Method and system for autonomous measurement of transmission line EMF for pipeline cathodic protection systems

Abstract

An active cathodic analysis protection system employs local monitors that detect the electromagnetic fields near the transmission line. This yields a set of electromagnetic field (EMF) point readings along the transmission line. From this information a three dimensional (3D) EMF field estimation is determined. EMF field estimation is used in combination with a system geometry model, which includes the transmission line geometry, the geometry of the monitors with respect to the transmission line, and the pipeline geometry.

What is claimed is: 
     
         1 . A cathodic protection system, comprising:
 electromagnetic field monitors installed along a transmission line;   a controller for estimating cathodic protection for a pipeline based on telemetry data from the electromagnetic field monitors; and   a cathodic protection system for applying the cathodic protection to the pipeline under the control of the controller.   
     
     
         2 . The system as a claimed in  claim 1 , wherein the controller estimates cathodic protection using a system geometry model. 
     
     
         3 . The system as a claimed in  claim 2 , wherein the system geometry model includes a geometry of the transmission line, a geometry of the monitors, and a geometry of the pipeline. 
     
     
         4 . The system as a claimed in  claim 2 , wherein a longitudinal pipeline EMF exposure profile is generated based on survey geometry data sources and the system geometry model. 
     
     
         5 . The system as a claimed in  claim 1 , further comprising generating a phase order for the transmission line. 
     
     
         6 . A cathodic protection method, comprising:
 installing electromagnetic field monitors along a transmission line;   estimating cathodic protection for a pipeline based on telemetry data from the electromagnetic field monitors; and   applying the cathodic protection to the pipeline with a cathodic protection system.   
     
     
         7 . The method as a claimed in  claim 6 , further comprising estimating cathodic protection using a system geometry model. 
     
     
         8 . The method as a claimed in  claim 7 , wherein the system geometry model includes a geometry of the transmission line, a geometry of the monitors, and a geometry of the pipeline. 
     
     
         9 . The method as a claimed in  claim 7 , further comprising generating the system geometry model by surveying along the transmission line and transverse to the transmission line. or generating the system geometry model by surveying along a pipeline right-of-way and transverse to the pipeline right-of-way. 
     
     
         10 . The method as a claimed in  claim 6 , further comprising generating a phase order for the transmission line. 
     
     
         11 . A transmission line monitoring system, comprising:
 local monitors installed along a transmission line;   a monitor server system receiving telemetry data from the local monitors and using a system geometry model to determine interference in adjacent to the transmission line.   
     
     
         12 . A transmission line monitoring method, comprising:
 Detecting magnetic fields and electric fields along a transmission line with local monitors installed in a right-of-way of the transmission line;   telemetry data from the local monitors and using a system geometry model to determine interference in adjacent to the transmission line.   
     
     
         13 . A local monitor comprising:
 a three axis magnetic field transducer;   a three axis electric field transducer;   a wireless data communication section; and   a local controller for monitoring the three axis magnetic field transducer and the three axis electric field transducer and generating transmission line telemetry data for transmission to a monitor server system using the wireless data communication section.   
     
     
         14 . The local monitor of  claim 13 , further comprising an ambient temperature sensor and an internal temperature sensor. 
     
     
         15 . The local monitor of  claim 13 , further comprising a GPS receiver for receiving position and time information. 
     
     
         16 . The local monitor of  claim 13 , wherein the local controller provides timestamps from the GPS receiver with the telemetry data to the monitor server system to determine fault events. 
     
     
         17 . The local monitor of  claim 13 , wherein the monitor server system localizes the fault events using the timestamps and the telemetry data. 
     
     
         18 . A transmission line monitor method, comprising:
 detecting a magnetic field near a transmission line;   detecting an electric field near the transmission line;   generating transmission line telemetry data for wireless transmission to a monitor server system.