Patent ID: 11885843
Assignee: HITACHI ENERGY LTD
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 6:
7. The system according to claim 6, wherein the instantaneous comparison voltage value is calculated by:, u
    
      q
      ⁢
      _
      ⁢
      k
    
  
  =
  
    
      
        m
        1
      
      ·
      
        u
        k
      
    
    +
    
      
        m
        2
      
      ·
      
        (
        
          
            R
            ·
            
              i
              k
            
          
          +
          
            L
            ·
            
              
                di
                k
              
              dt
            
          
        
        )
      
    
  

wherein ures_k represents the instantaneous comparison voltage value at instant k, uk represents the sampled value of the voltage at instant k, ik represents the sampled value of the current at instant k, R and L, respectively, represent the resistance value of the resistor and the inductance value of the inductor in the time-domain lumped parameter model,, di
    k
  
  dt, represents a differential value of the sampled value of current ik at instant k, and m3and m4are coefficients specified by the operation criterion of the protection device.