FAQ

This is a list of some questions we recently got. If you cannot find an answer for your questions here, you are welcome to post it on our mailing list.

General questions

Are there graphical tools for scenario design?

Maverig, an environment for graphical analysis as well as scenario design has been developed and is currently in a prototypical state. It may be used for demonstration purposes, but its maintenance and further development is not our top priority right now. Please understand, if the installation guide is not up-to-date with the newest package versions. However, we argue that graphical tools are not feasible for the design of large and complex scenarios. For most applications the more flexible scenario design by code is advantageous.

Is there a mosaik-Wiki?

We like Wikis but consider them the wrong tool for documenting software (and we are not alone with that).

There are a lot of other resources, though:

  • All documentation is concentrated here, at Read the Docs.

  • Source code and issues are managed by GitLab.

  • Discussion takes place in our mailing list.

  • News are spread through our blog.

There’s not much that a wiki could add here.

Coupling models with mosaik

Can I use continuous models with mosaik?

Yes. Since mosaik 2 you can even use a variable step size for your simulator that can dynamically change during the simulation.

Can I use mosaik only with Python programs?

No, mosaik can be used with any language that provides network sockets and ways to (de)serialize JSON.

Since implementing network event loops and message (de)serialization is repetitive work and unnecessary overhead, we provide so called high-level APIs for certain languages that provide a base class that you can inherit and just need to implement a few methods representing the API calls.

Currently, high-level API are available for Python, JAVA, and C#, but an implementation for C++ will follow soon.

The mosaik demo

I can only see active power values in the web visualization. Does mosaik also support reactive power values with PyPower?

Of course, it only depends on your models. The basic models distributed with mosaik 2 only produce active power outputs (cos phi = 1), so we don’t display reactive power.

What are the power grid’s parameters? How are the cables’/lines’ parameters formatted?

Check https://gitlab.com/mosaik/mosaik-pypower under “input file format”. Typically, line values are given in R per km and X per km.

Port 8000 on my local machine is already in use. How can I see the visualisation with WebVis?

Port 8000 is used as default when using WebVis. You can overwrite the default value in demo.py.

...
sim_config = {
    ...
    'WebVis': {
        'cmd': 'mosaik-web -s 0.0.0.0:8000 %(addr)s',
    },
}
...