Parameter Initialization

Parameter Initialization and Time Scale Interoperability

This guide is intended as an informal place to discuss, document, and share how to represent and transform power system models over varying time scales.

Power Flow $\rightarrow$ Phasor Dynamics

Load & Shunt Models

Near nominal voltage magnitude and frequency are often modeled as constant impedances at the terminating bus.

Transformer Models

Information on phase and tap controls

QV Limits

Phasor Dynamics $\rightarrow$ EMT

Effective EMT modeling requires some a priori engineering judgment based on the temporal & spatial scale of the problem.

Frequency Dependence

Often approximated, especially when empirical data are missing.

Propagation Delay

The delay in TEM propagation can be approximated algebraically for short transmission lines or at low frequencies.