Patent ID: 11873403
Assignee: 3M INNOVATIVE PROPERTIES COMPANY
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC C  H | IPC C  H

Claim 0:
1. A composite article consisting of an electric field grading composition disposed on a surface of a conductive substrate, wherein the conductive substrate comprises a switch housing or at least a portion of an electrical cable splice, electrical cable termination, surge arrester for electrostatic discharge protection, or a transformer insulation, and wherein the electric field grading composition comprises a particulate cupric oxide dispersed in a matrix material, wherein the electric field grading composition has a threshold voltage, a breakdown voltage, and exhibits a reversible electric field switchable current-voltage relationship that substantially follows the equation:

I=kVα

wherein:
I is current in amperes;
k is a constant greater than 0;
V is applied voltage in volts, wherein V is between the threshold voltage and the breakdown voltage, inclusive; and
α is a real number greater than 1.