Okay, thanks for being here.
Today I want to talk about bi-directional charging.
About the protocols, the challenges and the strategies we do in Evers.
My name is Andreas. I'm working at Pionics on Evers.
As I said, we will start what bi-directional charging is and why we should do it.
Then some different charging and discharging strategies.
And then we will have a look at the entire impact chain of it.
And then I will give you some insights and Evers how we do energy management there.
And then we will come to conclusion.
So what is bi-directional charging? I guess you all know what charging is.
And I guess you all know what this charging is.
And if you put both together, you have bi-directional charging.
So with this, why should we do it?
That different reasons for it.
At first, there was a climate change.
This is why we have renewable energies with small producers and decentralized production.
And this is why we need grip stabilization.
For this, we can use electrical vehicles.
And some personal motivations could be the price optimization during the charging.
And you could also use your EVS emergency power supply.
Or just use the EV as a big power bank, for example, at the camping ground.
And then we will start with a very first charging strategy.
For this, we need an electric vehicle with a certain minimal and maximal charging power.
And a specific battery size.
And the goal is to charge this EV as fast as possible.
And strategy is okay.
You just take as much as possible available power to charge the car.
And in this scenario, we have an external restriction of charging power after 30 minutes.
So you can see the result here.
The green line, the charging power, which starts with 50 kilowatts.
And then drops after 30 minutes to 20 kilowatts.
Because of this external limit.
And yeah, after 30 and half hours, the EV is full.
And the charging session ends.
So quite easy straight forward, strategy.
The more complex one is the optimization of the PV produced energy consumption.
And also with some other consumers in the local grid.
For this, we need a photovoltaic system, which has certain peak power and daily energy yield.
And the curve.
So the most energy production will be around 12am.
And again, we have a scenario.
The arrival time is at 11 o'clock.
We have a state of charge of 10 kilowatts and a max charging power of 20 kilowatts in this scenario.
And goal is to use as much of the PV produced energy as possible.
And strategy is that we calculate the left over at the grid connection points.
So we have the PV production, subtract the other consumers.
And with this left over power, we can charge.
And if this left over power is negative, we can discharge this left over power to come to zero at the left over energy.
So here, the result again in the upper left, you see the PV production in purple.
And yellow, some random other consumers.
And then bottom left, you see the left over energy.
And you can see, until 11am, we have some import of energy in the beginning.
And then some export of energy.
And at 11am, it drops to zero.
And this is because, which you can see in the upper right, the charging power starts at 11am.
The PV arrives and starts to charge and brings this left over energy to zero.
And at a certain time around 5pm, the EV starts even to discharge.
Because the consumption is higher than the production.
And we want to use the ones PV generated energy here.
Yeah, there's also the energy market.
And we could do some price optimization, but no time to explain a strategy here.
But yeah, in general, we can support the grid.
The grid can use the EV.
And for this, we would give some restrictions, a minimal and maximal state of charge.
And then the grid can design, decide when it is, when does it make sense to charge or discharge the EV.
Now, I want to have a look at the entire impact chain of bidder to charging.
I took this diagram from a research project.
We are part of it.
It's quite big.
I made an easier version of for you, but it's important to have in mind.
There are a lot of players in this system that are part of this.
And first, we have a look at this section.
So the communication between the EV and EV's E, which is standby.
E is the O15, 118, E is O15, 118.
And we already heard about it today.
So it defines the procedure of charging session.
And yeah, it provides then tooling for smart charging and also bidirectional charging.
Here we have a quick overview about the features and the different versions of E is O15, 118.
And you can see the dashed 20 version brings the features we need for bidirectional charging.
So smart charging and pause and resume features.
Yeah, then we have another area, the communication between the EV's E and the OCP back.
And so for this, we use OCP to communicate.
And there, again, we have different versions.
And the new one, the 2.1, brings features for smart charging and the support for bidirectional charging.
So also some necessary stuff here.
And then here we have the local consumers and producers of energy.
They can talk with each other via E-bass, for example.
And E-bass also enables the interaction with the grid.
And defines also the behavior of this devices in specific use cases.
And now I want to dive more into errors and show you some internals.
Again, some system architecture.
This one is inside of errors.
So the rectangles are our internals modules.
The ovals are some external service.
And the color purple means that this area is worked in progress.
I want to break it down for you.
On the left we see the communication to the EV.
So here is a 15118.
It doesn't point.
We have the EV's E-Manager.
We have the isomodule.
We have the hardware driver.
In this case, the gate driver.
And the EV.
On the right side, we have OCPP, which also does some authorization.
This is not important right now for us.
But it connects the EV's E-Manager to the OCPP back end.
In the bottom right, we can see the E-E bus related stuff.
This is connected to the energy manager.
And we'll give some limits to charge and discharge.
Yeah, the energy manager, how does it works?
So even one lay down.
It has a representation of the energy tree in it.
So we have, in this case, two EV's E's.
To connect us at one charging station.
They each have a circuit breaker.
And they share also a circuit breaker with 63 AMs in this case.
And if one of these nodes wants to produce or consume more or less energy,
it needs to make a request.
And this root price is brought up to the energy manager.
So following the green arrows.
And then the energy manager asks some logic.
And brings back down through the node and response
with the distribution of the power consumption.
Here, we can see the energy tree in this architecture.
So in the bottom right, the energy manager.
Then there's some limit control by E bus.
Then some limit control by OCPP.
And this is what can be used in the EV's E-Manager.
So now we come to the conclusion.
What are the today's problems?
Yeah, the most EV's and EV's E-V-S-E's.
Don't speak is 15118-20.
So to address this issue, the one thing we do is testing the EV's in the field.
And we have a nice repository with all the lock files.
And with a nice table where you can have a look at which EV has which features.
Then another problem is, okay, an open standard doesn't mean automatically
that we have an open implementation.
This is by ever's targets, exactly this.
And it implements this protocols and standards
or integrate existing ones.
And in some cases like E bus, which comes with a lot of overhead,
it's quite hard to just do a simple implementation by yourself.
So we are all in already on the positive side on the Outlook side.
We have open software.
As I mentioned, Everest, which brings implementation for the, yeah,
is of 15118 stuff and for the OCPP stuff for all the different versions.
So on a good way there, and we have also some other open source projects.
We already heard three of them today.
And yeah, we have, for example, for E bus.
We have a E bus, go library, which we couldn't integrate in Everest.
We have Citroen Res on the OCPP back-and-site, Steve and Maeve.
And we also need hardware to run this open software on.
And there's already hardware that can do this.
There are more than 10,000 chargers in the field,
currently that already run Everest.
And then we have, for example, the Phyres aboard,
which is built in a very modular way.
And I also bring a configuration of it.
It is here in AC configuration, but the board is also designed to do DC
and bi-directional charging.
So, and it can, can run Everest.
So, yeah, it is already available.
Then we have the dashboard, as reference hardware.
It is open hardware, it is already available, designed for AC and DC.
At once Everest.
Then we have the GAT board.
I bought also one, which is more designed to do AC,
but it is also possible to do some DC stuff there.
Also, open hardware, and also already available.
So, there we are on a good way on software and hardware.
We're looking through the future.
And last thing to say is, get involved.
There are multiple open source projects you code country to.
In our case, in Everest, we have open working group calls,
where you can just join ask questions, bring in your ideas,
and yeah, start contributing.
And since there is no much time left,
we can do a Q&A session in the hallway.
Thanks.
We have two minutes to do Q&A here.
Can you talk about the bus as the way to talk building management system?
That's not yours back, right?
That's the else approach call.
Make sure I don't do that, but I do do MQTT.
Yeah.
So, the bus is one way to do it.
So you mean this slide, right?
So the bus is one way.
Yeah, something we are currently on it,
because it's in Germany.
It may be more spreaded to use ebus,
but it's also a bit of clunky,
and it's hard to say,
if it's the best choice to do ebus,
but we will see what the future brings.
Yeah.
Sorry to do what with the battery?
I don't exactly.
So you don't kill the battery by just trying to get older.
Do you want to prevent it from just charging the bus operation?
Do you just keep the problem at the car?
So the ease of 15 and 118,
20 protocol will care about a correct charging and discharging.
But of course, you will have some use of the battery
and the battery will getting worse
with the time as the same,
if you would charge and discharge while driving.
But yeah, this...
The truth.
Yeah.
So thank you for attending.
Time's up.
Thank you.