.PowerSystems.AC3ph.ImpedancesYD

Impedance and admittance one terminal, Y and Delta topology

Information

Contains lumped impedance models for Y and Delta topology.

General relations see 'Impedances'.

All elements allow the choice between Y- and Delta-topology.
The impedance parameters are defined 'as seen from the terminals', directly relating terminal voltage and terminal current. With this definition same parameters lead to same network properties, independent of topology. The necessary scaling is performed automatically.

In Delta-topology the conductor voltage is sqrt(3) higher, the current sqrt(3) lower, compared to the terminal voltage and current. Therefore the impedance relating conductor current and voltage is a factor 3 larger, the admittance a factor 1/3 smaller than the impedance and admittance as seen from the terminal.

If impedance parameters are known for the WINDINGS, choose:

  input values impedance parameters = (winding values of impedance parameters)/3

In dq0-representation the following relations hold between
terminal-voltage term.v and -current term.i on the one hand
and conductor-voltage v and -current i on the other:

Y-topology:

  v = term.v - {0, 0, sqrt(3)*v_n}: voltage between terminal and neutral point
  term.i = i
  i_n = sqrt(3)*term.i[3]

Delta-topology:

  v[1:2] = sqrt(3)*R30*term.v[1:2]: voltage between phase-terminals
  v[3] = 0
  term.i[1:2] = sqrt(3)*transpose(R30)*i[1:2]
  term.i[3] = 0

with R30 = rotation_30deg
(Alternative solutions corresponding to permuted phases are R-90 and R150 instead of R30).

Contents

Name Description
 Resistor Resistor, 3-phase dq0
 Conductor Conductor, 3-phase dq0
 Inductor Inductor with series resistor, 3-phase dq0
 Capacitor Capacitor with parallel conductor, 3-phase dq0
 ResistorNonSym Resistor non symmetric, 3-phase dq0
 InductorNonSym Inductor with series resistor non symmetric, 3-phase dq0
 CapacitorNonSym Capacitor with parallel conductor non symmetric, 3-phase dq0
 Varistor Varistor, 3-phase dq0
 Partials Partial models

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