Fault monitoring method for multi-port internal passive load-free probabilistic load flow electric network

A fault monitoring method for a multi-port internal passive load-free probabilistic load flow (PLF) electric network, comprising:

• connecting the PLF electric network to ports via conductors, with current transformers installed on the conductors;
• transforming currents from the current transformers into voltages, and then converting the voltages into pulses by a voltage-to-frequency conversion (VFC) circuit;
• transmitting the pulses via optical fiber to a comparison module;
• calculating an algebraic sum of all pulse counts corresponding to the current transformers by the comparison module, wherein it is stipulated that when an installation direction of the current transformer is the same as a direction of the port pointing to the PLF electric network, the pulse count is positive, and when the installation direction of the current transformer is opposite to the direction of the port pointing to the PLF electric network, the pulse count is negative;
• or it is stipulated that when the installation direction of the current transformer is the same as the direction of the port pointing to the PLF electric network, the pulse count is negative, and when the installation direction of the current transformer is opposite to the direction of the port pointing to the PLF electric network, the pulse count is positive;
• and
• determining, by the comparison module, that a fault has occurred within the PLF electric network when the algebraic sum exceeds a threshold.