Quattro & BYD V2L - Grid Feed-in Problem

Q&A and troubleshooting EVCS
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1

Hi.

I finally managed to use my BYD V2L output to use as Generator :slight_smile:

I used the recommended configuration:
AC1 Is set to Generator (current limit is set to 16A)
AC2 is set to Grid (current limit is set to 20A = Grid circuit Breaker rating)

I did not want to manually change the cables for charging and discharging mode.
So I added a small circuit and made my own cable, to use the same cable for charging and discharging the vehicle.
You can NOT use the supplied charger cable for discharging!

I can now switch between charging and discharging via homeassistant :slight_smile: or a manual push button at the box.
Have a look at the circuit diagram using just 2 relais, a push button and a shelly 1 Mini Gen4, pretty simple
V2L.pdf (39.7 KB)

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I had some problems in the beginning, where the car inverter tripped.
Reason:
the output of the cars inverter was possibly overloading,
because the Quattro was trying to charge my Solar battery from the generator on AC1-IN !
…and of cause this was by far to much for the poor cars inverter.

After some research, I found a solution for that.
There is a Assistant called “charge current control” :slight_smile:
Which I configured as follows:

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…but the cars inverter still kept tripping … damn :thinking:
It turns out that I had to disconnect the Earth wire (PE) from the car to the Quattro!

After that, the car was finally delivering power, without tripping :slight_smile:
But still sometimes it did not go into discharge mode :frowning:

The reason for that, was the cars logic.
One has to connect the load within 30 seconds after the V2L was enabled (shows on the cars dashboard)
If not connected within 30 seconds,
one has to UNLOCK the car to start V2L
(which was described in the cars manual but who reads that? right? :face_with_peeking_eye: )

Problem:
I thought when the genset is used, it would still honor dynamic ESS and use my solar battery as well.
Meaning it would still prioritize the solar battery, down to the target SoC (ass set by Dynamic ESS)
But that does not seem to be the case
The Inverter is not using my solar battery, when the Quattros “active AC input” = AC input 1 :frowning:
What did I miss here? Can that be changed?

The bigger problem is,
the grid feed-in does not work anymore

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The Solar chargers MppOperationMode is toggling between “1=Voltage/current limited” and “2=MPPT active” every 3-4 seconds

The Grid feed-In worked flawlessly the last couple of years!
I checked through what ever I could think off, but at the moment I run out of ideas :frowning:

So if anyone has an idea or solution, which settings I need to check or change, please let me know

Thanks in advance
Jurgen

2

Preface- if acin 1 is connected ac2 is ignored.
So it will prioritise the ac1 if it is acive. While this is not related to your feedback issue. I just thought to mention it.
Most people when they have connected a generator it is because the battery will be charged up, not usually to power assist like a grid. So maybe labelled as generator that is an issue, try label it as grid.

What is unclear here in your question:-

Are you trying to feedback to the grid itself on ac2 when the vehicle on ac1 to charge it?

Are you actually using dynamic ess (DESS) or just ESS assistant with the base or usual discharge to a certain level type thing? (Again dess would not apply to a geneset connection as that is not a dynamic price and when a person runs a generator it is run as little as possible)

Other solution may be to just switch the ac inputs over and label them both grid.

3

Thanks for your reply :slight_smile:

Quote:
”Preface- if acin 1 is connected ac2 is ignored.”
That is exactly what I wanted!

The cars inverter (V2L) should NEVER charge the Solar Battery!
This is why I installed the Assistant called “charge current control”
This is working as intended :slight_smile:
…and marking it AC1-In as GRID, might try to “feed-in” the cars inverter - which I believe will damage the cars inverter.

The default is, connecting the car to the EV-Charger and AC2-In becomes the active AC input!
In this mode, the car does NOT supply the AC1-IN

What is NOT working anymore, is “Grid Feed-In”, in my case to AC2-IN :frowning: …and I can not figure out why.
The system is setup with an ESS assistant and Dynamic ESS is enabled in “Green Mode
( the Solar battery was discharged at night accordingly)

This has worked for years without a problem and has worked until yesterday morning at around 10 o’çlock.

Since then, I found that:
The Solar chargers MppOperationMode are toggling between “1=Voltage/current limited” and “2=MPPT active” every 10-15 seconds.
The 5 Minutes grafic shows charger output Power SoC and Grid Power

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Effectively stopping grid feed-in to AC2-In :frowning:

4

Ok. Good to know that not what you werr trying to do.

Does the solar completely stop producing when the ‘generator’ is connected?

When making changes did you run any updates?

5

I don’t know. The car is currently charging and NOT connected as Generator.
I will only switch to V2L, when the car is fully charged that might be in an hour or so :slight_smile:

I was running on the latest Beta version v3.80~13 when this happened.
I reverted back to the official VenusOS V3.72.
But that did NOT change anything

6

the issue that the

Solar chargers MppOperationMode are toggling between “1=Voltage/current limited” and “2=MPPT active” every 10-15

does not go away :frowning:

I disconnected the car after being fully charged - still the same.

I then additionally disconnected the grid on AC2-In - still the same :frowning:

I then switched V2L mode ON:

The car started V2L and AC1-In generator is active and the solar charger MPPOperationMode switches to “0” and stops charging completely

…any ideas?

7

Get a micro usb and do a fresh install on the gx. Sometimes a roll back still leaves a mess in the OS.

Additionally i have found using dess anless you have dynamic pricing not very helpful and it is easier to set up scheduled charge or a custom node red flow for things.

Are you running any software mods? Often it is also something there that is causing a conflict in logic

8

Good morning
I will try to do the fresh install via Micro USB.

Do I use VenusOS from here?
https://github.com/victronenergy/venus/tags ?

can the tar.gz images be used directly?

Do I need to backup the current settings?

9

No software mods

10

Dynamic ESS works fine for me.

It uses the batteries as intended when AC2-In (Grid) is selected.
Like this morning when I disconnected the Vehicle from the AC1-IN
Discharging the batteries to whatever Dynamic ESS sets the Target SoC

My biggest problem is the “Excess Solar” not being feed-in into the Grid :frowning:

11

I guess I found the right location for the GX firmware files at:

using any of the
“venus-install-sdcard-cerbogx-**************.img.zip files
or
”venus-swu-cerbogx-**********.swu” files

???

12

Yes. The version for the cerbo specifically Einstein. And then what every version was stable for you.

13

I have downloaded
“venus-install-sdcard-einstein-**************.img.zip”
and
”venus-swu-einstein-********.SWU”
files
and copied them to a sd-card (fat32)

When ”Check for updates on SD/USB”
I get “No firmware found” :thinking: **
**
What did I miss here?**
**

14

There is a reset to default option above the link.