Patent ID: 11933833
Assignee: APLICACIONES TECNOLOGICAS, S.A.
Field: Measurement (Instruments)
Classification: CPC G  Y | IPC G

Claim 4:
5. Fault detection system (800) for a medium voltage circuit comprising sets of an electric power distribution cable (205), a first transformation center (210) comprising a first transformer and a first grounding conductor (603), a first grounding system comprising a first grounding resistor (RPAT1) connected to the first transformer through the first grounding conductor (603), the first transformation center (210) connected to a first end of the cable (205); and
a second transformation center (220) comprising a second transformer and a second grounding conductor (603), a second grounding system comprising a second grounding resistor (RPAT2) connected to the second transformer through the second grounding conductor (603), the second transformation center (220) connected to a second end of the cable (205), the fault detection system (800) comprises:
a set of sensors (600) comprising wireless communication means, and
a processing unit (818),

wherein a first sensor (600) comprises means (602) for the connection to the first grounding conductor (603) and is configured to:
detect a cable fault (205) by detecting a threshold current value through the first grounding conductor (603), wherein in case of fault identification:
measuring a first current value Imed1 through the first grounding conductor (603);
obtaining the value of the first resistor (RPAT1); and
transmitting Imed1 and (RPAT1) to the processing unit (818),

wherein a second sensor (600) comprises means (602) for the connection to the second grounding conductor (603), and is configured to:
detect a cable fault (205) by detecting a threshold current value through the second grounding conductor (603), wherein in case of fault identification:
measuring a second current value Imed2 through the second grounding conductor (603);
obtaining the value of the second resistor (RPAT2); and
transmitting Imed2 and (RPAT2) to the processing unit (818);

wherein the processing unit (818) stores instructions for:
calculating a relative distance d1 from a point on the cable (205) where the fault occurs to the first transformation center (210), such that:, d
   1
  
  =
  
   
    
     
      I
      
       med
       ⁢
       2
      
     
     ·
     
      R
      
       PAT
       ⁢
       2
      
     
    
    -
    
     
      I
      
       med
       ⁢
       1
      
     
     ·
     
      R
      
       PAT
       ⁢
       1
      
     
    
   
   
    (
    
     
      I
      
       med
       ⁢
       2
      
     
     +
     
      I
      
       med
       ⁢
       1
      
     
    
    )
   
  
 

calculating a distance d2 from the point on the cable (205) where the fault occurs to the second transformation center (210);, d
   2
  
  =
  
   
    
     
      I
      
       med
       ⁢
       2
      
     
     ·
     
      (
      
       1
       -
       
        R
        
         PAT
         ⁢
         2
        
       
      
      )
     
    
    +
    
     
      I
      
       med
       ⁢
       1
      
     
     ·
     
      (
      
       1
       +
       
        R
        
         PAT
         ⁢
         1
        
       
      
      )
     
    
   
   
    (
    
     
      I
      
       med
       ⁢
       2
      
     
     +
     
      I
      
       med
       ⁢
       1
      
     
    
    )
   
  
 

identifying the location of the cable fault (205) based on the distances d1 and d2.