electricpy.fault.synmach_ifault

electricpy.fault.synmach_ifault(t, Ea, alpha, Xd, Xdp, Xdpp, Xqpp, Tdp, Tdpp, Ta, freq=60)[source]

Synchronous Machine Fault Current Calculator.

Given machine parameters, fault inception angle, and time at which to calculate fault current, this function will identify the complete (symmetrical, asymmetrical, and double frequency) fault current.

../_images/synmach_ifault_formula.png
Parameters:

  • t (float) – Time at which to calculate the fault current

  • Eq (float) – The internal machine voltage in per-unit-volts

  • alpha (float) – Fault inception angle (in degrees)

  • Xd (float) – The Xd (d-axis) reactance in per-unit-ohms

  • Xdp (float) – The X”d (d-axis transient) reactance in per-unit-ohms

  • Xdpp (float) – The X”d (d-axis sub-transient) reactance in per-unit-ohms

  • Xqpp (float) – The X”q (q-axis sub-transient) reactance in per-unit-ohms

  • Tdp (float) – The T’d (d-axis transient) time constant of the machine in seconds

  • Tdpp (float) – The T”d (d-axis sub-transient) time constant of the machine in seconds

  • Ta (float) – Armature short-circuit (DC) time constant in seconds

  • freq (float, optional) – System (electrical) frequency (in degrees), default=60

Returns:

ias – Synchronous machine fault current (symmetrical, asymmetrical, and double frequency component) in amps

Return type:

float