In order to simplify the text, the PI line sections are called PI lines in this Chapter.

Introduction

The PI line model is mainly used for short transmission lines. See equivalent diagram on Figure
7 - 29.

PI Section Equivalent Diagram

PI Line Icon and Diagram

Parameter Description

General Parameters

Base MVA	Base power in MVA
Base Volt	Line base voltage - phase to ground kV
Base Freq	Base frequency (Hz)
Length	Line length (km)
Database key name	Key to access the line data base (optional package).

EMTP Geometric parameters

Fault/file

to reset values / calculation of parameters

File name

EMTP or Inpurdue format file containing the geometric parameters of the lines.

The EMTP “.pun” format is not allowed with this model.

RLC Parameters--Matrix/Sequences

Matrix (untransposed line	fill in the matrices
Sequences (transposed line	fill in the sequences
R, L, C	R, L, C matrices (ohm/km, henry/km, farad/km)
Sequence 0	Zero sequence
Sequence 1	Positive sequence

Fault Parameters

The fault parameters are exactly the same as those for constant parameters lines. For more details,
see 3– on page 144.

List of Available Signals

At acquisition, the following signals are made available by the sensors:

Line Signals

I1(a,b,c)_bus label	Current in each phase at end 1
I2(a,b,c)_bus label	Current in each phase at end 2

Fault Signals

V(a, b, c)_FLT_line label	Voltage on fault bus (volt)
I(a, b, c, n)_FLT_line label	Fault current (ampere)
CMD(a, b, c, n)_FLT_line label	Command for states of phase and ground breakers

PI Lines Control Panels

PI Line Control Panel

Line Data

The geometric data shown in Figures 7 - 6 to 7 - 7 are used to calculated a PI line.

Load File

An EMTP file that contains the physical parameters of the lines (Fig 7 - 2 and 7 - 3) or the resolve matrix by the external software of EMTP can be loaded automatically in the parameter form. Calculation of Electrical Parameters and Corresponding Control Panel

Calculation of Electrical Parameters

The calculation of electrical parameters of frequency constant parameter lines with their geometric parameters is done by using the Line Generator module in the mask of the line. Figure 7 - 9 shows the relevant part of the geometrical parameters.

Load a file into the Line Generator tab or enter your geometrical line parameters.
Select the transpositions options.
Run the program.
The electrical parameters are displayed in the Line Data report.

Transfer Electrical Parameters to HYPERSIM® Lines

The transfer of electrical parameters to HYPERSIM® is very simple.

In HYPERSIM® GUI, edition mode, draw a network with lines.
Go to the Line Generator tab, in the mask of your line.
To transfer electrical parameters, enter the parameters line.
Load parameters and Apply.
See the parameters in the report log.

HYPERSIM Documentation

PI Lines and PI Lines with Fault