METHOD AND SYSTEM FOR MONITORING PARTIAL DISCHARGE WITHIN AN ELECTRIC GENERATOR
First Claim
1. A method of monitoring partial discharge in an electric iso-phase bus, comprising:
- arranging a first high frequency electrical sensor at least partially circumferentially surrounding a first conductor of the bus, wherein the first sensor has an input lead and an output lead;
arranging a second high frequency electrical sensor at a distance from the first sensor relative to an axial direction of the bus, at least partially circumferentially surrounding the first conductor of the bus, wherein the second sensor has an input lead and an output lead;
differentially connecting the first and second sensors to operate in a differential mode, wherein the output lead of the first sensor is connected to the output lead of the second sensor;
electrically coupling the input leads of the first and second sensors to an electrical measurement device;
measuring a sensor voltage by the measuring device where the voltage is induced in the first and the second sensors by a current flow of the iso-phase bus; and
monitoring the first and second measured voltages by a monitoring device for a transient voltage pulse, wherein the monitoring device determines if the transient voltage pulse is the result of partial discharge activity of a specific electric generator connected to the bus.
2 Assignments
0 Petitions
Accused Products
Abstract
Electrical generators used for power generation typically operate at high voltage. The High operating voltage results in a severe electrical stress environment for the generator conductor insulation system. The high electrical stress cal lead to a phenomena such as corona, partial discharge and arcing that can cause damage to the insulation and conductors. Disclosed is a novel method and system of detecting partial discharge activity within an electric generator. The method employs at least two Rogowski loops non-contactingly surrounding individual iso-phase bus conductors, where the loops are wired in differential mode to detect fast moving electrical pulses indicative of partial discharge.
10 Citations
20 Claims
-
1. A method of monitoring partial discharge in an electric iso-phase bus, comprising:
-
arranging a first high frequency electrical sensor at least partially circumferentially surrounding a first conductor of the bus, wherein the first sensor has an input lead and an output lead; arranging a second high frequency electrical sensor at a distance from the first sensor relative to an axial direction of the bus, at least partially circumferentially surrounding the first conductor of the bus, wherein the second sensor has an input lead and an output lead; differentially connecting the first and second sensors to operate in a differential mode, wherein the output lead of the first sensor is connected to the output lead of the second sensor; electrically coupling the input leads of the first and second sensors to an electrical measurement device; measuring a sensor voltage by the measuring device where the voltage is induced in the first and the second sensors by a current flow of the iso-phase bus; and monitoring the first and second measured voltages by a monitoring device for a transient voltage pulse, wherein the monitoring device determines if the transient voltage pulse is the result of partial discharge activity of a specific electric generator connected to the bus. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A non-contact iso-phase bus partial discharge monitoring system, comprising:
-
a sensor arranged coaxially surrounding and spaced from a conductor of the bus; formed from an insulated wire having a first wire end and a second wire end opposite the first end, and wrapped around a common axis to form a plurality of closed loops where the first and second ends form leads of the sensor; an electrical measurement device electrically connected to the sensor leads that measures a voltage of the sensor, where the sensor voltage is proportional to a rate of change of the current of the bus; and a monitoring device that monitors the sensor voltage for high frequency transient electrical pulses. - View Dependent Claims (13, 14, 15, 16, 17)
-
-
18. An inductive high voltage iso-phase bus current monitoring system, comprising:
-
an inductive non-contact sensor having a first sensor lead and a second sensor lead arranged coaxially around a conductor of a phase of the bus; an electrical input device electrically connected with the first and second sensor leads; and an evaluation unit that receives an output of the electrical input device and monitors an operating condition of the iso-phase bus for the presence of partial discharge. - View Dependent Claims (19, 20)
-
Specification