Triple and Quadruple PI Lines

The models of triple and quadruple PI lines are a generalization of the coupled PI line model. They represent respectively 3 and 4 three phase circuits. The quadruple model with fault is also available.

Triple and Quadruple PI Lines Icons and Diagrams

Triple PI Line Icon and Diagram

Quadruple PI Line Icon and Diagram

Quadruple PI Line with Fault Icon and Diagram


Parameter Description


The parameters for triple and quadruple PI lines are the same as for those for simple PI lines, except that the dimensions of the R, L and C matrices representing the impedances and admittances of the conductors are 9x9 and 12x12. Since these matrices are large, the option that allows calculate the values of the parameters from EMTP or Inpurdue files is quite interesting; it allows users to avoid the tedious task of re-transcribing the values and possible resulting errors.

List of Available Signals


As for a coupled PI line, there is no line signal available for triple and quadruple PI lines. Only the fault signals are available.

Fault Signals

V(a, b, c)_FLT1_line labelVoltage on fault bus of line 1 (volt)
V(a, b, c)_FLT2_line labelVoltage on fault bus of line 2 (volt)
V(a, b, c)_FLT3_line labelVoltage on fault bus of line 3 (volt)
V(a, b, c)_FLT4_line labelVoltage on fault bus of line 4 (volt)
I(a, b, c, n)_FLT1_line labelFault current of line 1 (ampere)
I(a, b, c, n)_FLT2_line labelFault current of line 2 (ampere)
I(a, b, c, n)_FLT3_line labelFault current of line 3 (ampere)
I(a, b, c, n)_FLT4_line labelFault current of line 4 (ampere)
CMD(a, b, c, n)_FLT1_line labelCommand for states of phase and ground breakers of line1
CMD(a, b, c, n)_FLT2_line labelCommand for states of phase and ground breakers of line 2
CMD(a, b, c, n)_FLT3_line labelCommand for states of phase and ground breakers of line 3
CMD(a, b, c, n)_FLT4_line labelCommand for states of phase and ground breakers of line 4


Control Panels for PI Lines - Triple, Quadruple and Quadruple with Fault

Triple PI Line Control Panel

Quadruple PI Line Control Panel

Quadruple PI Line with Fault Control Panel


Line Data

Since these models are a generalization of the coupled PI line, the data are calculated in the same way.