3 phase charging at home

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Zwerius

Well-known member
Joined
May 26, 2013
Messages
77
Location
Ootmarsum, The Netherlands
Hello,
I have an i3 with range extender. No fast charging option.
99.9 % of the charging is done at home, with the supplied 230V single phase charger.

Since my wife also has an electric car for about half a year now (VW E-UP), we sometimes draw a serious amount of power from the grid.
The car's are not charged at the same time, because of the risk of blowing up the main fuse(s).

We have a 3 phase connection to the grid, with main fuses of 3 x 25A.
Keep in mind that we als use a heatpump for heating and have several appliances in the house.

I would like to divide the charging current (10A) over three phases.

Does anyone of you know about a charger, that has a 3 phase input, but is charging the car through a Mennekes (type2) connector with only a one phase connection?
I could imagine, it could be possible to make DC from the 3 phases and supply the DC to the car over a single set of wires (+ and - in stead of L aand N).
Do these type of chargers exist? Or could i build one myself?
 
The DC fast chargers generally use 3 phase AC supply, but at a minimum of 480 volts. The 150 KW DC chargers will use even higher voltages. I recall that one of the EVSE manufacturers (Juicebox) offered a DC charger "kit" at one time. I really think you are overthinking with this approach.
 
Just to be clear: it's not ment to have high charging power available, but only to distribute the power evenly over the three phases. So that the power drawn (per phase) is lower than when it's all coming from one phase. The 2.3 kW charging power i'm using now (10 Amps at 230V) is sufficient for me.
For your information: our powersupply is 230/400V.
 
European i3 drivers would need to assist you with an answer. We North American i3 drivers are electricity phase-challenged :D Residential electricity is typically 240 V split phase (i.e., 2 120V phases 180º out of phase with each other). Our apartment has 3-phase 277 V commercial electricity, but each apartment gets only 2 120 V phases 120º out of phase, or 208 V between phases.

Those of us charging at 120 V might want to be able to balance the charging power between our 2 phases if we feared overloading one of the phases, but I'm not aware of any EVSE that does this. Maybe some 3-phase European EVSE has this capability. Good luck!
 
If you had a DC input, you'd need a very significant dc power supply, and some computer logic circuits to communicate with the car. There isn't any cheap way to use 3-phase power and feed the single phase power supply in the car. Without the internal DC fast charging circuit in the car, you're limited to ACV inputs.

A pure sinewave UPS that output a single phase with a 3-phase input could do it, but I'm not familiar enough with what's available in Europe to know if they even make one. One large enough to feed the car would not be inexpensive.
 
There are solutions that do a phase coversion or even ones that will provide DC charging from multiple phases.

Not sure if I can link those directly to post but MDC22 is a mobile charging solution with DC capability and Accelev one with phase conversion from multiple phases to single phase car charger.

https://www.designwerk.com/en/mobile-dc-charger-22-kw-mdc22/
https://emobe.eu/en/shop/accelev-5-kw-6-kw-3/

Price level is still somewhat have highish but solutions are there and prices will drop when competition increases.
 
His vehicle doesn't have the DC fast charging receptacle, so a DC input is not viable. I guess a thousand + Euros might be a bit much but if you need it, I guess you need it for an acv option. STill, using only two phases won't fully balance a 3-phase load.
 
D.C. Chargers are uber expensive. When I last looked some 6 moths ago, I could get one installed for around $10,000

But you might want to look it a different way. Without fast D.C. charging, if you want to charge two EVs at the same time, you need two chargers.

Why don't you get two 'connected' EV chargers where you can set the time when you start charging? Example: set charger 1 for 10pm to 2am and charger 2 for 2am to 6am. There are of course two downsides to this approach. If the chargers for some reason try to turn on at the same time, you will pop a circuit breaker. Second, you need to plan how many hours each car needs to charge.

The newer Tesla home chargers can be daisy chained for multiple EVs, but as far as I know, none of the other home EV chargers can be daisy chained.
 
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