PVControl

GUI Controller for PVOptimize

Introduction

The project PVOptimize allows to flexibly manage how a PV rooftop installation charges an EV. However, the only way to make use of the flexibility is through a config.ini file.

This project provides a GUI to control relevant aspects from a Node-RED Dashboard. This GUI is an optional addition to PVOptimize. Some familiarity with Node-RED might be needed to install.

Improvements are welcome - please use Issues and Discussions in Git.

---

Table of Content

• Introduction
• Architecture
  • Enabling the GUI
  • Bootstrapping the Loop
• Usage of the GUI
• Installation
• Version History
• Disclaimer
• License

Table of contents generated with markdown-toc

---

Architecture

The following depicts the basic architecture:

• PVOptimize is called every minute or so from eg. an appropriate crontab entry
• it returns a pvstatus.json file with three sections ctrlstatus (controller status), pvstatus (PV system status) and wbstatus (wallbox status). (An additional member pvcontrol is used to report current settings to the GUI, in case the GUI is re-started)
• this contains sufficient information to initally configure the dashboard (slider lengths, default values, wallbox status to be displayed in rightmost State group)
• upon Save of the dashboard settings, a gui_config.ini is created, which contains PVControl items
• on next call of PVOptimize, (1) the default config file config.ini is read, then (2) the gui_config.ini which overwrites values of config.ini and thus makes PVOptimize behave as configured in the dash board

The dashboard flow is basically generic to PVOptimize in version 2.0, except for a section marked as Hardy Barth specific (for the State group)

Enabling the GUI

• The GUI is enabled in config.ini by setting PVControl.enableGUI = 1.
• The files pvstatus.json and gui_config.ini are located in the directory PVControl.guiPath, which defauts to ~/.node-red/projects/PVControl

Bootstrapping the Loop

Since the above picture shows a loop, it is essential to understand how it is inialized:

• as soon as PVControl.enableGUI = 1 is set, PVOptimize starts reading gui_control.ini and its values will overwrite corresponding values in config.ini in section PVControl.
• config.ini contains default values for slider ranges in the GUI:
  • HardyBarth.I_chargeMin and HardyBarth.I_chargeMax determine minimum and maximum of sliders in group Charge Control
  • PVStorage.minSOC determines the lower end of the SOC sliders in group SOC Control
• once PVOptimize runs (ie., every minute), these values are written into pvstatus.json
• the Node-RED flow uses these values when deployed to setup the dashboard - hence if changes are needed, a re-deployment (flow re-start) is required
• once Save is pressed in the GUI, a new gui_control.ini is created, which is read by next call to PVOptimize.
• Note that after every dashboard re-deployment (flow re-start), values will initialize as shown below, independent of actual values in gui_contro.ini. Hence, one wants to save values immediatly, to gain consistency between display and behind-the-scenes activities.

To bootstrap the flow, default files for pvstatus.json and gui_config.ini are provided, but they may not fit every situation.

Usage of the GUI

The GUI dashboard is called with <ip_of_host_running_GUI>:1880/ui from any browser and should bring up a panel similar to below:

It consists of three groups:

• Charge Control and SOC Control control the config items as described in PVOptimize documentation
• State displays the current state of the wall box and a one-hour history of requested charge current

Charge Control contains two additional widgets, not described so far:

• Delayed charging delays charging to the time Charge Start (further subject of other constraints of PVOptimize)
• Charge Start sets a starting time for enabling charging. For this to work, Start NOW obviously needs be disabled. Once the time is reached, Start NOW is enabled - in other words, Charge Start expires after latest 24 hours.

Installation

The project requires Node-RED on the same host as PVOptimize is installed. It has been developped and seen running with the following versions and components:

Software	Version
Node-RED	v 2.1.4
node.js	16.13.1 (or 17.3.0)
node-red-dashboard	3.1.3
node-red-contrib-projectdir	2.0.5

Ensure that Node-RED is restarted at boot time as described here, using pm2

Node-RED has to be setup to handle projects and the project files reside in ~/node-red/projects/PVControl. This directory is also used to exchange information with PVOptimize as described above. Ensure that this project is deployed.

Once the flow is installed (and a manual trial run successfully executed), enable PVControl.enableGUI = 1 in config.ini of PVOptimize.

Version History

Version	Date	Comment
1.0	January 2022	Initial release
1.1	2022-07-03	minor bug-fixes, Start Now switch replaced with Delayed Charging

Disclaimer

The software controls PVOptimize. Errors in the GUI software can result in PVOptimize not to perform its desired task - as an example, the EV could remain un-charged in the morning. The author cannot be held liable for this or any other damage caused through the use of this software.

Use at your own risk!

Further warranty limitations are implied by the license. Note that PVOptimize contains a similar disclaimer.

License

Distributed under the terms of the GNU General Public License v3.