Patent ID: 6442493
Filing Date: 2002-08-27
Classification: G01R,H02H

Abstract:
A method of detecting a fault on a monitored section of an electric transmission line, comprising the steps of:detecting a fault at a location on the monitored section; measuring, with a first measuring unit at a first end of the monitored section, a first current value and a first voltage value on the measured section when the fault is detected; measuring, with a second measuring unit at a second end of the monitored section, a second current value and a second voltage value on the measured section when the fault is detected; generating, with the first measuring unit, a first release signal and a first direction signal as a function of the first current value and the first voltage value, the first release signal and the first direction signal indicating a first characterization of the detected fault; generating, with the second measuring unit, a second release signal and a second direction signal as a function of the second current value and the second voltage value, the second release signal and the second direction signal indicating a second characterization of the detected fault; transmitting the first direction signal from the first measuring unit to the second measuring unit over a low-transmission-capacity data line; transmitting the second direction signal from the second measuring unit to the first measuring unit over the low-transmission-capacity data line; after generating the first release signal, generating by the first measuring unit a first intermediate parameter for calculating the location of the fault; after generating the second release signal, generating by the second measuring unit a second intermediate parameter for calculating the location of the fault; transmitting the first intermediate parameter from the first measuring unit to the second measuring unit over the low-transmission-capacity data line; transmitting the second intermediate parameter from the second measuring unit to the first measuring unit over the low-transmission-capacity data line; generating a first measured quantity in the first measuring unit as a function of the first intermediate parameter and the second intermediate parameter, the first measured quantity indicating the location of the fault; and generating a second measured quantity in the second measuring unit as a function of the second intermediate parameter and the first intermediate parameter, the second measured quantity indicating the location of the fault.