branch.csv

This file defines branches - flow pathways between pairs of buses - including lines and transformers. Add a row for each branch in the system. Each row in the CSV file will cause a branch dictionary to be added to ['elements']['branch'] in the Egret model.

ListTable

Column Name	Description	Egret
UID	A unique string identifier for the branch.	Used as the branch name in Egret. Data for this branch is stored in a branch dictionary stored at ['elements']['branch'][<UID>].
From Bus	The Bus ID of one end of the branch	The Bus Name of the bus with the corresponding Bus ID, as entered in bus.csv, is stored in the Egret branch dictionary as from_bus.
To Bus	The Bus ID of the other end of the branch	The Bus Name of the bus with the corresponding Bus ID, as entered in bus.csv, is stored in the Egret branch dictionary as to_bus.
R	Branch resistance p.u.	Stored in Egret bus dictionary as resistance.
X	Branch reactance p.u.	Stored in the Egret bus dictionary as reactance.
B	Charging susceptance p.u.	Stored in the Egret bus dictionary as charging_susceptance.
Cont Rating	Continuous flow limit in MW	Stored in the Egret bus dictionary as rating_long_term. Optional.
LTE Rating	Non-continuous long term flow limit in MW	Stored in the Egret bus dictionary as rating_short_term. Optional.
STE Rating	Short term flow limit in MW	Stored in the Egret bus dictionary as rating_emergency. Optional.
Tr Ratio	Transformer winding ratio.	If non-zero, branch is treated as a transformer. If blank or zero, branch is considered a line. See Lines and Transformers below.

Additional Branch Values

The following values are automatically added to every branch dictionary in the Egret model:

• in_service = true

• angle_diff_min = -90

• angle_diff_max = 90

• pf = null

• qf = null

• pt = null

• qt = null

Lines and Transformers

Each branch is either a line or a transformer. The type of branch is determined by the Tr Ratio. If this field is blank or zero, the branch is a line and the following property is added to the branch dictionary:

• branch_type = line

If the Tr Ratio is a non-zero value, the following properties are added to the branch dictionary:

• branch_type = transformer

• transformer_tap_ratio = Tr Ratio

• transformer_phase_shift = 0