Power management method and system

• US 20040212512A1
• Filed: 02/27/2004
• Published: 10/28/2004
• Est. Priority Date: 08/30/2001
• Status: Active Grant

• Current Assignee: William L. Stewart
• Original Assignee: William L. Stewart
• Inventors: Stewart, William L.
• Granted Patent: US 7,132,950 B2
• Time in Patent Office: Days
• US Class Current: 340/657
• CPC Class Codes: G01R 15/142 Arrangements for simultaneous measurements of several parameters employing techniques covered by groups G01R15/14 - G01R15/26
• CPC Class Codes: G01R 15/181 using coils without a magnetic core, e.g. Rogowski coils

Abstract

The present invention provides a new application for an inductive coupler (12) used proximate a power transmission line (14). The magnetic field based power measurement method and system discussed herein in unique and differs from the prior technology by using near-real time intervals and periods that occur systemically in parallel with electrical systems rather than an accumulated period with little or no active capacity or proactive features. The inductive coupler (12) described herewith is used to collect, measure, and/or extract electromagnetic changes.

Claims

1. A power management system comprising:

a sensor positioned adjacent an electrical transmission line carrying alternating current, the sensor comprising at least two measurement elements configured to generate a signal proportional to the magnitude of changes in the electro magnetic field surrounding the transmission line; and

a system for processing the signals generated by the elements, the system processing the signals and generating an output that indicates changes in the condition of the power transmission line on a real time basis.

2. The power management system of claim 1 wherein the system for processing the signals include a computer and a database including historical data for the transmission line.

3. The power management system of claim 2 further comprising a data base including one or more grid maps, the computer using the grid map to generate a graphical representation of a power distribution system connected to the transmission line including the location of the source of the change in condition of the transmission line.

4. The power management system of claim 3 further comprising a database including topographical information for the geographic area served by the power distribution system, the computer using the topographical information to generate a graphical representation of the power distribution system including the topology of the geographical area covered by the power distribution system.

5. The power management system of claim 1 wherein sensor generates a signal proportional to a transient voltage on the power transmission line.

6. The power management system of claim 1 wherein the sensor generates a signal proportional to a harmonic voltage on the power line.

7. The power management system of claim 1 where the first measurement element is configured to generate an output that is phase shifted relative to the output of the second measurement element.

8. The power management system of claim 2 wherein the historical database includes data representing a previously measured transient on the power transmission line and the identify of the source of the transient.

9. A sensor configured to be positioned adjacent and parallel to an electrical transmission line carrying alternating current, comprising:

a casing;

a first electrical conductor disposed inside the casing having at least one turn therein to provide a pair of parallel linear segments of unequal length each extending in a lengthwise direction of the sensor;

a second electrical conductor in the form of a coil disposed around the first conductor;

a first lead connected to the first conductor for conducting a signal from the first conductor through the casing to an external signal analyzer; and

a second lead connected to the second conductor for conducting a signal from the second conductor through the casing to an external signal analyzer.

10. The sensor of claim 9, wherein the first conductor comprises a pair of parallel coils spaced apart in the lengthwise direction of the sensor and a segment connecting the coils.

11. The sensor of claim 10, wherein axes of the pair of parallel coils are set at an angle in the range of 10 to 14 degrees relative to the lengthwise direction of the sensor.

12. The sensor of claim 10, wherein the first conductor has at least six turns at one end thereof providing at least seven parallel segments of different lengths effective for monitoring a range of emissions from the transmission line.

13. The sensor of claim 12, wherein the case comprises a solid cylinder made of electrically insulating plastic in which the first and second conductors are embedded.