Patent ID: 11906557
Assignee: SCHWEITZER ENGINEERING LABORATORIES, INC.
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 4:
5. The IED of claim 4, wherein the instructions, when executed by the processing circuitry, are configured to cause the processing circuitry to perform operations comprising:
generating a cosine signal and a sine signal from the cosine values and the sine values; and
multiplying the cosine signal and the sine signal with the input signal to obtain the intermediate signal such that:, X
   m
  
  (
  
   
    
     
      cos
      ⁢
        
      
       (
       ϕ
       )
      
     
     +
     
      j
      ⁢
        
      sin
      ⁢
        
      
       (
       ϕ
       )
      
     
    
    2
   
   +
   
    
     
      cos
      ⁢
        
      
       (
       
        
         4
         ⁢
         
          π
          ⁢
          ft
         
        
        +
        ϕ
       
       )
      
     
     -
     
      j
      ⁢
        
      sin
      ⁢
        
      
       (
       
        
         4
         ⁢
         
          π
          ⁢
          ft
         
        
        +
        ϕ
       
       )
      
     
    
    2
   
  
  )
 

where Xm is an amplitude of the input signal, f is a frequency of the input signal, t is a current time, and ϕ is the phase, wherein the adjustable length rounded-corner boxcar filter reduces or removes an alternating current (AC) component.