ricinro

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I have not gone in the weeds researching this... but part of the infrastructure bill is building out charging stations or at least subsidizing the construction of charging stations.
If there were consultations with EV charging station providers (like Tesla) I am sure the EV charge companies were told that the gov't could not fund proprietary systems. So it would either mean a US standard for plugs (not likely) or provide adapters at charging stations -access for all EVs.
Also, there would need to be rules limiting rate gouging.
I could see why Tesla could be interested in federal funding: They could easily/quickly mass produce charging stations and open them up to all EVs with a tethered adapter(s). Sure, Tesla could make a slight profit but more importantly they could saturate the country as well if not much better than other Charger companies. Considering that range anxiety, time to charge, and availability of chargers are major concerns to folks considering the switch to EVs, this really would accelerate the transition...
I currently have a Y LR in AZ and there have been trips where there are no Superchargers. Being able to charge using Electrify America or others in far flung places and not paying a penalty $$$ makes charging as easy as finding a gas station.
BTW we were considering a trip to Roswell NM but the range issue disallowed it. Skinny Bob will need to wait a few years.

P.S. Just read an article where 7.5 billion is in the Infrastructure package for EV charging stations.
 
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Crissa

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BTW we were considering a trip to Roswell NM but the range issue disallowed it. Skinny Bob will need to wait a few years.
The trick is to find an RV park where you can plop down with a NEMA 14-50 and suck down juice for an hour or overnight. There are many, and lots will let you plug in free.

-Crissa
 

Crissa

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AC charging is phase related but AC converted to DC and with DC the best and the quickest charging so there is no DC phase 2 or 3 or ?? all that goes away with the better DC fast charge
DC charging standards differ between North America, Europe, China, and Japan.

And DC chargers are quite expensive right now. They do take the equipment off the vehicle, and allow direct building access to the battery, so eventually they are the way to go. But that is currently a future thing.

-Crissa
 


ajdelange

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AC charging is phase related but AC converted to DC and with DC the best and the quickest charging so there is no DC phase 2 or 3 or ?? all that goes away with the better DC fast charge
Not sure whether this is a statement or a question. Currently (no pun intended) electricity in most of the world is delivered as 3 phase AC. A battery is a DC device. It must be charged with unidirectional current, thus the AC must be "rectified". A battery charger must, at a minimum, do this rectification but it also must be able to regulate the DC voltage in response to commands from the car and isolate the car from the mains supplying the AC. To do this it first turns the alternating positive and negative mains pulses into all positive pulses. Label the wires coming into the rectifier A and B. Rectification is a simple matter of swapping A and B in synchronism with the mains reversal rate (50 or 60 times a second). A is switched to the positive terminal of a capacitor when A is positive relative to B and B is switched to the positive terminal when B is positive relative to A. Thus the capacitor is charged to a voltage which is always of the same polarity. Second step is to run this DC through a second set of switches to chop it up into square pulses of alternating polarity at a rate in the 10's of kHz. The resulting square wave is passed through a small transformer (small because the frequency is high) which does the isolation function and the output is again rectified by charging a capacitor unidirectionally. This cap is connected to the car battery. The car controls the current going to the battery by asking the charger to increase or decrease its output voltage which it does by varying the width of the square pulses it generates in the chopper in front of the transformer.

The charger is a box that sits in the fender well of the car near the charge port. When charging at home in north America you connect the charger to the 240 V mains. When charging at a SC you don't use the charger in the car. You use a bank of interconnected chargers in a cabinet behind the fence near the terminals. These chargers were rumored at one time and appeared to be identical to the chargers used in the early Model S. They are connected to the output of a stepdown transformer connected to the distribution mains which are three phase i.e. they have 3 wires, A, B and C going into and coming out of the transformer. The chargers are arranged in multiples of 3 in which one is connected to A and B, one connected to B and C and one connected to C and A. The outputs are connected in parallel to the pins on the charging wand. Obviously there is more than one chargers triplet in a cabinet and so the total current delivered to the battery is in the hundreds of amperes rather than the tens delivered by the single charger in the car.

In many parts of the world distribution to residences is three phase. In those countries Tesla sells cars with 3 rectifier modules in the vehicle itself. The wand has 3 input power pins and the 3 modules connect, as at the SC station, AB, BC, CA.

In summary, it doesn't matter whether you charge at home or an SC. The same process is going on involving hardware which is at least functionally the same. Energy from the mains is converted to energy in a form the battery can take. Since the dozens of chargers in the cabinet can supply more current than the single charger in your car can charging is faster.

If the post was a question, I hope I answered it.

I should note that I have never seen any Tesla documentation nor taken apart a charger module from a car or SC. What I have set forth here is what I have gleaned from looking at videos in which others have taken charging modules apart, what I can see peering into the fenced area at SC stations, my experiences working in a rectifier factory and general EE knowledge.
 
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ajdelange

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Who makes the best EV chargers?
Not quantity but quality and not home but public use chargers.
Easy of use
Speed of charge
Less repair break down more robust.
The more relevant question is who has the easiest to use, most reliable charging system and the clear answer is Tesla. There is more to the system than the charger itself. The way it is managed and maintained is a large part of it. Some of the other manufacturers make chargers that are probably as robust as Tesla's but, at least in the US, no operator seems to have proven itself capable of integrating these into a system. Check out some of the interviews with the president of EA. In them he describes some of the problems many of which stem from using chargers by different manufacturers in a single network and many of which relate to problems getting the credit card readers etc to integrate. Tesla's payment system is clearly head and shoulders above any system that uses RFID cards, phone apps or credit cards.
Sponsored

 
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