Patent ID: 7502696

Claim:
A system for detecting a power system condition of a power system, the system comprising: a first intelligent electronic device operatively coupled to the power system at a first power system location, the first intelligent electronic device configured to calculate a first measured time value based on a frequency dependant parameter measured at the first power system location, to compare the first measured time value to a reference time value to form a first time error, and to transmit the first time error; a second intelligent electronic device operatively coupled to the power system at a second power system location to the first power system location, the second intelligent electronic device configured to calculate a second measured time value based on the frequency dependent parameter measured at the second power system location, to compare the second measured time value to the reference time value to form a second time error, and to transmit the second time error; and a third intelligent electronic device operatively coupled to the first and second intelligent electronic device, the third intelligent electronic device configured to receive and compare the first time error and the second time error to form a time differential error, to map the time differential error back to the first and second power system location, and to compare the time differential error to a predetermined threshold, the comparison determinative of the power system condition.