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Phase to phase fault

transmission line FEA simulation, short circuit current magnetic field

Phase to phase fault is one of the most widespread damages of the transmission lines in electrical networks (15-20 % from total number of failures). This model shows how to simulate the phase to phase fault in QuickField.

Problem Type
Plane-parallel problem of transient magnetics.

Geometry

Aluminum Conductor Steel Reinforced (ACSR):

Line-to-line short circuit:

Given
Rated voltage (RMS) U_rated = 110 kV;
Rated current (RMS) I_rated = 440 A;
Line length l = 20 km;
Loading parameters R_load = 100 Ohm; L_load = 0.23 H.

Task
Determine the transient process currents after a short circuit occurred. Find the electromagnetic forces acting on the lines during this process.

Solution
To solve this problem it is necessary to simulate both field part and circuit part. The scheme of connection of power supply phase windings, loading, elements of the circuit and short-circuit bridge is presented in the circuit model, created by the QuickField Circuit Editor.

Short-circuit bridge is a QuickField block with the resistance which varies in time. This dependence is implemented using the electrical conductivity as a function of the temperature, which is also function of time - as σ(T(t)) function.

Results
Short-circuit current (amplitude) I_max = 7000 A.
Electromagnetic force of interaction between phases A and B F_A-B = 1780 N/km.

Illustration of the short-circuit currents in the transmission line:

• Video: Phase to phase fault
  
• Watch online on YouTube.
• View simulation report in PDF
• Download simulation files (files may be viewed using any QuickField Edition).