power-systems-modeling

name	power-systems-modeling
description	Covers thermal rating models (CIGRE TB 601, IEEE 738), conductor physics, and electrical properties for overhead transmission lines. Use when implementing thermal calculations, validating conductors, or computing sag and resistance. Not for infrastructure deployment (use infrastructure-management) or system architecture.

Power Systems Reference

Contents

• Critical Rules
• Verification
• Quick Reference
• Topics
• Available Scripts
• Default Standard
• Unit Conventions
• Standard Citations
• Testing Tolerances
• Related Skills

Follows foundations code quality and TDD principles.

Domain knowledge for overhead transmission line physics, thermal ratings, and mechanical analysis.

Critical Rules

• Always validate physical parameters at function boundaries; raise ValueError for out-of-range values
• Use CIGRE TB 601 as the default thermal rating standard; document deviations in code comments
• Always cite standard section numbers in code comments (e.g., CIGRE TB 601, Section 4.2.3)
• Use SI units internally (temperatures in Kelvin); convert to Celsius only for display
• Use pytest.approx() with rel=1e-3 for thermal calculation tolerances

Verification

• Confirm all physical parameters are validated against bounds before computation
• Verify standard citations are present in code comments for thermal formulas
• Run scripts/validate-bounds.py to check parameter values against physical limits

Quick Reference

Parameter	Valid Range
Conductor temperature	-40°C to 250°C
Ambient temperature	-50°C to 60°C
Wind speed	0 to 50 m/s
Solar radiation	0 to 1400 W/m²

Topics

Topic	Reference	Use When
Thermal Models	references/thermal-models.md	CIGRE TB 601, IEEE 738 thermal rating implementations
Conductor Limits	references/conductor-limits.md	Physical validation bounds and parameter constraints
Electrical Properties	references/electrical-properties.md	Resistance, sag, catenary formulas and calculations
Standards Reference	references/standards-reference.md	Industry standards summary (CIGRE, IEEE, IEC, EN)

Available Scripts

Script	Usage	Description
scripts/validate-bounds.py	validate-bounds.py -t conductor_temp -v 85	Validate physics values against bounds
scripts/convert-units.py	convert-units.py 25 C K	Convert between units (temp, length, power, speed)
scripts/check-standard-refs.sh	check-standard-refs.sh <dir>	Check for proper CIGRE/IEEE citations in code

Default Standard

CIGRE TB 601 is the default thermal rating standard. Document any deviations in code comments. IEEE 738 differs in treatment of low wind speeds.

Unit Conventions

• Internal: SI units, temperatures in Kelvin
• Display: Celsius for temperatures
• Document: Always include units in variable names or docstrings

Standard Citations

Always cite standard section numbers in code comments:

# CIGRE TB 601, Section 4.2.3: Natural convection heat loss
# Formula: P_n = pi * D * lambda * Nu * (T_s - T_a)

Testing Tolerances

Thermal calculations: use pytest.approx() with rel=1e-3 (0.1% accuracy).

Related Skills

• database-design — For persisting physics results
• foundations/code-style — For Python conventions in physics code