IT angle
This may displace the claims of the Power over Ethernet people that their socket is the only 'power outlet' which is the same in every country on earth.
US, Euro e-car makers back 'standard' AC/DC jack
Audi, BMW, Daimler, Porsche and Volkswagen have joined Ford, Chrysler and General Motors to back a standard fast-charge connector and jack for e-cars. The system combines a multi-pin AC port with a two-pin DC inlet. Slow, but cheap, overnight charging is handled by the AC lines, but drivers will be able to use the same …
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Friday 4th May 2012 10:55 GMT Blofeld's Cat
@Extra pins
Split phase, signalling and vehicle detection.
There's some pretty hefty voltages (600 VDC) and currents (400 A) involved as well.
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Friday 4th May 2012 10:46 GMT Lee Dowling
That has to be the ugliest socket I''ve ever seen in my life. Even SCART and DVI were more elegant.
What was wrong with just putting a pair of DC pins side by side in a large-enough connector, and maybe one small one for some kinda "sense/data" pin that could also act to key the connector's polarity? AC pins are going to differ in voltage and frequency anyway and you're going to have them handle them in the car by, well, converting them to DC. Surely that's better done at the fuelling station AND home charger than anywhere else, otherwise they would just add weight to the car and be skimped upon (and be upgrade-proof!)?
Or is this is a drive to "sell" you 100 KWh of AC electricity that is only 90KWh once you have DC losses and only 80KWh once your battery gives you it back? Push the thermal / conversion losses onto the poor sap stupid enough to buy an electric car?
Still have yet to actually see anyone in real life top up an electric car, though, and I live inside the M25 and do an awful lot of driving.
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Friday 4th May 2012 11:14 GMT Lee Dowling
Re: Connector design
And how does that help make the connector more complex (and the same connector is used for "home" fill-ups too - that's one of the stated points of the standardised, dual-power adaptor!)?
That amount of power, in a female socket means you have to jab metal objects into the end to short it. It will be suitably fused, but more importantly it will probably have contact-sensing (like any modern "jumpstart" battery - if you short the connectors at any point, no power flows - power is ONLY applied when it's probed the other end and found a load that's suitable for charging and operates on dumb principles because lead-acid batteries don't have any circuitry!). Failing that, the "keyed" connector should ensure that there's contact and could even be designed to relay correct physical contact of the connector back to the "pump" which only switches on when it's been told that the connector is mated properly (can be as simple as a spring-button lock on the connector that only operates when "latched" into the correct socket).
If it hasn't, I refer to my original point - what a crap, overcomplicated connector.
And I'd rather have two huge meaty inch-thick DC cables that do auto-sensing than all that gumph which just looks ripe to go wrong in the case of a sheared cable or damaged connector (you're telling me that little old ladies trying to force that into their car's port sideways for years at a filling station won't eventually break those plastic interiors and make the AC contact the DC?).
It just seems an incredibly ugly, overcomplicated and poor design to make dual AC/DC connectors and pumps and then rely on convertors inside your car (and your problem if they blow up and you can't charge your car any more) rather than just pushing ONLY DC and doing all the messy, expensive conversion before you shove things down a standardised, minimalist connector that needs as little as possible done to it afterwards and metering it from actual, usable DC power at the point of filling.
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Friday 4th May 2012 12:29 GMT Ru
Re: "rather than just pushing ONLY DC"
If your car accepts standard AC, you can charge it anywhere regardless of the availability of charging equipment. You could just nail a suitable plug onto the end of a standard domestic power lead or industrial 3phase outlet... this is pretty much how basic home charging is done on most e-vehicles anyway.
Making the charger optional makes life easier for everyone, except the sorts of people who get angry about power sockets.
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Friday 4th May 2012 11:42 GMT Blofeld's Cat
Re: Connector design
It wouldn't be beyond the wit of man to automatically stop the e-car from driving off if the charger's attached!
Quite so. Unfortunately people tend to underestimate the capabilities of idiots.
Motorhomes have interlocks to prevent the engine being started if they are plugged into a hook-up bollard, and yet I repair or replace several hook-up bollards every year.
It just takes a small piece of grit, a loose connection or the supply being turned off and twang!
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Saturday 5th May 2012 18:28 GMT Alan Firminger
Guesswork
Look at the pictures. And remember that cars travel around.
The plug mains connector shows what we can assume is two pins and earth. There is also space for different configurations around the earth.
The socket shows five pins for mains and a blank space. One pin has to be neutral.
The plug will give connection to one of four voltage options.
Your car has an input voltage appropriate to the market, which means you have a connector that selects what it wants. Public recharge stations, perhaps in hotels and car parks, offer all the voltages.
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Friday 4th May 2012 11:14 GMT Charles 9
Re: Anti tamper?
IIRC the AC part of the plug's designed to be used in an enclosed setting, such as a garage. If the chav can get into the garage to reach your plug, you have bigger problems than them making off with the cable.
As for the DC part, this is meant for quick applications so exposure there would be limited: more like at the filling station.
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Friday 4th May 2012 11:30 GMT Omgwtfbbqtime
Re: Anti tamper? @Charles9
The charging stations I have seen so far (in LocGov owned/operated car parks) do not have their own cables attached as far as I could see.
I have never seen any of these bays occupied - though the maximum stay 4 hours sign Sunderland Council have inflicted on these bays may have more to do with that.
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Friday 4th May 2012 15:23 GMT Phil O'Sophical
Re: Anti tamper? @Charles9
>: do not have their own cables attached as far as I could see.
That's because such cables are likely to suffer the same fate as garage airlines. Give the charging point a socket, and have the cable attached to the car. That way you have some change of finding a usable charging point.
Or just use a liquid like biodiesel or ethanol. Tried & tested.
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Saturday 5th May 2012 12:53 GMT Charles 9
Re: Anti tamper? @Charles9
"Or just use a liquid like biodiesel or ethanol. Tried & tested."
And then rejected. Diesel is too polluting, and biodiesel too low in volume to use mainstream. Meanwhile, ethanol isn't as powerful as petrol and can't be produced in mainstream volumes without eating into food supplies. Meanwhile, synthetic petrol production is still in the initial phases. I would be great if it worked out, thought we'd still need a source of vast power to produce it all (*yawn* call me when you can present a cost-effective land-effective non-fossil non-nuclear power plant design in the 2GW range or so--then we'll talk).
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Friday 4th May 2012 12:01 GMT Steve Button
Re: Anti tamper?
Charles 9, errrr No. these things are popping up outside of many buildings (like the office I'm sitting in which has a couple, although I've never seen them used). It's a really good point about anti tamper. It just needs a place where you can attach a padlock or something similar, but you just know someone is going to be left sitting on the tarmac because a) someone has decided to maliciously unplug them or b) someone else with an electric car hijacks your juice.
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Friday 4th May 2012 11:19 GMT Lee Dowling
Re: Anti tamper?
They'd be too busy sticking two pounds into a charging station and then finding ingenious way to blow it up like connecting it to a nearby lamppost, arcing them to each other, sticking their finger in it or whatever else.
Electric cars are a really stupid idea at the moment anyway. Charge time in hours is the cause of the problem you describe and one of their biggest downfalls. A tank-filling time in minutes means most people don't leave the car unattended while fuelling. A similar charge time would do the same but because of the sheer huge nature of the power involved (the equivalent of a tank full of petrol, which is extremely safe considering its energy density), it's not going to happen for a very, very, very long time and even then still be more dangerous.
Hopefully, we'll stop all this electric junk soon and come up with something that's likely to actually work better than a milk float (all-electric since the 1960's, I believe).
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Friday 4th May 2012 13:39 GMT Anonymous Coward
lmgtfy @easyk
No, not two 120V lines. Residential distribution is single phase 240V. There are transformers on the poles with a center tap. Every house has three wires: two hot and one neutral/ground connected to the center tap on the transformer and to ground in the house. Use the two hot wires, you get 240V; use one hot and the neutral you get split-phase 120V. The electric panel divides half the 120V circuits on one hot lead, and the other half on the other lead.
Electric water heaters, stoves/ovens, heating systems, clothes dryers, and the rare heavy duty appliance all run on 240V; everything else runs on 120V.
Is that the same as two 120V lines that are 180° out of phase? Seems like it could be hard to keep two independent 120V feeds in phase; easier (if more expensive) to use a transformer to split a single phase 240V supply.
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Saturday 5th May 2012 18:45 GMT Alan Firminger
230 volt supply was agreed as a European standard giving an acceptable compromise between the continental 220 volt standard and the UK's 240 volt. This was settled about 1988, I am not going to research that - just accept a long time ago.
Prior to this and after we all had and have a supply spec within plus and minus 6 % . The continentals had many supplies below tolerance, so they made an effort and solved two problems, probably helped by a grant from Brussels.
There are still 220 volt goods on the continent and many of us have legacy 240 v items. No matter.
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Friday 4th May 2012 13:32 GMT Chris Miller
Back of the envelope
With a 100kW connector, you can charge your 30kWh battery in only 20 minutes (just time to get a cup of coffee). But how much heat does that generate? Do these vehicles allow for the dissipation of 10kW of heat (assuming the charging process is 90% efficient, which is probably wildly optimistic)?
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Monday 7th May 2012 18:39 GMT Orv
Re: Back of the envelope
Most electric cars have a small radiator to dissipate heat from the electronics and in some cases the battery pack. I know on the Tesla the radiator fans will cycle on as needed during charging to keep the electronics cool; I'm sure other electric cars are similar.
10 kW is about the equivalent of the waste heat from a 20 shaft horsepower engine. It doesn't take much to dissipate that. It's easy to lose sight of just how massive the heat dissipation from a traditional car needs to be.
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Friday 4th May 2012 13:41 GMT Anonymous Coward
What about insertion force?
I have had occasion to use the 32 and 63 amp standard 3 phase 415 volt plugs and sockets. A lot of force is required to mate and seperate them. Are figures for mating/seperating force for these new plugs availaible? How does it compare to the typical strength of an 75 year old female?
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Friday 4th May 2012 21:20 GMT JustNiz
DC pins
I hope that the cable is actually the supply side and the socket block is whats fitted to the car.
If not there's a big problem.
Given they can be carrying up to 500V at 200A, and that DC tends to weld you to the connector, .the DC pins at the bottom of the socket especially, look way too easily touchable especially for small children's fingers.
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Saturday 5th May 2012 08:21 GMT Richard 12
Ceeform?
What exactly was wrong with CEEFORM?
Was it simply that it's already a standard for all the voltages and currents used, colour-coded, tested and has pilot pins available to ensure a good connection is made before applying power and to unpower during disconnection?
I see no pilot pins on the plug shown, so this thing is really going to arc.
It looks like it has all the disadvantages of CEEform and none of the advantages.
No covers over the pins on either side, so kids can stick spoons in them.
Send the designers home, they have no clue.
Bring back the people who designed the UK plug.
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Saturday 5th May 2012 11:38 GMT John Smith 19
*Something* like this had to happen
It's a sign of moving out of the "Early adopter" phase into a more mature stage
It's the difference between private mobile radio networks (the sort run by cab companies) and cellular networks with roaming.
The joker in the pack is the chicken and egg timing between the infrastructure suppliers (who'll want to get the switchover started) and the EV mfgs, who'll want to leverage their existing (and incompatible) designs as long as possible.
Hopefully this decision will let new infrastructure developers start rolling out a *common* connector at last.
As usual with technology standards the question will be how fast will technology develop to the point this will have to be updated (are any of those pins "not connected" for later usage?).
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Saturday 5th May 2012 18:38 GMT Walter Bays
Standards - so many to choose from
The plug isn't energized until a handshake protocol with the car assures that the plug is correctly inserted. So no danger in licking the plug, though I wouldn't do it as it would be unsanitary and foul tasting.
Cars start charging at 50 kW and quickly ramp down. You get most of your charge in the first 10 minutes, and probably wouldn't wait much past 30 minutes. So using these DC quick charge stations you'd probably wait with the car or have a coffee nearby. For slower AC charging you'd likely be away from the car at a restaurant, movie, or shopping. And of course you no more need the AC and DC electrical plugs combined than you need your diesel and gasoline nozzles combined at the gas station.
The car won't start while plugged in, so you can't drive away with the cord. Quick charging is more suitable for modest road trips than serious cross country trips, though these guys drove 1,254 km in 24 hours: http://www.youtube.com/watch?v=R9NqSuk5gjQ
Why wouldn't they adopt and extend the existing CHAdeMO quick charging standard that has thousands of chargers and vehicles already in place? The main purpose of the SAE appears to be to stall the EV market for a few years with the confusion of multiple standards, so that the sponsoring American and European car makers can catch up to the Japanese car makers.
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Saturday 5th May 2012 18:39 GMT martinwinlow
Er, ... so where does Mennekes (IEC 62196-2) fit in to all this? This socket is already the most widely adopted, non-Chademo type 2 socket in Europe and also championed by Daimler. Is this going to be abandoned in favour of the 'J1772 Combo'?
Looking at the pins on the Combo, it looks like the top half is Mennekes (2 or 3 phase AC power and 2 signal) and the bottom half Chademo-like DC. Maybe its a sensible bringing together of both. I'm confused whey they call it the J1772 Combo' as J1772 appears to have been left out altogether. As someone else said, I don't much care what standard is adopted - let's just get on with it! MW
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Monday 7th May 2012 16:25 GMT Alan Brown
I was hoping
For a unified CABIN standard dammit.
Back to the matter at hand. From the wikipedia article:
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Connector
The connector is designed for single phase electrical systems with 120 V or 240 V such as those used in North America and Japan.
The round 43 mm diameter connector has five pins, with 3 different pin sizes
AC Line 1 and AC Line 2 - have same size power pins
Ground Pin
Proximity Detection and Control Pilot - have same size pin
Proximity Detection - Prevents movement of the car while connected to the charger.
Control Pilot - Communication line used to coordinate charging level between the car and the charger as well as other information.
The connector uses a 1 kHz square wave at +/- 12 volts generated by the Electric Vehicle Supply Equipment (EVSE), i.e. the charging station, on the pilot pin to detect the presence of the vehicle, communicate the maximum allowable charging current, and control charging.[13] The connector is designed to withstand up to 10,000 connection/disconnection cycles and exposure to all kinds of elements. Approximating one connection/disconnection cycle daily, the average connector's lifespan should be just over 27 years.
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I'm amazed they think that one connect/disconnect cycle per day is enough to design for. Somehow I predict the average connector lifespan to be about 6 years in the real world on cars and something less than 18 months on public charge posts.
As for the "proximity sensor" - unless this works until the connector bodies are well clear of each other there are going to be driveaway incidents - and if it does work like that it's going to be fun to make some "dummy plugs" and stall cars simply by slapping 'em on the bodywork near the chargepoint.
Discussions about 120/240V are largely irrelevant unless the design allows for less than 2kV live/earth isolation. (Lightning strikes are a bitch). It's not as if universal switchmode supplies are a new invention - and for real charging oopmh you'll need 400/440V 3 phase - which is more or less the same in all countries apart from frequency. It'd be incredibly shortsighted not to design for that too.
High voltage/current DC on a consumer-demountable conector = massive fail. DC arcs aren't self-extinguishing.
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Monday 7th May 2012 18:43 GMT Orv
Re: I was hoping
While DC arcs aren't self-extinguishing, they will extinguish when the power is cut off. ;) I'm guessing an interlock will cut off the high voltage power the instant the handshake pin disconnects -- and if they follow good connector design guidelines, the DC pins will be longer and make first/break last. As a backup I would expect either a high-voltage DC breaker or a fast-acting silver-sand fuse.
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Tuesday 8th May 2012 07:44 GMT Charles 9
Re: I was hoping
"I'm amazed they think that one connect/disconnect cycle per day is enough to design for. Somehow I predict the average connector lifespan to be about 6 years in the real world on cars and something less than 18 months on public charge posts."
Remember, the intention is that the vehicle only gets plugged in at home when it's done for the day and then unplugged the following morning, so yeah once a day.
As for public connectors, it would simply need to be built to higher spec to withstand more abuse, probably with a quick-disconnect design to minimize damage in the event of a drive off (which one of the sense pins is supposed to prevent anyway). Petrol hoses get their knocks as well and have to be maintained or replaced every so often as well, so this isn't anything new.
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Biting the hand that feeds IT
