Patent ID: 11927379
Assignee: XI'AN JIAOTONG UNIVERSITY
Field: Thermal processes and apparatus (Mechanical engineering)
Classification: CPC F  Y | IPC F

Claim 4:
5. The control method of claim 4, wherein
during normal heating, the waterway two-way regulating valve (4) automatically regulates its opening degree through an adaptive fuzzy PID controller; the adaptive fuzzy PID controller takes a temperature difference ΔT between inlet water and outlet water of the CO2 gas cooler (12) and a change rate dΔT/dt of the temperature difference as input, and utilizes a fuzzy control rule to modify PID parameters on line so as to meet a requirement of self-tuning the PID parameters; and the PID parameters are fuzzy self-tuned to find a fuzzy relation among parameters kP, kI, kD and ΔT, dΔT/dt of PID;
during normal heating, the opening degree d(tk) of the waterway two-way regulating valve (4) is calculated according to the following formula:, d
   ⁡
   (
   
    t
    k
   
   )
  
  =
  
   
    
     C
     1
    
    ⁢
    
     k
     P
    
    ⁢
    Δ
    ⁢
    
     T
     ⁡
     (
     
      t
      k
     
     )
    
   
   +
   
    
     C
     2
    
    ⁢
    
     k
     I
    
    ⁢
    
     
      
       ∑
       k
      
      
       i
       =
       0
      
     
     
      Δ
      ⁢
      
       T
       ⁡
       (
       
        t
        i
       
       )
      
     
    
   
   +
   
    
     C
     3
    
    ⁢
    
     
      k
      D
     
     [
     
      
       Δ
       ⁢
       
        T
        ⁡
        (
        
         t
         k
        
        )
       
      
      -
      
       Δ
       ⁢
       
        T
        ⁡
        (
        
         t
         
          k
          -
          1
         
        
        )
       
      
     
     ]
    
   
  
 

where k denotes a number of operations; ΔT denotes the temperature difference between the outlet water and refrigerant of the CO2 gas cooler; C1-C3 denote weight coefficients; and kP, kI and kD denote the PID parameters.