New EV charging system.

[Raebrek]

I was watching a YouTube video on Munro Live and a reference was made to a new charging system for EV’s. I watched the video and then thought…. Where can I share this. This forum seems like a good place. Enjoy and let me know your thoughts. Hey, it’s all over my head.



New EV Inverter Slashes Charging Time - CES 2023

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[Crissa]

You don't use inverters to charge batteries. So the title is weirdly wrong, in the beginning. Inverters invert, that is, create the alternate in alternating current (AC). Battery cells are charged with DC (direct current).

-Crissa

 

[Bill906]

Wow that video was hard to watch. Lots of patting themselves on the back and telling us how good they are without giving any real details on what it is they are doing...

You don't use inverters to charge batteries. So the title is weirdly wrong, in the beginning. Inverters invert, that is, create the alternate in alternating current (AC). Battery cells are charged with DC (direct current).

Although most people think AC -> DC is a converter (or rectifier) and DC -> AC is an inverter... that is usually true, but not always. An inverter can work both ways. For example, when your Tesla is slowing down and regenerating, it is taking AC power from the motor, and converting it to DC and charging the battery. I THINK that is what these two are talking about. Instead of having a separate converter for charging, use the inverter that is already there. But I'm not sure as they only seemed to want to tell us how great of a job they did, and not telling us what they did. If that is in fact what they are talking about, I don't see that as a great revelation they make it out to be. I feel very confident in assuming Tesla engineers had already thought of it, weighed the pros and cons, and decided not to do it. I could be wrong in that assumption, but I don't think so.

 

[android04]

Wow that video was hard to watch. Lots of patting themselves on the back and telling us how good they are without giving any real details on what it is they are doing...



Although most people think AC -> DC is a converter (or rectifier) and DC -> AC is an inverter... that is usually true, but not always. An inverter can work both ways. For example, when your Tesla is slowing down and regenerating, it is taking AC power from the motor, and converting it to DC and charging the battery. I THINK that is what these two are talking about. Instead of having a separate converter for charging, use the inverter that is already there. But I'm not sure as they only seemed to want to tell us how great of a job they did, and not telling us what they did. If that is in fact what they are talking about, I don't see that as a great revelation they make it out to be. I feel very confident in assuming Tesla engineers had already thought of it, weighed the pros and cons, and decided not to do it. I could be wrong in that assumption, but I don't think so.

Also, the regen power from the motor is coming into its inverter as 3 phases. Even if they repurpose that drive inverter for use as a charger, they can only use 1 or 2 of the phase circuitry to charge in a household (in North America).

Also, it seems a lot of the technical info is dumbed down or wrong. They state at the very beginning that this system can charge 3x faster than a regular one, but don't give specifics on if it means to do this by using 240VAC at 16A? versus a typical 120V @ 12A. They are definitely not going to charge 3x faster from the same type of outlet...

Edit: Perhaps they can use the 3 phases of the inverter redundantly in order to handle higher power charging. IIRC, the Tesla Model 3 inverter can send the battery up to around 80kW for brief periods of time.

 

[Bill906]

SIngle phase vs. three phase isn't that big of a deal. It can easily be designed to take in either.

But yes, the few numbers and specs given either weren't given the explanation needed, or was just flat out gibberish, or most likely, a little of both.

 

[TyPope]

Some New Thing you MUST SEE NOW!

 

[Bill906]

Some New Thing you MUST SEE NOW!

One thing everyone agrees on. Rockwell Automation makes the best Retro Encabulator. Hands down!

They also make some awesome variable frequency drives. I've worked with a lot of them.

 

[Crissa]

Although most people think AC -> DC is a converter (or rectifier) and DC -> AC is an inverter... that is usually true, but not always. An inverter can work both ways. For example, when your Tesla is slowing down and regenerating, it is taking AC power from the motor, and converting it to DC and charging the battery.

...but then the inverter is rectifying the current.

The only reason to use an inverter this way is if you're converting a two-way flow of energy. It won't charge the battery faster, unless there is something specific about the battery chemistry (like NiMHs can be quick-charged with pulsed current). And even then, inverters have components a rectifier doesn't need.

-Crissa

 

[Bill906]

...but then the inverter is rectifying the current.

The only reason to use an inverter this way is if you're converting a two-way flow of energy. It won't charge the battery faster, unless there is something specific about the battery chemistry (like NiMHs can be quick-charged with pulsed current). And even then, inverters have components a rectifier doesn't need.

-Crissa

Completely agree.

I was just trying to make sense out of what the guys were saying. I THINK what their great idea was, is to remove the rectifier normally found in EV's and instead use the existing inverter as a rectifier. Removing a part. If that is what they were saying, I don't know how they plan on doing it. In a very oversimplified way, an inverter has DC connection on one side and an AC connection on the other. In an EV the DC is connected to the battery, AC side connected to the motor. (In this oversimplified example, let's ignore single phase vs. three phase). If my assumptions on what they want to do is correct, I'm curious how they plan to switch from having the motor connected to the AC side of the inverter when the car is moving, to having the AC Utility power connected to the AC input on the inverter when charging.

Also, Not sure how the inverter, when used in this manner, will be able to handle different charging voltages (i.e. 120VAC vs 240VAC). But I won't get into that part here.

I have no idea how they plan on making the charging faster.

 

[Raebrek]

As I said at the top, this all over my head.
Maybe this adds more insight.

Eleap brochure.

 

[fhteagle]

I read the brochure. From what I could pick out from between the marketing speak, this seems to be the same or very similar to the Wunderbox in Lucid Motors vehicles.

 

[Bill906]

I read the brochure. From what I could pick out from between the marketing speak, this seems to be the same or very similar to the Wunderbox in Lucid Motors vehicles.

Just watched this. Little long but had some good stuff in it.

I was wondering how 900VDC systems were going to work. Here's some questions I had that the video answered:

• Does the motor/inverter run off 900VDC, or is the DC voltage lowered to the typical 400VDC?
  • According to that video, the motor/inverter in the Lucid are designed to work off the 900VDC.
• Can the battery be charged from a charger limited to 400VDC output? If yes, how?
  • The Lucid can be charged from a 400VDC charger. It does it by using a DC to DC converter, not by changing the battery connections to reconfigure battery modules from a series to a parallel configuration.

 

[JBee]

Looks like they are using the motor inductance as a transformer along with motor controller for variable voltage input /output at pack level power ratings. The key is their power factor control (lead/lag), but it will only work on induction motors really not PM.

The cool thing is they have removed a specific charger circuit, and can do 1/3phase both in and out of the pack at full power. So not only faster charging, but also full power V2X.

 

[CyberGus]

Some New Thing you MUST SEE NOW!

One thing everyone agrees on. Rockwell Automation makes the best Retro Encabulator. Hands down!

They also make some awesome variable frequency drives. I've worked with a lot of them.

Milwaukee manufacturer Rockwell Automation capturing strong share of auto transformation
https://www.bizjournals.com/milwaukee/news/2023/01/13/rockwell-automation-ev-electric-vehicles.html

I can't tell if news is real anymore

 

[Bill906]

Milwaukee manufacturer Rockwell Automation capturing strong share of auto transformation
https://www.bizjournals.com/milwaukee/news/2023/01/13/rockwell-automation-ev-electric-vehicles.html

I can't tell if news is real anymore

Cool. I’ve been to their Mequon plant. It’s real.

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