Yeah, I had that linked from my EV charging page for a while now...
And previously mentioned in this topic.
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Charging the Roadster - EU Style
- Thread starter EV_de
- Start date
Yeah, I had that linked from my EV charging page for a while now...
And previously mentioned in this topic.
Yes, from what I've seen the Mennekes connector looks very versatile and well thought out. I wish we could just adopt this standard globally.
TEG has a charging page! :wink:
By the way, this bit...
...isn't quite right - the colour just signifies the voltage. You can have three phase blue ones (indeed, this would be the type for the US 208V system). Also, IEC is as much American as European, even if their Boston office isn't very vocal on EV connectors!
Another minor niggle: 480VAC@400A 3P is 332kW, not 192kW (multiply by sqrt 3).
This page has a nice summary of the issues. Interestingly, they claim that the Mennekes connector is pin compatible with J1772-2009 in single phase mode. Looking at the pinouts, I can't see how that is the case - did I read that right?
What does appear to be the case from the above presentation and some of the links on TEG's site is that the pilot signal is the same on both the Mennekes (inherited from IEC 309-2) and J1772, so an adapter should be easy at least.
This IEC 62196-2-X document outlines the Mennekes connector, so it clearly is not some kind of industry-only standard.
It also appears that the baseline standard is for 32A, with "case C charging" extending that to 63A three phase and 70A single phase. I guess Menekkes adopted this case, as their press release claims they can handle this current. SAE 1772 is mentioned in the introduction, but not again in the main document.
By the way, this bit...
...isn't quite right - the colour just signifies the voltage. You can have three phase blue ones (indeed, this would be the type for the US 208V system). Also, IEC is as much American as European, even if their Boston office isn't very vocal on EV connectors!
Another minor niggle: 480VAC@400A 3P is 332kW, not 192kW (multiply by sqrt 3).
This page has a nice summary of the issues. Interestingly, they claim that the Mennekes connector is pin compatible with J1772-2009 in single phase mode. Looking at the pinouts, I can't see how that is the case - did I read that right?
What does appear to be the case from the above presentation and some of the links on TEG's site is that the pilot signal is the same on both the Mennekes (inherited from IEC 309-2) and J1772, so an adapter should be easy at least.
This IEC 62196-2-X document outlines the Mennekes connector, so it clearly is not some kind of industry-only standard.
It also appears that the baseline standard is for 32A, with "case C charging" extending that to 63A three phase and 70A single phase. I guess Menekkes adopted this case, as their press release claims they can handle this current. SAE 1772 is mentioned in the introduction, but not again in the main document.
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Excellent find. Thank you.
I particularly like the reversible portable cable idea on slide 21 and the summary on 39.
Only slight gripe with the recommendation of a screw cover on vehicle charging ports. Would prefer a lockable flip-lid.
I expect that is necessary to get the IP65 rating on the connector when not in use - necessary for car washes and the British weather this summer.
While this isn't a dedicated 3P > 1P converter, I've seen that Mitsubishi make very compact inverter-based motor controllers which perform a similar function (and more).
These devices are again using power electronics, rectifying the incoming 3P AC to DC, then reconstructing a variable frequency and voltage 3P waveform to run the attached motor efficiently. It seems to me that if the output stage was programmed to invert all three phases in phase (i.e. 0 deg offset) and the output was paralleled, this would virtually give us what we want. (of course, with a new design it could be a single inverter stage.)
Conceptually, it looks like this:
The 7.2kVA model measures 108x128x165mm and weighs 1.5kg. The 13kVA model is 220x150x147, 3.2kg. The 23kVA model is 220x260x190, 5.9kg. Losses range from 180-500W.
Manual
Better still, they are under £1000.
Am I totally barking up the wrong tree, or does this show that there is no fundamental reason why a lightweight, portable converter can't be built?
As an aside, even the 0.5MVA ones are ~£30k. I wonder if this is a good pointer for the eventual cost of a fast charger?
These devices are again using power electronics, rectifying the incoming 3P AC to DC, then reconstructing a variable frequency and voltage 3P waveform to run the attached motor efficiently. It seems to me that if the output stage was programmed to invert all three phases in phase (i.e. 0 deg offset) and the output was paralleled, this would virtually give us what we want. (of course, with a new design it could be a single inverter stage.)
Conceptually, it looks like this:
The 7.2kVA model measures 108x128x165mm and weighs 1.5kg. The 13kVA model is 220x150x147, 3.2kg. The 23kVA model is 220x260x190, 5.9kg. Losses range from 180-500W.
Manual
Better still, they are under £1000.
Am I totally barking up the wrong tree, or does this show that there is no fundamental reason why a lightweight, portable converter can't be built?
As an aside, even the 0.5MVA ones are ~£30k. I wonder if this is a good pointer for the eventual cost of a fast charger?
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If they've been able to shrink the size of the new PEM, this sort of circuit could be added within the existing frame of the vehicle. Also allowing the internal cable between the PEM and the charge socket to be made a bit lighter.
Roadster 3.0?
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Well, incorporating three-phase charging into the vehicle would be the best option for EU cars - but if we are going to get into that game then using the regen circuit would be more economic...
But there is a question if the regen circuit really could sustain continuous current for a whole charge cycle like that.
Would 3 phase line current be comparable to AC current coming from a 'regenning' drive motor?
Also how do you switch the connections from the motor over to the 3 phase charging circuit?
I suspect it is all doable, but there might be some complications.
The European standard charging plug for cars is selected after Mennekes design — Autoblog Green
The Mennekes charging standard is a bit puzzling.
"The plug works both for single phase 230-Volt connections, the vast majority of European outlets, as well as three-phasing up to 63 amps and 400 Volts, which results in a much shorter recharging time."
Tt doesn't sense that all European EVs would have the same connector even though not all European EVs would charge charge from three-phase/single-phase.
Diesel stations have different nozzles than gasoline stations, shouldn't it be the same for single-phase vs. three-phase charging?
Shouldn't the connectors be different to avoid the balancing issues you guys were talking about at the beginning of the thread?
The Mennekes charging standard is a bit puzzling.
"The plug works both for single phase 230-Volt connections, the vast majority of European outlets, as well as three-phasing up to 63 amps and 400 Volts, which results in a much shorter recharging time."
Tt doesn't sense that all European EVs would have the same connector even though not all European EVs would charge charge from three-phase/single-phase.
Diesel stations have different nozzles than gasoline stations, shouldn't it be the same for single-phase vs. three-phase charging?
Shouldn't the connectors be different to avoid the balancing issues you guys were talking about at the beginning of the thread?
I am fully convinced that, in specifying the requirements for this standard, RWE and it's partners have understood something profound: that the biggest remaining obstacles to practical use of EVs as primary cars are:
1. How to drive a long distance down the autobahn in a single day on the occasions when I need to.
2. How the millions of apartment-dwellers should recharge routinely.
RWE have addressed this by choosing to offer up to 400V 3-phase 63A for recharge. This delivers a 43 kW charge rate.When combined with around 50kWh batteries (in the model of Tesla) the impact is game-changing.
Consider a car with the range of the Tesla Roadster (200 miles Range Mode with the central 160 miles routinely used in Standard Mode). Those central 160 miles use 80% of 53 kWh ~= 43 kWh. So on a 43kW charger the Roadster could in principle recharge 43kWh in an hour (ignoring charging losses) or 160 miles range per hour.
Note: this combination doesn't exist yet because Tesla doesn't support 3-phase charging.
Nevertheless RWE are taking a bold step of the "if you build it they will come" variety. And in my view they have found a sweet spot that manages to exceed a new threshold of user acceptance and yet is within the capability of utilities to deliver cost-effectively.
What are the implications of 160 mph charging?
1. You can cruise down the autobahn/motorway/interstate for 2-2.5 hours, covering around 160 miles, then take a one hour break for comfort and recharge, then cover another 160 miles, another 1 hour charge and comfort break, and repeat ad infinitum. (or variants like drive 100 miles, charge 40 minutes, repeat)
To me this 2:1 drive:rest ratio seems entirely acceptable. I think a large fraction (but not all) of the population would agree (agreeing: those who roadtrip less often and when they do drive up to 500 miles per day requiring just two intermediate 1 hour breaks assuming charging at either end of the day is available; disagreeing: travelling sales people and commercial reps for whom time is money).
By contrast the best-case for current gen Tesla Roadster roadtripping of 160 miles followed by 240V 40-70A recharge (10-17 kW) requires 2.5 to 4.5 hour breaks after 2-3 hours of driving. This ratio of 1:1 to 1:2 drive:rest falls short of my patience threshold. I totally appreciate the pioneering efforts of people in the Tesla Owners community in this regard, but I think the vast majority of people won't accept the resulting travel times for long drives.
If the Roadster incorporates the RWE 43kW standard in future and the German autobahn network (and hopefully other countries networks' around Europe as well) are equipped with 43kW chargers every 100 miles or so, then the Tesla Roadster will be a joy to drive across Europe.
On the utility side, 400V 3-phase 63A (43 kW) is easy for utilities like RWE to deliver to just about anywhere on their grid. Motorway service stations defintely have it.
2. Consider installing such 43 kW chargers at all the usual opportunity charging locations (malls, cinemas, restaurants, public buildings, ...). This solves the other problem: what to do for the millions who live in apartment building who park on street.
We all know the stats that say 90% of driving is less than 40 miles per day. If an EV does 160 miles between charges for city driving, and then re-fills in an hour, then 90% of drivers won't have to charge more than once every 4 days or twice a week. (Many drivers who do fewer miles per day will be fine charging weekly or fortnightly for around town driving.)
An hour charge while at the cinema, gym, supermarket is absolutely fine.
On the utility side, installing thousands of 43 kW chargers in concentrated locations like malls where 400V 3-phase is readily available, is a darned sight easier than ripping up thousands of miles of city streets to equip millions of parking spots with slow (overnight) chargers. (Broadly I estimate that one 43kW at a mall can substitute for around 30 kerbside overnight chargers, and in the early adoption phase gets a far higher leverage factor - ask for details if interested.)
RWE and their consortium partners have been careful not to disenfranchise cars that charge more slowly. They allow single phase up to 70A. I think utilities will easily be able to manage the unbalanced load issues on single phase use of the chargers in public places like malls where vehicle charging is just one of many uses of their electric grid.
To conclude:
To my mind the RWE/Mennekes charging standard allows EVs to be built that allow reasonable time long-distance driving and easy use for city dwellers without private parking.
This is breakthrough territory.
It allows someone to think of buying an EV as their only car, no longer needing either a second car ICE to cover occasional road trips or a PHEV. And it allows EVs to be used by apartment dwellers with a broadly familiar mode of use (park on the street without charging, fill up at the supermarket every so often - in Europe supermarkets already have gas stations and sell a lot of fuel. )
I don't see this as the final end-point - higher charging kW profiles will follow, but this standard crosses a threshold. It does it with standard power already delivered all over the place in Europe; low-cost infrastructure and plugs; cable and sockets capable of being used by anyone.
Andrew Bissell (copyright and republication rights reserved)
1. How to drive a long distance down the autobahn in a single day on the occasions when I need to.
2. How the millions of apartment-dwellers should recharge routinely.
RWE have addressed this by choosing to offer up to 400V 3-phase 63A for recharge. This delivers a 43 kW charge rate.When combined with around 50kWh batteries (in the model of Tesla) the impact is game-changing.
Consider a car with the range of the Tesla Roadster (200 miles Range Mode with the central 160 miles routinely used in Standard Mode). Those central 160 miles use 80% of 53 kWh ~= 43 kWh. So on a 43kW charger the Roadster could in principle recharge 43kWh in an hour (ignoring charging losses) or 160 miles range per hour.
Note: this combination doesn't exist yet because Tesla doesn't support 3-phase charging.
Nevertheless RWE are taking a bold step of the "if you build it they will come" variety. And in my view they have found a sweet spot that manages to exceed a new threshold of user acceptance and yet is within the capability of utilities to deliver cost-effectively.
What are the implications of 160 mph charging?
1. You can cruise down the autobahn/motorway/interstate for 2-2.5 hours, covering around 160 miles, then take a one hour break for comfort and recharge, then cover another 160 miles, another 1 hour charge and comfort break, and repeat ad infinitum. (or variants like drive 100 miles, charge 40 minutes, repeat)
To me this 2:1 drive:rest ratio seems entirely acceptable. I think a large fraction (but not all) of the population would agree (agreeing: those who roadtrip less often and when they do drive up to 500 miles per day requiring just two intermediate 1 hour breaks assuming charging at either end of the day is available; disagreeing: travelling sales people and commercial reps for whom time is money).
By contrast the best-case for current gen Tesla Roadster roadtripping of 160 miles followed by 240V 40-70A recharge (10-17 kW) requires 2.5 to 4.5 hour breaks after 2-3 hours of driving. This ratio of 1:1 to 1:2 drive:rest falls short of my patience threshold. I totally appreciate the pioneering efforts of people in the Tesla Owners community in this regard, but I think the vast majority of people won't accept the resulting travel times for long drives.
If the Roadster incorporates the RWE 43kW standard in future and the German autobahn network (and hopefully other countries networks' around Europe as well) are equipped with 43kW chargers every 100 miles or so, then the Tesla Roadster will be a joy to drive across Europe.
On the utility side, 400V 3-phase 63A (43 kW) is easy for utilities like RWE to deliver to just about anywhere on their grid. Motorway service stations defintely have it.
2. Consider installing such 43 kW chargers at all the usual opportunity charging locations (malls, cinemas, restaurants, public buildings, ...). This solves the other problem: what to do for the millions who live in apartment building who park on street.
We all know the stats that say 90% of driving is less than 40 miles per day. If an EV does 160 miles between charges for city driving, and then re-fills in an hour, then 90% of drivers won't have to charge more than once every 4 days or twice a week. (Many drivers who do fewer miles per day will be fine charging weekly or fortnightly for around town driving.)
An hour charge while at the cinema, gym, supermarket is absolutely fine.
On the utility side, installing thousands of 43 kW chargers in concentrated locations like malls where 400V 3-phase is readily available, is a darned sight easier than ripping up thousands of miles of city streets to equip millions of parking spots with slow (overnight) chargers. (Broadly I estimate that one 43kW at a mall can substitute for around 30 kerbside overnight chargers, and in the early adoption phase gets a far higher leverage factor - ask for details if interested.)
RWE and their consortium partners have been careful not to disenfranchise cars that charge more slowly. They allow single phase up to 70A. I think utilities will easily be able to manage the unbalanced load issues on single phase use of the chargers in public places like malls where vehicle charging is just one of many uses of their electric grid.
To conclude:
To my mind the RWE/Mennekes charging standard allows EVs to be built that allow reasonable time long-distance driving and easy use for city dwellers without private parking.
This is breakthrough territory.
It allows someone to think of buying an EV as their only car, no longer needing either a second car ICE to cover occasional road trips or a PHEV. And it allows EVs to be used by apartment dwellers with a broadly familiar mode of use (park on the street without charging, fill up at the supermarket every so often - in Europe supermarkets already have gas stations and sell a lot of fuel. )
I don't see this as the final end-point - higher charging kW profiles will follow, but this standard crosses a threshold. It does it with standard power already delivered all over the place in Europe; low-cost infrastructure and plugs; cable and sockets capable of being used by anyone.
Andrew Bissell (copyright and republication rights reserved)
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Obviously it's fun to speculate, but I presume the circuit or cooling of the PEM could be beefed up to handle this (and the latter would have to be done for a separate circuit anyway).
The Mennekes plug can deliver a very similar amount of power to that which I have seen quoted for regen (44 vs. 40kW)
TEG said:
How does the PEM do it now (or how did it with reductive charging in the old design)?
Yes, 230V <16A outlets form the vast majority of outlets as they are the default domestic ones. They are also found on the majority of today's on-street charging stations.
That's fine for small cars like NICE and G-Wiz, but for high-power EVs like Tesla's it isn't. As you know, even for an overnight charge the car needs >30A. The issue is that some power companies don't like this happening on a single phase as AlpineDriver has found.
Furthermore, even where it isn't requirement, these sockets still exist. I know of even industrial installations in the UK where the main board is 63A 3P. You couldn't run the HPC from one of the phases, yet there is more than enough power available to do a fast charge.
Joseph said:Tt doesn't sense that all European EVs would have the same connector even though not all European EVs would charge charge from three-phase/single-phase.
Diesel stations have different nozzles than gasoline stations, shouldn't it be the same for single-phase vs. three-phase charging?
Shouldn't the connectors be different to avoid the balancing issues you guys were talking about at the beginning of the thread?
I suppose the difference between diesel/gasoline and 1P/3P is that you can put more intelligence into an electrical connection. The Mennekes-equipped charging station, cable and car will be able to work out which is the weakest link in the chain and charge at that component's fastest rate. It means that average users only have to carry one cable, not bother about things like volts and amps and only worry about how long they have to leave their car on the charger (something I'm sure will be communicated in a user-friendly manner).
Larger charging stations like the 3P Elektrobays and the RWE ones that we have seen will probably have to do balancing internally. Others can tell the car their requirements.
However, this scenario is a while away. In the meantime the trailblazers will have to carry a multitude of plugs and do this themselves - just like in the US - with the added complication that you might want to scavenge (or even charge at home) from a 3P source.
EDIT: Andrew posted in the meantime - 100% agreed.
P.S. It should be remembered that this Mennekes design is not officially a standard. It appears to be their proposal for a new IEC standard which is at least a year away from ratification. Clearly, announcing it as such is a political move designed to railroad their design through. As a "standards" person, this kind of thing normally annoys me, but in this case given that 1) it appears to be well thought out and 2) time is of the essence, I will forgive them :smile:.
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Assuming that you and your immediate neighbours have a daily commute/range need of around 200 miles and share a similar taste in cars.
In an average neighbourhood we can expect a mixture of BEV and plug-in hybrids. So we could see a wider range of required currents/ charging habits.
However, the Friday night recharge-for-the-weekend could be the issue.
Maybe a Smartgrid could improve phase balancing? Or 3P is fitted as standard in new garages.
If your neighbours have the same cars and range requirements, the problem goes away :wink:
A smart grid could help, but it requires a lot more EVs to be in the field to improve the chances of other local ones being on different phases.
If we rearchitected local distribution into a star topology, so that the substation could switch individual houses onto different phases as necessary, it could help - but what are the chances of that? :frown: I guess you could have 3P into the garage and use a remotely controlled transfer switch to select between phases, but if you have it there it seems silly not to send it straight to the car and get the 3P benefits.
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