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qfmu is a python package to generate continuous-time, LTI system FMUs from command line.

Installation

Install qfmu through PyPI

pip install qfmu

Noted that a C compiler is required

• msvc for Windows
• gcc for Linux
• clang for MacOS

Features

Currently, qfmu is able to generate fmus that are compliant with FMI2 standard.

The following models are supported:

Model	ME	CS
State Space (ss)	✔️	✔️
Transfer Function (tf)	✔️	✔️
ZeroPoleGain (zpk)	✔️	✔️
PID (pid)	✔️	✔️

Noted that only continuous-time models are supported currently.

Examples

Generate a continuous-time state space FMU

qfmu ss -A "[[1,2],[3,4]]" -B "[[1],[2]]" -C "[[1,0],[0,1]]" -x0 "[3.14, 6]" -o ./example_ss.fmu

If qfmu is installed properly, you should see a example_ss.fmu file generated in your current working directory.

If you have fmpy installed, you can run fmpy info example_ss.fmu to see detailed model information.

Model Info

  FMI Version        2.0
  FMI Type           Model Exchange, Co-Simulation
  Model Name         q
  Description        None
  Platforms          c-code, linux64
  Continuous States  2
  Event Indicators   0
  Variables          10
  Generation Tool    qfmu
  Generation Date    2023-10-08 21:24:32.733857

Default Experiment

  Stop Time          1.0
  Tolerance          0.0001

Variables (input, output)

  Name               Causality              Start Value  Unit     Description
  u1                 input                          0.0           Model input 1
  y1                 output                                       Model output 1
  y2                 output                                       Model output 2

Generate a continuous-time transfer function FMU using the numerator, denominator representation: $\frac{s}{s+1}$

qfmu tf --num "[1]" --den "[1,1]" -o ./example_tf.fmu

Generate a continuous-time transfer function FMU using the zero-pole-gain representation: $\frac{0.5(s-1)}{(s+1)(s+2)}$

qfmu zpk -z "[1]" -p "[-1, -2]" -k 0.5 -o ./example_zpk.fmu

Generate a continuous-time PI controller FMU: $3 + \frac{0.1}{s}$

qfmu pid --kp=3.0 --ki=0.1 -o ./example_pid.fmu