“fromJSON” Import Path to Reconstruct Circuits/Results from OpenDSSDirect.py JSON

[mohammadrayati]

Summary

OpenDSSDirect.py exposes JSON export utilities (e.g., ToJSON). Is there an official or recommended import path to reconstruct circuits or results from JSON? I

Motivation

Enable fast, reproducible workflows by restoring circuit state/results from persisted JSON without re-parsing DSS files.
Support large-scale studies and scenario generation where re-loading .dss inputs (especially time-series/loadshapes) is costly.
Improve interoperability with data pipelines and programmatic editing of models.

Related

Discussion on JSON schema for ToJSON outputs: JSON schema #128. I couldn’t find a corresponding import/“fromJSON” command in docs or code; please correct me if it exists.

[PMeira]

We have an on-going implementation and some tests on a private branch, including some round-trip tests. I'm working on some unrelated docs, but I'll try to push most of the code this weekend.

The OpenDSS data model is a bit weird. We need to document this better before we start recommending JSON I/O for most users, otherwise they might expect that our JSON schema is just all OpenDSS properties dumped as JSON.

[PMeira]

FromJSON is exposed now in the latest beta releases:

• https://pypi.org/project/dss-python/0.16.0b2/
• https://pypi.org/project/opendssdirect.py/0.10.0b2/
• https://pypi.org/project/altdss/0.3.0b2/

An example ported from DSS-Python:

from opendssdirect import dss as odd
odd.Circuit.FromJSON(r"""{
    "Name": "4busdybal",
    "DefaultBaseFreq": 60.0,
    "PreCommands": [
        "Set EarthModel=Carson",
        "Set VoltageBases=[ 12.470000000000001 4.1600000000000001]"
    ],
    "WireData": [
        {
            "Name": "conductor",
            "RUnits": "mi",
            "RAC": 0.306,
            "GMRUnits": "ft",
            "GMRAC": 0.0244,
            "RadUnits": "in",
            "Radius": 0.3605,
            "NormAmps": 530.0
        },
        {
            "Name": "neutral",
            "RUnits": "mi",
            "RAC": 0.592,
            "GMRUnits": "ft",
            "GMRAC": 0.00814,
            "RadUnits": "in",
            "Radius": 0.2815,
            "NormAmps": 340.0
        }
    ],
    "LineGeometry": [
        {
            "Name": "4wire",
            "NConds": 4,
            "NPhases": 3,
            "Reduce": true,
            "Conductors": [
                "WireData.conductor",
                "WireData.conductor",
                "WireData.conductor",
                "WireData.neutral"
            ],
            "Units": [
                "ft",
                "ft",
                "ft",
                "ft"
            ],
            "X": [
                -4.0,
                -1.5,
                3.0,
                0.0
            ],
            "H": [
                28.0,
                28.0,
                28.0,
                24.0
            ]
        }
    ],
    "Line": [
        {
            "Name": "line1",
            "Geometry": "4wire",
            "Ratings": [
                0.0
            ],
            "NormAmps": 530.0,
            "EmergAmps": 795.0,
            "Length": 2000.0,
            "Units": "ft",
            "Bus1": "sourcebus",
            "Bus2": "n2"
        },
        {
            "Name": "line2",
            "Bus1": "n3",
            "Bus2": "n4",
            "Geometry": "4wire",
            "Ratings": [
                0.0
            ],
            "NormAmps": 530.0,
            "EmergAmps": 795.0,
            "Length": 2500.0,
            "Units": "ft"
        }
    ],
    "Vsource": [
        {
            "Name": "source",
            "Bus1": "sourcebus",
            "BasekV": 12.47,
            "Phases": 3,
            "MVASC3": 200000.0,
            "MVASC1": 200000.0
        }
    ],
    "Load": [
        {
            "Name": "load1",
            "Phases": 3,
            "Bus1": "n4",
            "Conn": "wye",
            "kV": 4.16,
            "kW": 5400.0,
            "PF": 0.9,
            "Model": 1,
            "VMinpu": 0.75
        }
    ],
    "Transformer": [
        {
            "Name": "t1",
            "X12": 6.0,
            "Bus": [
                "n2",
                "n3"
            ],
            "Conn": [
                "delta",
                "wye"
            ],
            "kV": [
                12.47,
                4.16
            ],
            "kVA": [
                6000.0,
                6000.0
            ],
            "pctR": [
                0.5,
                0.5
            ]
        }
    ]
}""", 0)

odd.Solution.Solve()
print(odd.Circuit.AllBusVMag())

Some documentation, including the limitations and what to expect, should be out in a few days, with the full release (non-beta).

[mohammadrayati]

Thank you very much, it's helpful