Patent ID: 11909218
Assignee: nan
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A method for managing a fast frequency response (FFR) of a distribution-level integrated electric-gas system (D-IEGS), the method comprising:
operating a D-IEGS wherein:
an active power disturbance uncertainty is modeled as:

ΔPdis,te=zteuΔPdis,te−−ztedΔPdis,te+, ∀te

{zteu, zted∈{0,1}, zteu+zted≤1},  (11)

wherein te represents a scheduling period of a power system; ΔPdis,te is an aggregated active power disturbance; ΔPdis,te− is a negative active power disturbance; ΔPdist,te+ is a positive active power disturbance; and zteu and zted are binary variables, and represent a disturbance type,

FFR incremental outputs can be described by:

{tilde over (P)}gte,k=Pgte+(zgteu−zgted)ΔPte,kg, 1≤k≤N

{zgteu, zgted∈{0,1}, zgteu+zgted≤1}  (12)

{tilde over (P)}pte,k=Ppte−(zpteu−zpted)ΔPte,kp, 1≤k≤N

{zpteu, zpted∈{0,1}, zpteu+zpted≤1}  (13)

wherein ΔPte,kg and ΔPte,kp denote the incremental active power outputs/consumption of gas-fired turbines (GTs) and power-to-gas (P2G) units during an FFR regulation process; k is an index for frequency dynamics difference time step and N is a total number of time steps; zgteu and zgted are binary variables, representing an uncertainty of GT active power outputs; zpteu and zpted are binary variables, representing an uncertainty of P2G active power consumption; Pgte is a steady-state active power outputs of GT; Ppte is a steady-state active power consumption of P2G; and {tilde over (P)}gte,k and {tilde over (P)}pte,k are an uncertain active power outputs of GT and an uncertain active power consumption of P2G, respectively, and

a gas load uncertainty can be quantified by:, M
       ~
      
      
       g
       ⁢
       
        τ
        g
       
      
     
     =
     
      {
      
       
        
         
          
           
            
             
              P
              ~
             
             
              
               gt
               e
              
              ,
              k
             
            
            /
            
             η
             g
            
           
           ,
           
            τ
            ∈
            
             [
             
              1
              ,
              N
             
             ]
            
           
          
         
        
        
         
          
           
            
             
              P
              
               gt
               e
              
             
             /
             
              η
              g
             
            
            ,
            
             τ
             ∈
             
              (
              
               N
               ,
               
                N
                g
               
              
             
            
           
           ]
          
         
        
       
       ,
       
        
         
          M
          ~
         
         
          p
          ⁢
          
           τ
           g
          
         
        
        =
        
         {
         
          
           
            
             
              
               
                P
                ~
               
               
                
                 pt
                 e
                
                ,
                k
               
              
              ⁢
              
               η
               p
              
             
             ,
             
              τ
              ∈
              
               [
               
                1
                ,
                N
               
               ]
              
             
            
           
          
          
           
            
             
              
               
                P
                
                 pt
                 e
                
               
               ⁢
               
                η
                p
               
              
              ,
              
               τ
               ∈
               
                (
                
                 N
                 ,
                 
                  N
                  g
                 
                
               
              
             
             ]
            
           
          
         
        
       
      
     
    
   
   
    
     (
     14
     )
    
   
  
 

wherein {tilde over (M)}gτg and {tilde over (M)}pτg represent a gas consumption uncertainty of the GTs and a gas generation uncertainty of the P2G units; {tilde over (P)}gte,k, {tilde over (P)}pte,k, Pgte, Ppte, and N are as defined in the formulas (12) and (13); ηg is an energy conversion efficiency of GT; ηp is an energy conversion efficiency of P2G; τ is a time resolution of a gas flow model; and Ng is a number of gas flow time difference steps in one power system scheduling period;

initializing an energy management main problem of the D-IEGS as follows:, min
       x
      
      
       c
       T
      
      ⁢
      x
     
     +
     
      
       b
       T
      
      ⁢
      
       y
       ˜
      
     
    
   
   
    
     (
     15
     )
    
   
  
 

 
  
   
    s
    .
    t
    .
       
    Ax
   
   +
   
    B
    ⁢
    
     y
     ˜
    
   
  
  ≤
  d
 

 
  
   ||
   
    
     
      F
      i
     
     ⁢
     x
    
    +
    
     g
     i
    
   
   
    ||
    2
   
   
    ≤
    
     
      
       K
       i
       T
      
      ⁢
      x
     
     +
     
      f
      i
     
    
   
  
  ,
  
   i
   ∈
   ℒ
  
 

wherein {tilde over (y)} denotes an FFR reserve vector; x is a vector of all the remaining decision variables; A, B, Fi, Ki, d, gi, fi, c and b are constant coefficient matrices or vectors; i and  are an index and a set of second-order cone (SOC) constraints;

solving a feasibility-check sub-problem to test the operation constraint violation against a worst-case uncertainty, wherein the feasibility-check sub-problem is as follows:, s
     .
     t
     .
        
     
      
       
        
         
          max
          z
         
         
          min
          
           
            s
            ≥
            0
           
           ,
           x
          
         
           
         
          1
          T
         
         ⁢
         s
        
       
      
      
       
        
         
          Ex
          +
          
           G
           ⁢
           s
          
          +
          
           H
           ⁢
           z
          
         
         ≤
         
          h
          -
          
           C
           ⁢
           
            
             y
             ˜
            
            *
           
          
         
        
       
      
      
       
        
         
          ||
          
           
            
             F
             i
            
            ⁢
            x
           
           +
           
            g
            i
           
          
          
           ||
           2
          
          
           ≤
           
            
             
              K
              i
              T
             
             ⁢
             x
            
            +
            
             f
             i
            
           
          
         
         ,
         
          i
          ∈
          ℒ
         
        
       
      
     
    
   
   
    
     (
     16
     )
    
   
  
 

where z denotes boolean uncertainty variables; s denotes relax variables; {tilde over (y)}* is a solution of a master problem; x, Fi, Ki, gi, fi are as defined in the formula (15); and E, G, H, h, C are constant coefficient matrices or vectors, and if an objective value of (16) is positive, it indicates the energy management strategy of the D-IEGS is not robust to all the possible frequency disturbances and the following constraints is added to the main problem:, E
       ⁢
       
        x
        j
       
      
      +
      
       C
       ⁢
       
        y
        ˜
       
      
      +
      
       H
       ⁢
       
        z
        
         j
         *
        
       
      
     
     ≤
     h
    
   
   
    
     (
     17
     )
    
   
  
 

 
  
   ||
   
    
     
      F
      i
     
     ⁢
     
      x
      j
     
    
    +
    
     g
     i
    
   
   
    ||
    2
   
   
    ≤
    
     
      
       K
       i
       T
      
      ⁢
      
       x
       j
      
     
     +
     
      f
      i
     
    
   
  
  ,
  
   i
   ∈
   ℒ
  
 

wherein j is an iteration index; zj* represents an identified worst-case uncertainty in jth iteration; xj is a new variable vector added to the main problem; and remaining variables are as defined in the formulas (15) and (16), and solve the main problem and the feasibility-check sub-problem again; and

adjusting power generation of GTs and P2G units based on the new variables to change node gas injection and gas distribution network (GDN).