Model validation¶
power-grid-model is validated using multiple cases present in tests/data folder. There are 2 simple grid test case examples of power-grid-model validated vision and gaia. A thorough validation is done using minimal test cases of each component and 2 test networks described in the following sections.
Minimal test cases in pandapower¶
Their results are validated against the pandapower library.
The cases of a differences in modelling between both the libraries are handled by theoretical workarounds. For example in power-grid-model, source impedance is included for all component sequences. In pandapower, source impedance is present only in positive sequence network whereas it considered in all sequence components in power-grid-model. Source impedance is then set to a low value to match this modelling difference. Hence, the result of source component here should be ignored. The output result attributes of power-grid-model are validated at a tolerance value of \(\pm10^{-5}\) of respective unit. Both the iterative algorithms: Newton Raphson and Iterative current are validated.
All the test cases can be found in /tests/data/power_flow/pandapower.
Node¶
A node can have 2 states: energized and non-energized which is presented in the first grid. The second grid example uses a line to validate node operation for voltages other than 0 or 1 p.u. The circuit diagram for test cases of the 2 grids is as follows:
Line¶
A line can be 4 states, closed on both ends, open on both ends and open on any one end. The circuit diagram for the test case is as follows:
Transformer¶
A transformer can be 4 states, closed on both ends, open on both ends and open on any one end. The tap changing functionality is tested using a batch calculation for various tap positions.
Note
Asymmetrical calculations are possible only for grounded network transformer in pandapower. Hence open cases are not evaluated.
Relaxed tolerance parameters are used in asymmetric calculation because only ‘T’ transformer model is available in pandapower while power-grid-model uses ‘pi’ model.
Shunt¶
A shunt can be in 2 states: open or closed.
Source¶
While source is present in all cases, this case tests two sources being used together.
Symmetrical Load¶
A symmetrical load can be in open or closed state. It can be of 3 types: constant power, constant impedance and constant current.
Symmetrical generator¶
A symmetrical generator can be in open or closed state. It can be of 3 types: constant power, constant impedance and constant current.
Note
Only constant power implementation is possible in pandapower for asymmetrical calculations. All the Z, I and P loads are already validated for symmetrical calculation.
Asymmetrical load¶
An asymmetrical load can be in open or closed state.
Component Test Case: Asymmetrical generator¶
An asymmetrical generator can be in open or closed state.
Test case creation¶
Contribution to power-grid-model is also possible by creating own test cases in similar format. A guide for exporting the input or output data is given in Make Test Dataset.