Fiber optic temperature probe for oil-filled power transformers

Abstract

A temperature probe for use in oil-filled transformers comprises an optical fiber, a temperature sensitive member, and a protective cylindrical sheath. The optical fiber and the sensitive member are located in the protective sheath, and continuous longitudinal slit is defined along the length of the sheath to allow oil to flow therein. The optical fiber is mounted in and to the sheath using a bonding material and at a distance from the sheath. The sensitive member is adhesively mounted to the optical fiber, within the sheath, and at a distance thereof.

1 . A temperature probe for use in fluid-filled transformers, comprising an optical fiber, a temperature sensitive member, and a protective sheath, the optical fiber and the sensitive member being located in the protective sheath, the sheath defining at least one substantially longitudinal slit so as to allow fluid to flow into the sheath.  
   
   
       2 . A temperature probe as defined in  claim 1 , wherein the sheath is tubular.  
   
   
       3 . A temperature probe as defined in  claim 1 , wherein the slit is a single continuous slit.  
   
   
       4 . A temperature probe as defined in  claim 3 , wherein the continuous slit extends substantially a length of the protective sheath.  
   
   
       5 . A temperature probe as defined in  claim 1 , wherein the optical fiber is mounted in the sheath using a bonding material.  
   
   
       6 . A temperature probe as defined in  claim 5 , wherein the optical fiber is mounted with the bonding material at a distance from the sheath.  
   
   
       7 . A temperature probe as defined in  claim 1 , wherein the sensitive member is mounted to the optical fiber.  
   
   
       8 . A temperature probe as defined in  claim 7 , wherein the sensitive member is mounted substantially at a distal end of the optical fiber and at a distance from the sheath.  
   
   
       9 . A temperature probe comprising an optical fiber, a temperature sensitive member, and a protective sheath, the optical fiber and the sensitive member being located in the protective sheath.  
   
   
       10 . A temperature probe as defined in  claim 9 , wherein the sensitive member is mounted to the optical fiber within the sheath.  
   
   
       11 . A temperature probe as defined in  claim 10 , wherein the sensitive member is mounted substantially at a distal end of the optical fiber.  
   
   
       12 . A temperature probe as defined in  claim 10 , wherein the sensitive member is spaced from the sheath.  
   
   
       13 . A temperature probe as defined in  claim 10 , wherein the sensitive member is mounted to the optical fiber with an adhesive.  
   
   
       14 . A temperature probe as defined in  claim 9 , wherein the optical fiber is mounted to the sheath using a bonding material and at a distance from the sheath.  
   
   
       15 . A temperature probe comprising an optical fiber, a temperature sensitive member, and a protective sheath, the sensitive member being mounted to the optical fiber and the optical fiber being mounted to the protective sheath.  
   
   
       16 . A temperature probe as defined in  claim 15 , wherein the optical fiber is mounted in the sheath using a bonding material.  
   
   
       17 . A temperature probe as defined in  claim 16 , wherein the optical fiber is mounted with the bonding material at a distance from the sheath.  
   
   
       18 . A temperature probe as defined in  claim 15 , wherein the sensitive member is spaced from the sheath.  
   
   
       19 . A temperature probe as defined in  claim 15 , wherein an inside surface of the sheath is treated for better adherence of the bonding material thereto.  
   
   
       20 . A temperature probe as defined in  claim 19 , wherein the inside surface of the sheath is at least one of chemically-etched and mechanically-modified.