Patent ID: 11953635
Assignee: INSTITUTE OF GEOLOGY AND GEOPHYSICS, CHINESE ACADEMY OF SCIENCES
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 7:
8. The seismometer with high sensitivity, broadband and all-dip according to claim 7, wherein an expression of the feedback parameters is as follows:, {
  
   
    
     
      
       
        m
        ⁡
        (
        
         
          x
          ¨
         
         +
         
          w
          ¨
         
        
        )
       
       +
       kx
       +
       
        
         c
         .
        
        ⁢
        x
       
       +
       
        
         G
         s
        
        ⁢
        
         I
         s
        
       
       +
       
        
         G
         a
        
        ⁢
        
         I
         a
        
       
      
      =
      0
     
    
   
   
    
     
      
       V
       0
      
      =
      
       RI
       s
      
     
    
   
   
    
     
      
       I
       a
      
      =
      
       
        
         H
         ⁡
         (
         s
         )
        
        ⁢
        
         V
         0
        
       
       =
       
        
         (
         
          
           g
           p
          
          +
          
           
            g
            i
           
           s
          
          +
          
           sg
           d
          
         
         )
        
        ⁢
        
         V
         0
        
       
      
     
    
   
  
 

wherein, gp, gi and gd represent feedback parameters, m represents a mass of the mass block, {umlaut over (x)} represents a second derivative of a mass block position, {umlaut over (w)} represents a second derivative of surface displacement, k represents a spring coefficient, x represents the mass block position, c represents damping amount of a damper, {dot over (x)} represents a derivative of the mass block position, Gs represents an induction coil that senses displacement of the mass block, Is represents induced current generated by the seismometer due to vibration displacement, Ga represents the feedback coil that is offset in a vertical direction, Ia represents the feedback current generated by the PID feedback circuit, V0 represents a voltage value output by the seismometer, R represents resistance, H(s) represents the PID feedback circuit, and s represents the Laplace variable.