Electrical switching apparatus and protection apparatus determining thermal age of another apparatus or a number of insulators
First Claim
1. An electrical switching apparatus for another apparatus including a number of insulators, a number of temperature sensors operatively associated with said number of insulators, and a number of conductors operatively associated with said number of insulators, said electrical switching apparatus comprising:
- a number of separable contacts;
an operating mechanism structured to open and close said number of separable contacts;
a number of sensors structured to sense a number of currents flowing through said number of separable contacts and through said number of conductors;
a processor structured to input the sensed number of currents from said number of sensors; and
an output,wherein said processor is further structured to calculate at least one of;
(a) a thermal age of said another apparatus from a number of sensed temperatures from said number of temperature sensors, and (b) the thermal age of said another apparatus from said sensed number of currents, andwherein said output includes the thermal age of said another apparatus,wherein said processor is further structured to determine temperature of said another apparatus and to determine insulation life expectancy of said another apparatus from e(a+b(ln(TEMP))), wherein a, b and e are constants, ln is the natural logarithm, and TEMP is said determined temperature.
2 Assignments
0 Petitions
Accused Products
Abstract
An electrical switching apparatus is for another apparatus including a number of insulators, a number of temperature sensors operatively associated with the number of insulators, and a number of conductors operatively associated with the number of insulators. The electrical switching apparatus includes a number of separable contacts, an operating mechanism structured to open and close the separable contacts, a number of sensors structured to sense a number of currents flowing through the separable contacts and through the conductors, a processor structured to input the sensed currents from the sensors, and an output. The processor calculates at least one of: (a) a thermal age of the other apparatus from a number of sensed temperatures from the temperature sensors, and (b) the thermal age of the other apparatus from the sensed currents. The output includes the thermal age of the other apparatus.
17 Citations
20 Claims
-
1. An electrical switching apparatus for another apparatus including a number of insulators, a number of temperature sensors operatively associated with said number of insulators, and a number of conductors operatively associated with said number of insulators, said electrical switching apparatus comprising:
-
a number of separable contacts; an operating mechanism structured to open and close said number of separable contacts; a number of sensors structured to sense a number of currents flowing through said number of separable contacts and through said number of conductors; a processor structured to input the sensed number of currents from said number of sensors; and an output, wherein said processor is further structured to calculate at least one of;
(a) a thermal age of said another apparatus from a number of sensed temperatures from said number of temperature sensors, and (b) the thermal age of said another apparatus from said sensed number of currents, andwherein said output includes the thermal age of said another apparatus, wherein said processor is further structured to determine temperature of said another apparatus and to determine insulation life expectancy of said another apparatus from e(a+b(ln(TEMP))), wherein a, b and e are constants, ln is the natural logarithm, and TEMP is said determined temperature. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 16)
-
-
14. An electrical switching apparatus for another apparatus including a number of insulators, a number of temperature sensors operatively associated with said number of insulators, and a number of conductors operatively associated with said number of insulators, said electrical switching apparatus comprising:
-
a number of separable contacts; an operating mechanism structured to open and close said number of separable contacts; a number of sensors structured to sense a number of currents flowing through said number of separable contacts and through said number of conductors; a processor structured to input the sensed number of currents from said number of sensors; and an output, wherein said processor is further structured to calculate at least one of;
(a) a thermal age of said another apparatus from a number of sensed temperatures from said number of temperature sensors, and (b) the thermal age of said another apparatus from said sensed number of currents,wherein said output includes the thermal age of said another apparatus, wherein said processor is further structured to determine a temperature from an average of the number of sensed temperatures over a predetermined time period or an average of the sensed number of currents over the predetermined time period, wherein said processor is further structured to determine an insulation life expectancy from the determined temperature, wherein said processor is further structured to determine a thermal age used in the predetermined time period from a standard insulation life expectancy of said another apparatus at full operating temperature divided by said determined insulation life expectancy, and wherein said processor is further structured to accumulate the thermal age of said another apparatus from a previously accumulated thermal age plus said thermal age used in the predetermined time period.
-
-
17. A protection relay for an apparatus including a number of insulators and a number of temperature sensors operatively associated with said number of insulators, said protection relay comprising:
-
an input structured to input a number of sensed temperatures from said number of temperature sensors; a processor structured to calculate a thermal age of said number of insulators from said number of sensed temperatures; and an output including the thermal age of said number of insulators, wherein said processor is further structured to calculate an average temperature of said apparatus from an average of said number of sensed temperatures from said number of temperature sensors over a predetermined time; and
wherein said processor is further structured to determine insulation life expectancy of said number of insulators from e(a+b(ln(TEMP))), wherein a, b and e are constants, ln is the natural logarithm, and TEMP is said average temperature. - View Dependent Claims (18)
-
-
19. A protection relay for an apparatus including a number of insulators and a number of conductors operatively associated with said number of insulators, said protection relay comprising:
-
a number of sensors structured to sense a number of currents flowing through said number of conductors; a processor structured to input the sensed number of currents from said number of sensors and to calculate a thermal age of said number of insulators from said sensed number of currents; and an output including the thermal age of said number of insulators, wherein said processor is further structured to calculate an estimated temperature of said apparatus from (IAVG/INP)2×
(TCLASS−
ambient temperature)+ambient temperature;
wherein IAVG is average RMS current of said sensed number of currents;
wherein INP is name plate current of said apparatus;
wherein TCLASS is temperature class of said number of insulators; and
wherein said processor is further structured to determine insulation life expectancy of said number of insulators from e(a+b(ln(TEMP))), wherein a, b and e are constants, ln is the natural logarithm, and TEMP is said estimated temperature. - View Dependent Claims (20)
-
Specification