Fault detection in an electric power system

A fault protection system for an electric power system, the fault protection system comprising:

• processing circuitry configured to:
• obtain a differential measurement signal that indicates, as a function of time, a difference between currents or voltages measured at two or more terminals or boundaries of a fault protection zone of the electric power system;
• generate a fault detection signal by cross-correlating the differential measurement signal with a reference signal, wherein the reference signal is the differential measurement signal that is expected upon occurrence of a fault internal to the fault protection zone;
• and
• perform fault detection, for detecting the fault internal to the fault protection zone, as a function of the fault detection signal.

A method comprising:

• obtaining a current or voltage measurement signal containing embedded evidence of a short-circuit fault in a fault protection zone of an electric power system;
• generating a fault detection signal by cross-correlating the current or voltage measurement signal with a reference signal, wherein the reference signal is an expected current or voltage measurement signal that is expected upon occurrence of the short-circuit fault in the fault protection zone;
• and
• performing fault detection, for detecting a fault internal to the fault protection zone, as a function of the fault detection signal.