Capacitive voltage-sensor assembly

Abstract

A capacitive voltage sensor includes an electrode extending along a longitudinal axis, a tubular portion including a layer of electrically insulating material, a layer of electrically conductive material positioned radially inward of the layer of electrically insulating material in a direction toward the longitudinal axis, and an outer shield configured as a latticelike network and positioned radially outward of the layer of electrically insulating material in a direction away from the longitudinal axis. The layer of electrically conductive material, the layer of electrically insulating material, and the outer shield each surround and is spaced in a direction radially outward from the longitudinal axis and from a portion of the electrode. A mass of dielectric insulating material at least partially encapsulating the electrode and the tubular portion and fills through holes formed in the latticelike network of the outer shield.

What is claimed is: 
     
         1 . A capacitive voltage sensor comprising:
 an electrode extending along a longitudinal axis;   a tubular portion including
 a layer of electrically insulating material, 
 a layer of electrically conductive material positioned radially inward of the layer of electrically insulating material in a direction toward the longitudinal axis, and 
 an outer shield configured as a latticelike network and positioned radially outward of the layer of electrically insulating material in a direction away from the longitudinal axis, 
 wherein the layer of electrically conductive material, the layer of electrically insulating material, and the outer shield each surrounds and is spaced in a direction radially outward from the longitudinal axis and from a portion of the electrode; and 
   a mass of dielectric insulating material at least partially encapsulating the electrode and the tubular portion,   wherein the mass of dielectric material fills through holes formed in the latticelike network of the outer shield,   wherein the layer of electrically insulating material is configured to support the layer of electrically conductive material, and   wherein the layer of electrically conductive material is positioned intermediate between a first axial end of the outer shield and a second opposite axial end of the outer shield such that a length of the layer of electrically conductive material along the longitudinal axis is less than a length of the outer shield along the longitudinal axis.   
     
     
         2 . The capacitive voltage sensor assembly of  claim 1 , wherein the layer of electrically insulating material and the layer of electrically conductive material comprise a printed circuit board. 
     
     
         3 . The capacitive voltage sensor assembly of  claim 1 , wherein the length of the layer of electrically conductive material is coextensive with a length of the layer of electrically insulating material along the longitudinal axis. 
     
     
         4 . The capacitive voltage sensor assembly of  claim 1 , wherein a length of the layer of electrically insulating material along the longitudinal axis is less than the length of the outer shield. 
     
     
         5 . The capacitive voltage sensor assembly of  claim 1 , wherein the layer of electrically insulating material and the layer of electrically conductive material are configured to form a monolithic body fixed to an inner surface of the outer shield. 
     
     
         6 . A capacitive voltage sensor comprising:
 an electrode extending along a longitudinal axis;   a tubular portion including
 a layer of electrically insulating material, 
 a layer of electrically conductive material positioned radially inward of the layer of electrically insulating material in a direction toward the longitudinal axis, and 
 a flexible outer shield configured as a latticelike network and positioned radially outward of the layer of electrically insulating material in a direction away from the longitudinal axis, 
 wherein the layer of electrically conductive material, the layer of electrically insulating material, and the outer shield each surrounds and is spaced in a direction radially outward from the longitudinal axis and from a portion of the electrode; and 
   a mass of dielectric insulating material at least partially encapsulating the electrode and the tubular portion, wherein the mass of dielectric material fills through holes formed in the latticelike network of the outer shield,   wherein the layer of electrically insulating material is configured to support the layer of electrically conductive material to form a monolithic body fixed to an inner surface of the outer shield,   wherein the layer of electrically insulating material and the layer of electrically conductive material are positioned intermediate between a first axial end of the outer shield and a second opposite axial end of the outer shield such that a length of the layer of electrically conductive material along the longitudinal axis is less than a length of the outer shield along the longitudinal axis and a length of the layer of electrically conductive material along the longitudinal axis is less than the length of the outer shield, and   wherein the length of the layer of electrically conductive material is coextensive with the length of the layer of electrically insulating material.   
     
     
         7 . The capacitive voltage sensor assembly of  claim 6 , wherein the latticelike network defines a first plurality of through holes, the layer of electrically insulating material includes a second plurality of through holes, and the layer of electrically conductive material includes a third plurality of through holes, and wherein the first plurality of through holes is in axial communication with the second and third pluralities of through holes. 
     
     
         8 . The capacitive voltage sensor assembly of  claim 7 , wherein the second plurality of through holes comprises a first row of circumferentially spaced through holes and a second row of circumferentially spaced through holes and at least one through hole of the first row is aligned with a through hole of the second row in a direction parallel to the longitudinal axis, and wherein the third plurality of through holes comprises a first row of circumferentially spaced through holes and a second row of circumferentially spaced through holes and wherein at least one through hole of the first row is aligned with a through hole of the second row in a direction parallel to the longitudinal axis, and wherein at least one through hole of the second plurality of through holes is aligned with a through hole of the third plurality of through holes. 
     
     
         9 . The capacitive voltage sensor assembly of  claim 8 , wherein the second plurality of through holes of the layer of electrically insulating material and the third plurality of through holes of the layer of electrically conductive material are configured as elongated slits that have a length extending in a direction parallel to the longitudinal axis; 
     
     
         10 . The capacitive sensor element of  claim 9 , wherein each through hole in the second plurality of through holes has a first perimeter and each through hole in the third plurality of through holes has a second perimeter, and wherein the first perimeter is less than the second perimeter. 
     
     
         11 . The capacitive voltage sensor assembly of  claim 10 , wherein the first axial end of the outer shield is open and the second opposite axial end of the outer shield is closed. 
     
     
         12 . A capacitive voltage sensor assembly comprising:
 an electrode extending along a longitudinal axis;   a flexible tubular shield surrounding and spaced in a direction radially outward from the longitudinal axis and from a portion of the electrode, wherein the tubular shield includes a first plurality of through holes;   a circular sensor element positioned radially inward of the tubular shield,
 wherein the circular sensor element includes a printed circuit board having a layer of electrically insulating material and a layer of electrically conductive material, 
 wherein the circular sensor element surrounds and is spaced in a direction radially outward from the longitudinal axis and from a portion of the electrode, 
 wherein the layer of electrically insulating material includes a second plurality of through holes comprising a first row of circumferentially spaced through holes and a second row of circumferentially spaced through holes and at least one through hole of the first row is aligned with a through hole of the second row in a direction parallel to the longitudinal axis, 
 wherein the layer of electrically conductive material includes a third plurality of through holes comprising a first row of circumferentially spaced through holes and a second row of circumferentially spaced through holes and wherein at least one through hole of the first row is aligned with a through hole of the second row in a direction parallel to the longitudinal axis, and wherein at least one through hole of the second plurality of through holes is aligned with a through hole of the third plurality of through holes, 
 wherein the second plurality of through holes of the layer of electrically insulating material and the third plurality of through holes of the layer of electrically conductive material are configured as elongated slits that have a length extending in a direction parallel to the longitudinal axis; and 
   a mass of dielectric material surrounding the tubular shield and the circular sensor element, wherein the mass of dielectric insulating material fills through holes of the first, second, and third plurality of through holes,   wherein the layer of electrically insulating material and the layer of electrically conductive material form a monolithic body fixed to an inner surface of the tubular shield, and   wherein a width of each through hole of the second plurality of through holes is less than a width of each through hole of the third plurality of through holes.   
     
     
         13 . The capacitive voltage sensor assembly of  claim 12 , wherein the first plurality of through holes defines a latticelike network, and wherein the first plurality of through holes is in axial communication with the second and third plurality of through holes. 
     
     
         14 . The capacitive sensor element of  claim 12 , wherein each through hole in the second plurality of through holes has a first perimeter and each through hole in the third plurality of through holes has a second perimeter, and wherein the first perimeter is less than the second perimeter. 
     
     
         15 . The capacitive voltage sensor of  claim 12 , wherein a first axial end of the outer shield is open and a second opposite axial end of the outer shield is closed. 
     
     
         16 . The capacitive voltage sensor of  claim 12 , wherein the layer of electrically conductive material is positioned intermediate a first axial end of the tubular shield and a second opposite axial end of the tubular shield such that a length of the layer of electrically conductive material along the longitudinal axis is less than a length of the tubular shield along the longitudinal axis. 
     
     
         17 . The capacitive voltage sensor of  claim 16 , wherein the layer of electrically insulating material is positioned intermediate the first axial end of the tubular shield and the second opposite axial end of the tubular shield such that a length of the layer of electrically insulating material along the longitudinal axis is less than the length of the tubular shield along the longitudinal axis. 
     
     
         18 . The capacitive voltage sensor of  claim 12 , wherein a length of the layer of electrically conductive material along the longitudinal axis is coextensive with a length of the layer of electrically insulating material along the longitudinal axis. 
     
     
         19 . The capacitive voltage sensor of  claim 12 , wherein the width of each of the through holes of the second plurality of through holes is less than a width of each of the through holes of the first plurality of through holes. 
     
     
         20 . The capacitive voltage sensor of  claim 12 , wherein each through hole of the second plurality of through holes is aligned with a through hole of the third plurality of through holes, and wherein a perimeter of each through hole of the second plurality of through holes is less than a perimeter of each through hole of the third plurality of through holes such that an annulus of insulating material is formed between the perimeter of each through hole of the second plurality of through holes and the perimeter of each through hole of the third plurality of through holes.