Patent ID: 11875919
Assignee: 3M INNOVATIVE PROPERTIES COMPANY
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A multilayer electric field grading article comprising:
a first layer comprising a first electric field grading composition, the first electric field grading composition comprising first particles dispersed in a first matrix material, wherein the first layer has a first degree of nonlinearity that occurs between a first onset voltage and a first breakdown voltage;
a second layer disposed on the first layer and comprising a second electric field grading composition, the second electric field grading composition comprising second particles dispersed in a second matrix material, wherein the second layer has a second degree of nonlinearity that occurs between a second onset voltage and a second breakdown voltage, and wherein the second particles are compositionally different from the first particles; and
a discrete interface formed by intimate contact of the first and second layers,
wherein the first and second layers taken together have a combined onset voltage that is higher than the first and second onset voltages, and wherein the first and second layers taken together have a greater combined degree of nonlinearity than each of the first and second degrees of nonlinearity taken individually.