Timedata InfluxDB Question

English Forum Software-Development
1

Hello!

I am pretty new to openEMS, but I think it is a great project.
I have programmed a controller and I am trying out different scenarios to see how it reacts. Currently I am trying to simulate a week. In order to do this, without letting the program run for a whole week, I set the core cycle at 50 ms and the number of cycles after which the Timedata InfluxDB writes the information to a InfluxDB database to 1. However the data is written in the database once every second, not 20 times a second as I wanted.
Does anyone know how to fix this this?
Is it at all possible for the Timedata InfluxDB to write the data so often in a database?
If it isn’t possible, is there another way to simulate a week in a couple of hours?

Best regards,
Vincenzo

2

Hi Vincenzo,

welcome to the Community.

By default the writes to InfluxDB are truncated to one value per second. You should be able to adjust implementation for your use-case here:

Apart from that: I am working on a “Simulator” which might be exactly what you need. It is already functional, but unfortunately still lacks proper documentation and a nice UI.

To try if it suits you, you would have to

  • Activate the “Controller Api REST/JSON Read-Write” in OpenEMS. (I usually use the Talend API Tester chrome extension)
  • Then send a executeSimulation JSONRPC-Request (see the example here), that defines the simulated Components, simulated data and simulation parameters.
    • components keeps the configuration for each Component, just like Apache Felix Configuration Admin would do
    • clock defines the duration of the simulation.
      • To simulate a real-time execution set the timeleapPerCycle to 1000 (i.e. 1 second) and executeCycleTwice to false.
      • (The settings in the example (timeleapPerCycle:900000, executeCycleTwice:true) are for a simulation of 15 minutes values, e.g. for industrial peak-shaving applications)
    • profiles: define the input data. This is the data you currently provide via a datasource.
    • collect: defines the channels that you would want to record.
  • The simulation will then run for a while… watch the logs to see the progress
  • Once it’s finished it returns a JSONRPC-Response, that holds the collected channel data as a JSON
  • The Simulator-App also behaves like a Timedata service in OpenEMS, so you can also see the simulated results in OpenEMS UI.

Looking forward to hearing from you about this. I am curious to know if it works for you.

Regards,
Stefan

3

Hi Stefan!
Thanks for the quick reply!
I have tried to change that row, but it doesn’t really work. The data is still being written once per second. Maybe I’ve done it wrong. Could you be a little more specific about how I should change it?

4

I have not tried it, but this should work:

	protected synchronized void collectAndWriteChannelValues() {
		if (++this.cycleCount >= this.config.noOfCycles()) {
			this.cycleCount = 0;
			final Builder point = Point.measurement(InfluxConnector.MEASUREMENT).time(System.currentTimeMillis(), TimeUnit.MILLISECONDS);
			final AtomicBoolean addedAtLeastOneChannelValue = new AtomicBoolean(false);
			[...]
5

Thanks a lot, it worked!

That is actually exactly what I have tried, but because the Influx DB log was shown once per second, I falsely assumed that the data is also truncated once per second. After I quarried the data I was able to see that it was logged much more than once per second.

Many thanks and keep up the good work!

6

hello, Vincenzo.B
what did u do to achieve this?