Reading CGMES Input

cargo build --features cgmes builds src/cgmes.rs, a third network-input path alongside the native JSON format and PGM-JSON, reading CGMES (Common Grid Model Exchange Standard) RDF/XML — the IEC 61970/61968 interchange format ENTSO-E and TSOs use.

It is built on cimoxide — a separate Rust project by the same author — for RDF/XML decoding, via its cimoxide-decoder/cimoxide-structs crates, pulled in under their shorter former names (see Provenance and Licensing). The feature is opt-in since some users only need JSON input and shouldn't pay for cimdecoder's dependency tree or build time.

#![allow(unused)]
fn main() {
use gridoxide::cgmes::{load_profiles, cgmes_to_buses_and_branches};
use gridoxide::network::{build_ybus, stamp_shunts};
use gridoxide::run_power_flow_analysis_from_ybus;

let ds = load_profiles(&[&eq_path, &ssh_path, &tp_path, &sv_path])?;
let (buses, lines, transformers, shunts) = cgmes_to_buses_and_branches(&ds, 100e6)?;
let mut ybus = build_ybus(buses.len(), &lines, &transformers);
stamp_shunts(&mut ybus, &shunts);
let result = run_power_flow_analysis_from_ybus(buses, ybus);
}

What the importer expects

The standard EQ+SSH+TP+SV "solved case" profile bundle:

• TP is required. TopologicalNode is used directly as gridoxide's Bus, so switch-state topology processing is assumed already resolved upstream. See Ideal Switches and Zero-Impedance Branches for what that resolution involves and how cgmes::merge_closed_switches handles the node-breaker case.
• SV must carry a populated TopologicalIsland.AngleRefTopologicalNode, used as the slack bus. See Multi-Island Power Flow for how reference buses are picked per island.

What is mapped

Loads — EnergyConsumer, ConformLoad, NonConformLoad, EquivalentInjection, ExternalNetworkInjection, and AsynchronousMachine. The last is converted like a plain load, with both P and Q negated.

Branches — ACLineSegment and SeriesCompensator, including ACLineSegment.gch, real shunt conductance, not just bch's reactive charging.

Transformers — 2- and 3-winding PowerTransformers, with RatioTapChanger (including its optional RatioTapChangerTable per-step override, falling back to the linear stepVoltageIncrement formula when absent) and all four PhaseTapChanger variants: Linear, Symmetrical, Asymmetrical, and Tabular.

Shunts — LinearShuntCompensator and NonlinearShuntCompensator.

Voltage-controlled buses — SynchronousMachine plus RegulatingControl, and the same mechanism for StaticVarCompensator and ExternalNetworkInjection, minus the active-power term for the former.

Validation

Validated end-to-end against four ENTSO-E conformance cases, with fixtures referenced via a git submodule (see tests/data/cgmes/README.md):

MicroGrid-BE-MAS and MiniGrid converge cleanly but match their own published SV voltages only within a few percent. That gap was cross-checked (for MicroGrid-BE-MAS) against pypowsybl's own independent CGMES import and AC load flow on the same case, which shows a comparable deviation from the same published values (scripts/bench/cross_validate_cgmes_microgrid_be.py) — confirming it is inherent to solving a boundary-truncated area file with fixed-injection equivalents, not a correctness bug. One known, documented limitation contributes: types::Line has no tap ratio, so it can't absorb the small nominal-voltage mismatch CGMES explicitly allows at boundary tie points.

Not built or tested in CI — the same local/manual-verification posture as klu and pardiso.

The per-class pages

The remaining pages in this section each take one CIM class or attribute that needed real modeling work, and follow the same structure: why it matters, the concepts and formulas involved, where it sits in gridoxide today, and how other tools handle it.