... controlling an electric car charger to charge from solar energy as efficient as possible.
For the deployment on a k8s cluster and the used hardware, see the related project pv-monitoring.
pv-control contains:
- A control loop implemented in Python that reads energy data from the inverter and sets the charge current of the wallbox.
- Some logic to control 1-phase vs 3-phase charging of the go-e wallbox via an external relay. Therefore, pv-control must run on a Raspberry PI.
- A we-connect client to read the SOC for an VW ID3.
- A number of REST endpoints to control the operation like setting charge mode and to get basic info about energy consumption.
- A simple UI implemented in Angular optimized for mobile phones.
- A Prometheus endpoint for monitoring the charging process.
PV-Control implements the following charge modes/strategies:
- OFF
- PV only - Try to charge with solar power only.
- PV all - Try to charge all available solar power into the car.
- Max - Charge with full power, i.e. 11 kW (3x 16A).
- Manual - Wallbox is manually controlled e.g. by the go-e app.
'PV only' and 'PV all' use different strategies when working around the limitations of the wallbox and electric car, i.e. the minimal charging current of 6A and the charging current steps of 1A.
Automatic phase switching between 1 and 3 phases for the PV modes is implemented but not yet tested in practice because my 7 kW peak solar power system gives little opportunity of 3 phase charging. Currently, the 'Auto' mode selects 1-phase charging for 'PV only' and 'PV all' and 3-phase charging for 'Max'.
A relay allows to switch between 1 phase and 3 phase charging. The control loop ensures that phase switching happens only when the wallbox is not charging. After switching, the go-e wallbox needs a reset.
Restarting pv-control (e.g. for updates) doesn't change the state of the relay. A reboot of the Raspberry initializes the relay to 1-phase charging.
python -m pvcontrol --help
usage: __main__.py [-h] [-m METER] [-w WALLBOX] [-r RELAY] [-a CAR] [-c CONFIG] [--hostname HOSTNAME] [--host HOST] [--port PORT] [--basehref BASEHREF]
PV Control
optional arguments:
-h, --help show this help message and exit
-m METER, --meter METER
-w WALLBOX, --wallbox WALLBOX
-r RELAY, --relay RELAY
-a CAR, --car CAR
-c CONFIG, --config CONFIG
--hostname HOSTNAME server hostname, can be used to enable/disable phase relay on k8s
--host HOST server host (default: 0.0.0.0)
--port PORT server port (default: 8080)
--basehref BASEHREF URL prefix to match ng base-href param (no leading /)
METER, WALLBOX and CAR refer to implementation classes for the energy meter, the wallbox and the car:
- METER = KostalMeter|FroniusMeter|SimulatedMeter
- WALLBOX = GoeWallbox|SimulatedWallbox|SimulatedWallboxWithRelay
- RELAY = RaspiPhaseRelay|SimulatedPhaseRelay
- CAR = VolkswagenIDCar|SimulatedCar|NoCar
CONFIG is a json with 'meter', 'wallbox', 'relay', 'car' and 'controller' configuration structures. The config parameters depend on the METER, WALLBOX, RELAY and CAR type. See the corresponding ...Config data classes
in the source files meter.py, wallbox.py, car.py and chargecontroller.py.
HOST, PORT and BASEHREF configure the web server. BASEHREF can be used to add a prefix to the web server url so that it matches ng build --base-href BASEHREF/ if not running behind an ingres on k8s.
HOSTNAME should be set to the host or node name where pvcontrol is running (e.g. by k8s metadata). Allows to automatically disable the phase relay when not deployed on correct hardware, i.e. pv-control still works but with reduced functionality.
Pre-requisites:
- Raspberry Pi 2 with Raspberry Pi OS Lite (Debian 12), or newer model
- Raspberry Pi Expansion Board, Power Relay
- Python 3.13
- installation like described in (https://wiki.lupsha.com/how-to-upgrade-to-python-3-12-on-raspberry-pi/)
- needs a venv on Debias 12 for pip
- download
pv-control.tar.gzpackage (release artifacts or from github actions)
The following procedure installs pvcontrol behind an nginx on port 80.
python -m venv --system-site-packages ~/.env
source ~/.env/bin/activate
sudo mkdir -p /usr/local/bin/pvcontrol
sudo tar -xzf pv-control.tar.gz -C /usr/local/bin/pvcontrol
cd /usr/bin/pvcontrol
pip install -r requirements.txt
sudo cp /usr/local/bin/pvcontrol/pvcontrol.service /etc/systemd/system
# adapt configuration in /etc/systemd/system/pvcontrol.service
sudo systemctl daemon-reload
sudo systemctl start pvcontrol.service
sudo systemctl enable pvcontrol.service
sudo apt install nginx
sudo cp /usr/local/bin/pvcontrol/pvcontrol.nginx /etc/nginx/sites-available/pvcontrol.nginx
# adapt pvcontrol.nginx if needed (e.g. multiple apps running on same raspi)
sudo ln -s /etc/nginx/sites-available/pvcontrol.nginx /etc/nginx/sites-enabled/pvcontrol.nginx
sudo rm /etc/nginx/sites-enabled/default
sudo systemctl start nginx
# journalctl -u pvcontrol.service -f
# http://pvcontrol.fritz.box
pvcontrol can be updated using the update-pvcontrol.sh script. Prerequisites:
- gh cli installed as described in https://github.com/cli/cli/blob/trunk/docs/install_linux.md
- successful github login, e.g. with
gh auth login -w - pvcontrol was installed as described above
update-pvcontrol.shscript copied into home directory of raspberry- Usage
./update-pvcontrol.sh- update to latest successful build result of main branch./update-pvcontrol.sh <version>- update to specified version (github release tag, e.g. v4)
Tested on Raspberry Pi 4 with Raspberry Pi OS Lite (Debian 12, 64 bit).
Example k8s manifest for deploying pv-control:
pv-control contains a number of mock implementations for wallbox and inverter/power meter to allow testing and local development.
Basic setup:
- Python 3.13 (use pyenv and create a virtual env pv-control-3.13)
- a recent version of node and npm (see Angular requirements)
How to run locally:
# in pv-control/ui
npm install
ng build
# in pv-control
pyenv activate pv-control-3.13
pip install -r requirements.txt
python -m pvcontrol
# http://localhost:8080
How to run Python tests:
pip install -r requirements-dev.txt
python -m flake8
pyright
python -m unittest discover -s ./tests
How to run UI tests:
# in pv-control/ui
ng lint
npm run test
For reproducible builds, requirements.txt shall pin all packages using pip-compile. Update Python deps:
# pyenv activate pv-control-3.13
python -m pip install --upgrade pip
pip install -r requirements-dev.txt -U
pip-compile --upgrade --resolver backtracking --allow-unsafe requirements.in
# edit requirements.txt and add/edit platform specific dependencies: RPi.GPIO
pip install -r requirements.txt -U
A docker container ghcr.io/stephanme/pv-control is built for every commit via github actions. The arm image is intended to run on a k8s cluster on a Raspberry node.