panel to EV direct

[5trsth]

If you want to charge your ev car with your own panels it seems you have to go with a grid tie system and basically credit yourself for the watts you take off the grid. But if you you want to go direct to your EV and its onboard charging system you have to give it AC and it will convert and charge for you. But how to do it without batteries.. I am surprised to see that no one makes a
controller/Inverter that will accept 150-300VDC and gives you the option to use the AC at max watts right out of the unit. The inverters that accept variable DC in are all grid tie and very expensive.
Another option would be a DC to DC converter but I don't think any EVs would accept that ,none I know of will accept DC direct to the batteries.t..they want AC so they can convert it exactly for their batteries and charging regimes in the EV.
There must be an option...how can I find a solution for this??I want variable DC,mppt, to 240v AC and thats it.It shouldn't be too hard to design that..???? Where is something like that??

[bcroe]

There must be an option...how can I find a solution for this??
I want variable DC,mppt, to 240v AC and thats it.It shouldn't be too hard to
design that..???? Where is something like that??

If you ever actually had to design such equipment, you would find it
is not so simple. The big initial problem is,that renewable energy is
so un predictable. Batteries are a way to help that. Bruce Roe

[Ampster]

If you want to charge your ev car with your own panels it seems you have to go with a grid tie system and basically credit yourself for the watts you take off the grid. ..........
There must be an option...how can I find a solution for this??I want variable DC,mppt, to 240v AC and thats it.It shouldn't be too hard to design that..???? Where is something like that??

I have two EVs and I have looked. The most cost effective option right now is a grid tie system to charge your EV at off peak rates.
If you want to explore the other options tell me how many kWhs a week you want to charge your EV and whether it can be in your driveway or garage from 9 AM until 4PM?. If you can't be there every day tell me how many days you can charge? I would be happy to discuss the issues I have discovered in trying to find a solution. The type of EV you have would also help in framing the issue.

[5trsth]

In my case I can leave my EV outside the house for 4 days at a time.5 ft from the panels. Regarding the comment from bcroe...My Midnight Solar controller already does a good job turning 150vdc
into 48 vdc. From there it would only require a switching transformer to make low grade wave AC 120. I don't think onboard chargers care if the wave is perfect because they convert to DC anyway.
Now,I have a 300 watt inverter but thats not enough power. It would have to be at least 1500 watts to be useful.But I don't want or need a battery set up.And cycling a battery that hard cant be
good for it.I would wear it out pre maturely.If some college EE students would look at this need for a simple controller/charger like described here ..I am sure they could come up with something.
If someone on this forum is one of those students please give this some thought.

[Mike90250]

........I would wear it out pre maturely.If some college EE students would look at this need for a simple controller/charger like described here ..I am sure they could come up with something.
If someone on this forum is one of those students please give this some thought.

It's only simple when you don't understand the complexitys involved.

Likely the simplest is to wire your panels for ~ 300V DC, and plug into the battery bus and sit there with a voltmeter and switch it off when batteries are full. But I wouldn't do it

[SunEagle]

In my case I can leave my EV outside the house for 4 days at a time.5 ft from the panels. Regarding the comment from bcroe...My Midnight Solar controller already does a good job turning 150vdc
into 48 vdc. From there it would only require a switching transformer to make low grade wave AC 120. I don't think onboard chargers care if the wave is perfect because they convert to DC anyway.
Now,I have a 300 watt inverter but thats not enough power. It would have to be at least 1500 watts to be useful.But I don't want or need a battery set up.And cycling a battery that hard cant be
good for it.I would wear it out pre maturely.If some college EE students would look at this need for a simple controller/charger like described here ..I am sure they could come up with something.
If someone on this forum is one of those students please give this some thought.

I see the problem with a new tech DIY as being in conflict with insurance and warranties. If you go forward with this "solution" you may end up hurting your EV, panels, or the new tech device and get no help from anyone that made them. Your choice to pursue it further but IMO I would just look into a grid connected system and charge the EV from your home AC panel.

[Ampster]

In my case I can leave my EV outside the house for 4 days at a time.5 ft from the panels. Regarding the comment from bcroe...My Midnight Solar controller already does a good job turning 150vdc
into 48 vdc. From there it would only require a switching transformer to make low grade wave AC 120. I don't think onboard chargers care if the wave is perfect because they convert to DC anyway.
Now,I have a 300 watt inverter but thats not enough power. It would have to be at least 1500 watts to be useful............

As SunEagle mentioned accessing the high voltage battery could void the EV warranty, not to mention having high voltage DC near a structure. To charge directly with DC you would need to intimately understand the characteristics of the battery in your car. Assuming your EV battery is at least 300 VDC you would have to increase the number of solar panels or reconfigure them to produce more than that for any efficient DC to DC converter to work. Boosting 150 volts to 400 volts is not going to be efficient and as the current capacity increases the price will go up significantly. That is just the hardware part and you would have to decide if that expense to do a DC solution was better that focusing on an AC solution where the hardware is readily available at reasonable prices. T

Interfacing with the onboard BMS would be important so presumably CANBUS skills would be required. An acquaintance, who once owned a RAV4EV made some money adding a Chademo fast charging capability to those cars but the product cost several thousand dollars including installation. He was fairly knowledgeable about the battery pack in that car, knew CANBUS and had to learn the Chademo fast DC charging protocol. . It was not trivial to come up with a design that worked. I asked you earlier but got no answer to the question abut what EV you owned?
My EVSEs are very sensitive to incoming power and there is a Ground Fault Circuit device inside, so I am not sure the simple rectifier would work.

I think I can dial down my onboard charger pretty low. Without knowing what EV you have it is hard to offer much advice about a simple solution. 1500 Watts at 120 volts is 10 Amps. Do you have enough solar panels to generate 1500 Watts? That is the operative question because the onboard charger has some overhead and you have to have enough capacity to overcome that.
I have a grid tie system and it is easy for me to just plug in during the day. What are you using the energy for that your solar panels generate now?

[5trsth]

I have 2KW of panels. I don't use them at the moment. ok say the AC sine wave is the only way to go. Is there a way to trick a grid tie inverter like the SMA 3000 watt ..by providing some AC
from a battery pack/inverter(they won't turn on unless they sense 240 ac) in order to get access to the AC that it would send to the grid..?? but take that to the car instead??
My EV will likely be a Hyundai 2023 or a Chevy 2023...around the 35K $ range.240 mile range.approx.

[Ampster]

I have 2KW of panels. I don't use them at the moment. ok say the AC sine wave is the only way to go. Is there a way to trick a grid tie inverter like the SMA 3000 watt ..by providing some AC from a battery pack/inverter(they won't turn on unless they sense 240 ac) in order to get access to the AC that it would send to the grid..?? but take that to the car instead??

There is no way to trick a Grid Dependant Inverter.(GT Inverter) with just "some AC". The GT inverter uses a number of tests to make sure it has a grid connection. I use a hybrid inverter to do what is called AC coupling and it is not a trick but a complex algorithm for a hybrid to control a Grid Dependant Inverter. That type of hybrid in a tier 1 quality like my Outback Skybox is about $2500. You may be able to find some that are less expensive but almost all of them need batteries to provide some buffer so they can AC couple. It is not the simple process that it would appear to be on the surface.

My EV will likely be a Hyundai 2023 or a Chevy 2023...around the 35K $ range.240 mile range.approx.

My suggestion is that if you do not already have a 30 Amp receptacle near where you will park your EV , that you get one wired. My perception changed about charging an EV at home changed after the first few weeks. So trying to conceptualize a plan without experience will lead you down some paths that end up no where relevant. The impact in kWhs changed after I got my first bill but I already had 2700 Watts of solar so I was already thinking in kWhs. Then you will have sufficient data to evaluate the financial benefit of installing more panels and a modern GT Inverter. GT inverters can be as inexpensive as $1000 but if you want to start out small you could buy enougn micro inerters for your existing panels unless you already have a GT inverter.

[solardreamer]

If you want to charge your ev car with your own panels it seems you have to go with a grid tie system and basically credit yourself for the watts you take off the grid. But if you you want to go direct to your EV and its onboard charging system you have to give it AC and it will convert and charge for you. But how to do it without batteries.. I am surprised to see that no one makes a
controller/Inverter that will accept 150-300VDC and gives you the option to use the AC at max watts right out of the unit. The inverters that accept variable DC in are all grid tie and very expensive.
Another option would be a DC to DC converter but I don't think any EVs would accept that ,none I know of will accept DC direct to the batteries.t..they want AC so they can convert it exactly for their batteries and charging regimes in the EV.
There must be an option...how can I find a solution for this??I want variable DC,mppt, to 240v AC and thats it.It shouldn't be too hard to design that..???? Where is something like that??

If you just want solar power to go directly to EV then you can use PV capable EV chargers like these:

https://www.dcbel.energy/r16/

https://enteligent.com/solar-fast-ev-charger

[5trsth]

would the micro inverters be any different???
above...the Enteligent still needs a grid tie...
I suspect someone will come up with a solution for PV direct charging soon...it makes sense...

[Ampster]

would the micro inverters be any different???
above...the Enteligent still needs a grid tie...
I suspect someone will come up with a solution for PV direct charging soon...it makes sense...

Micros are just another GT inverter.
Makes sense? Wait until you have driven an EV for a few months and see if it makes sense? Do the math on the number of kWs of panels or the price of one of the above DC fast charging options and see if it makes sense compared to just plugging into a 30 or 50 Amp circuit? To get any benefit from a DC charging station you probably need a 100 Amp circuit. I know a lot of people who drive EVs and none of them want a DC charging solution. I definitely would make sure the EV you purchase has the DC fast charging option for road trips though.

[solardreamer]

would the micro inverters be any different???
above...the Enteligent still needs a grid tie...
I suspect someone will come up with a solution for PV direct charging soon...it makes sense...

Perhaps you got confused by the typical deployment diagram, Enteligent does not require a grid-tied inverter for charging EV from PV panels. The diagram just shows how it can integrate with a grid-tied inverter since typically people want to take advantage of net metering.

[5trsth]

he seems to be right about Enteligent....it says they are launching a solar charger this fall 2022. It seems to be exactly what I am talking about. But not much info on their site and no contact and from California so who knows... I assume its a variable DC to AC 120/240v unit....maybe one of their people could comment if they see this..if its real and the price isn't stupid...might be a solution.
We Definitely don't need a sky high priced unit..

[Ampster]

..it says they are launching a solar charger this fall 2022. ......

I did not see a page about the solar charger. Are you coming the DC Fast charger with a solar charger? I did see the page about the DC Fast Charger that they plan to release in the Fall of 2022. It is bidirectional so the use will be for Vehicle to Home or Grid. I assume it runs from AC like all other chargers or charging equipment.