear a breaker or RCD). Inductance in the earth lead would mean that there would still be some bite to the metal in many circumstances.

[ Edit: this was not my best thought-through post. It's basically shot down in the next 4 posts. ]


DC motors with their brush dust would be an extra problem.
Last edited by coulomb on Mon, 30 Dec 2013, 03:27, edited 1 time in total.
MG ZS EV 2021 April 2021. Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
Patching PIP-4048/5048 inverter-chargers.
If you appreciate my work, you can buy me a coffee.
User avatar
weber
Site Admin
Posts: 2936
Joined: Fri, 23 Jan 2009, 17:27
Real Name: Dave Keenan
Location: Brisbane
Contact:

Nissan Leaf - Charging.

Post by weber »

coulomb wrote:I think it's because an EV has capacitive coupling to the (usually) metal chassis. A non-isolated HF switch mode power supply would have high frequency square waves between windings and chassis. You could conduct a lot of that away through the earth lead, but they prefer no current at all through the earth lead (except briefly in a fault condition to clear a breaker or RCD). Inductance in the earth lead would mean that there would still be some bite to the metal in many circumstances.

DC motors with their brush dust would be an extra problem.
But surely the only significant capacitance or conductance between battery and chassis is in the motor. And surely the motor must be isolated from the battery during DC charging.
One of the fathers of MeXy the electric MX-5, along with Coulomb and Newton (Jeff Owen).
User avatar
acmotor
Senior Member
Posts: 3614
Joined: Thu, 26 Apr 2007, 03:30
Real Name: Tuarn
Location: Perth,Australia

Nissan Leaf - Charging.

Post by acmotor »

weber wrote:
coulomb wrote:I think it's because an EV has capacitive coupling to the (usually) metal chassis. A non-isolated HF switch mode power supply would have high frequency square waves between windings and chassis. You could conduct a lot of that away through the earth lead, but they prefer no current at all through the earth lead (except briefly in a fault condition to clear a breaker or RCD). Inductance in the earth lead would mean that there would still be some bite to the metal in many circumstances.

DC motors with their brush dust would be an extra problem.
But surely the only significant capacitance or conductance between battery and chassis is in the motor. And surely the motor must be isolated from the battery during DC charging.


Yes to motor isolation during DC charging, as per the iMiEV circuit at least. Wasn't there a charging system by tesla that used the motor as inductor ?

Either way, a non isolated HF SMPS would be a buck converter whose output, if being fed to a battery at least, would have had ripple deliberately removed. i.e. no switching artifacts (easy HF filtering).
converted RedSuzi, the first industrial AC induction motor conversion
on to iMiEV MY12 did 114,463km
now Tesla Model 3, 4/2021 MIC pearl white
User avatar
weber
Site Admin
Posts: 2936
Joined: Fri, 23 Jan 2009, 17:27
Real Name: Dave Keenan
Location: Brisbane
Contact:

Nissan Leaf - Charging.

Post by weber »

acmotor wrote:Wasn't there a charging system by tesla that used the motor as inductor ?
Right. But that's for AC input. We're talking Chademo. That's why I wrote "isolated ... during DC charging".
Either way, ... would have had ripple deliberately removed. i.e. no switching artifacts (easy HF filtering).

Right. But I guess I'm in favour of hazardous EV voltages floating anyway. Is a HF transformer such a big deal?
One of the fathers of MeXy the electric MX-5, along with Coulomb and Newton (Jeff Owen).
Tritium_James
Senior Member
Posts: 683
Joined: Wed, 04 Mar 2009, 17:15
Real Name: James Kennedy
Contact:

Nissan Leaf - Charging.

Post by Tritium_James »

The main reason for the transformer is probably that they're being paranoid. It's probably not necessary, and it definitely adds a lot of cost, bulk, and losses.

Yes, our charger (and any Chademo charger) monitors both the AC side for earth leakage, and runs an isolation monitor on the DC side as well. This has to be capable of being self-checking. There's also a check that applies full voltage to the cable before the car closes it's battery contactors, to check for cable isolation faults, shorts, etc.

The charger has to also match the requested current/voltage from the vehicle quite closely, or the sequence gets shut down. There's quite tight timing requirements on comms, ramp rates, response times, etc. It's fairly complex.

We passed Chademo certification (in Japan) in the fastest ever time, apparently. Still took over a week...

Don't get me started on the SAE Combo standard - the comms for that are a nightmare!
User avatar
acmotor
Senior Member
Posts: 3614
Joined: Thu, 26 Apr 2007, 03:30
Real Name: Tuarn
Location: Perth,Australia

Nissan Leaf - Charging.

Post by acmotor »

Lets be honest. In the scheme of things, CHAdeMO isn't complex, just good practice. Image

Well done on the lightning approval. Image After all, it isn't that complex. Image
converted RedSuzi, the first industrial AC induction motor conversion
on to iMiEV MY12 did 114,463km
now Tesla Model 3, 4/2021 MIC pearl white
User avatar
acmotor
Senior Member
Posts: 3614
Joined: Thu, 26 Apr 2007, 03:30
Real Name: Tuarn
Location: Perth,Australia

Nissan Leaf - Charging.

Post by acmotor »

weber wrote:
acmotor wrote:Wasn't there a charging system by tesla that used the motor as inductor ?
Right. But that's for AC input. We're talking Chademo. That's why I wrote "isolated ... during DC charging".....


Well there you go, and I thought it was common practice to charge a battery off 'DC' anyway. Image Sorry, I do get what you mean, CHAdeMO and all that. I was just going one step further since the emotor is isolated during AC charging as well (except the case cited) since it is still DC charging, just with the AC to DC conversion onboard. Image Ho Hum.
converted RedSuzi, the first industrial AC induction motor conversion
on to iMiEV MY12 did 114,463km
now Tesla Model 3, 4/2021 MIC pearl white
User avatar
PlanB
Senior Member
Posts: 471
Joined: Sat, 16 Jan 2010, 15:24
Real Name: Kris McLean
Location: Freemans reach
Contact:

Nissan Leaf - Charging.

Post by PlanB »

Bit of thread drift here TJ & MX twins, but how onerous & expensive is the Leaf servicing regime? I'm almost tempted to raid the Model S sinking fund to buy one except that the thought of new car ownership & having to take it back to the dealership for servicing to keep the warranty alive chills me to the core.
PS: I'm liking the impressive dimensions of your CHAdeMO beast TJ. With the ever increasing trend to miniaturisation it's been a long time since I've seen a piece of electronics that comes in at 2 metres tall. Reminds me of some 19" rackmount from my youth!
User avatar
weber
Site Admin
Posts: 2936
Joined: Fri, 23 Jan 2009, 17:27
Real Name: Dave Keenan
Location: Brisbane
Contact:

Nissan Leaf - Charging.

Post by weber »

PlanB wrote: Bit of thread drift here TJ & MX twins, but how onerous & expensive is the Leaf servicing regime?
Just had first service. I have no idea what they did, except wash it, yay! But the first service is free. The next service is at 10,000 km and costs $90.
One of the fathers of MeXy the electric MX-5, along with Coulomb and Newton (Jeff Owen).
Tritium_James
Senior Member
Posts: 683
Joined: Wed, 04 Mar 2009, 17:15
Real Name: James Kennedy
Contact:

Nissan Leaf - Charging.

Post by Tritium_James »

Yep, we paid $80+GST for the last service on ours. I think they check the wheels are still attached and give you the battery health printout!
User avatar
PlanB
Senior Member
Posts: 471
Joined: Sat, 16 Jan 2010, 15:24
Real Name: Kris McLean
Location: Freemans reach
Contact:

Nissan Leaf - Charging.

Post by PlanB »

OK I'm confused now. Went to a Nissan dealership & they have an Origin energy charging station about the size of a scuba tank plugged into what looked like a 3 phase outlet. They reckoned it recharges their demonstrator in 2 hours. That's too quick to be J1772 so it's got to be CHAdeMO right? I thought fast DC chargers were all 6' tall like TJs VeeFill? The Leaf is areal nice experience by the way, I'm very tempted.
User avatar
Simon
Senior Member
Posts: 433
Joined: Sun, 19 Aug 2007, 19:38
Real Name: Simon
Location: Perth WA
Contact:

Nissan Leaf - Charging.

Post by Simon »

Would be a j1772 EVSE and clueless salesmen. Although if it was a 6.6kw leaf then 2hours would be all it would take to recharge from 50%..


User avatar
PlanB
Senior Member
Posts: 471
Joined: Sat, 16 Jan 2010, 15:24
Real Name: Kris McLean
Location: Freemans reach
Contact:

Nissan Leaf - Charging.

Post by PlanB »

I think you're right Simon. The module looks like a free standing level2 (7kw)from the Origin website to me. Thing is the car I drove is a 2013 demonstrator so it's limited to 3.3kw anyway. I had lots of questions about the Leaf's GPRS based telematics etc, but soon learned the sales person is not the one to ask.
whimpurinter
Senior Member
Posts: 513
Joined: Tue, 05 Jul 2011, 16:32
Location: Brisbane

Nissan Leaf - Charging.

Post by whimpurinter »

When I have looked at a new Prius on a couple of occasions separated by a year or so, I found that that there seemed to be maybe just one salesman out of all of them who was THE MAN to talk to.   What that man really knew no longer worries me though they seemed ok.   The salesman we bought one off was very pleasant (and I must get on to the sales report thingie and tell Toyota so) and didn't profess to know a lot about it. It didn't matter as I was quite happy to find out for myself. I suppose the thing is that they are salesmen, not information providers, whatever we would like them to be.
I've seen somewhere that a salesman is really only a salesman if the customer bought a car only after at some point, having decided that they were definitely not going to buy a/the car.
User avatar
Johny
Senior Member
Posts: 3749
Joined: Mon, 23 Jun 2008, 16:26
Real Name: John Wright
Location: Melbourne
Contact:

Nissan Leaf - Charging.

Post by Johny »

PlanB wrote:That's too quick to be J1772 so it's got to be CHAdeMO right? I thought fast DC chargers were all 6' tall like TJs VeeFill? The Leaf is areal nice experience by the way, I'm very tempted.
They take it out for a test drive then plug it in and it takes two hours to charge. That's a two hour charge - right.
Tritium_James
Senior Member
Posts: 683
Joined: Wed, 04 Mar 2009, 17:15
Real Name: James Kennedy
Contact:

Nissan Leaf - Charging.

Post by Tritium_James »

Yep, it's limited by the 3.3kW charger in the car, so it's still 6-8 hours for a full charge. The salesmen are completely clueless about DC fast charging - the guy that sold ours didn't even know what the 2nd charging connector in the car was for...

PlanB, don't put too much hope on the telemetry. It's flaky and mostly useless. Most trips on our Leaf don't even show up on the website, and the ones that do are quite obviously the wrong distance. In fact I think you'd have to try pretty hard to make it any worse!
User avatar
E-STATION
Groupie
Posts: 145
Joined: Wed, 28 Jul 2010, 18:05
Real Name: Patrick Finnegan
Location: Perth
Contact:

Nissan Leaf - Charging.

Post by E-STATION »

PlanB wrote: OK I'm confused now. Went to a Nissan dealership & they have an Origin energy charging station about the size of a scuba tank plugged into what looked like a 3 phase outlet. They reckoned it recharges their demonstrator in 2 hours. That's too quick to be J1772 so it's got to be CHAdeMO right? I thought fast DC chargers were all 6' tall like TJs VeeFill? The Leaf is areal nice experience by the way, I'm very tempted.


The charging stations provided by the Nissan dealers are J1772 and deliver up to 32 amps. AFAIK there are no CHAdeMO charging stations installed in any Nissan dealership.
User avatar
PlanB
Senior Member
Posts: 471
Joined: Sat, 16 Jan 2010, 15:24
Real Name: Kris McLean
Location: Freemans reach
Contact:

Nissan Leaf - Charging.

Post by PlanB »

Good grief! Had a Leaf on charge here overnight, who's idea was it to insert a house brick in the cable 6" from the plug? Apart from a few blinkin' lights & the J1772 oscillator what other stuff could possibly be in there to make it so heavy? Recharged 100km in 5 hrs = 5 x 10 x 240 = 12kwh? So that makes the Leaf a 120wh/km drive?
User avatar
Johny
Senior Member
Posts: 3749
Joined: Mon, 23 Jun 2008, 16:26
Real Name: John Wright
Location: Melbourne
Contact:

Nissan Leaf - Charging.

Post by Johny »

Ha. I agree with the brick comment. The best power economy we ever got was closer to 170Wh/km and that was on the car display - not the charging. As said earlier - it was during winter - but the days I drove it I turned Climate control off and it still wasn't anywhere near the iMiev (or Vogue).
User avatar
g4qber
Senior Member
Posts: 2022
Joined: Sat, 31 Jul 2010, 06:27
Real Name: Joseph
Location: Perth
Contact:

Nissan Leaf - Charging.

Post by g4qber »

Brian M's leaf drew 18A from e-station's 16A fbox
this box had a component replaced though.

the 15A Clipsal Powermate powermeter was having its overload LED lit.

will have to re-check this one day.

the genuine "emergency" Nissan EVSE was drawing <10A; which was good to know for Brian.
Last edited by g4qber on Thu, 12 Sep 2013, 05:50, edited 1 time in total.
User avatar
PlanB
Senior Member
Posts: 471
Joined: Sat, 16 Jan 2010, 15:24
Real Name: Kris McLean
Location: Freemans reach
Contact:

Nissan Leaf - Charging.

Post by PlanB »

Yeah I'm a bit suspicious, 120Wh/km seems too good to be true but the EVSE kit that came with the car was definitely drawing only 10A and the range meter did go from 53km to 159km in 5 hrs
User avatar
leighf
Groupie
Posts: 44
Joined: Fri, 25 Apr 2008, 18:08
Real Name: Leigh Fiddes
Location: Melbourne

Nissan Leaf - Charging.

Post by leighf »

I've been routinely getting (according to the dash) 160Wh/km in winter and was getting 140-150Wh/km in summer so 120Wh/km sounds suspicious to me as well.

The guess-o-meter is however notoriously optimistic so the indicated 100km of range added is unlikely to be achievable.

Leigh
2012 Nissan LEAF, Cayenne Red
Purchased July 2012.
User avatar
PlanB
Senior Member
Posts: 471
Joined: Sat, 16 Jan 2010, 15:24
Real Name: Kris McLean
Location: Freemans reach
Contact:

Nissan Leaf - Charging.

Post by PlanB »

Interesting. I should have checked the mains current when we unplugged, maybe it tapered off throughout the 5hrs?
User avatar
PlanB
Senior Member
Posts: 471
Joined: Sat, 16 Jan 2010, 15:24
Real Name: Kris McLean
Location: Freemans reach
Contact:

Nissan Leaf - Charging.

Post by PlanB »

Better price than Origin energy, not sure the curled up cord is a good idea.
Post Reply