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               In the following, we will design the decentralized LFC law under the communication network. Similar to [23] ,
               a PI controller is used in this paper:
                                                                 ¹
                                                (  ) = −                  (  ) −                    (  ).  (8)
               Therefore, dynamic model of the scheduled power systems under the decentralized LFC Equation (8) and
               imperfect network environments can be formalized as
                                           (
                                            ¤   (  ) =     (  ) −      ˆ  (      ) +     (  )
                                                                                                       (9)
                                              (  ) =     (  ),    ∈ [      ,      +1 ),

                             
                           Í
               where   (  ) =              (  ) =     (  ),    = [   1 , · · · ,       ],       = [        ,         ].
                            =1
               2.2. Impulsive model and study objective
               From Equation (5), one can obtain that
                                               (
                                                          (      ) −         (     +1 ),    =      
                                            (     +1 ) =                                              (10)
                                                        [  (      ) −   (     +1 )] +       (      ),    ≠      
               Define an artificial delay   (  ) =    −      , from which one arrives at

                                                                  ≤       , ¤(  ) = 1.                (11)
                                                                          
                                      0 ≤           ≤   (  ) ≤      +1 −       +         +1
               From Equation (5) and Equation (9), the impulsive power system model can be

                                                                   
                                                                 Õ
                                    ¤   (  ) =     (  ) −         (   −   (  )) −                      (  ) +     (  ).  (12)
                                                                 =1,  ≠     
               ForsystemEquation(12), the initialconditionof   (  ) on [−      , 0] issupplementedas   (  ) =   (  ),    ∈ [−      , 0],
               with   (0) =    0, where   (  ) is a continuous function on [−      , 0].


               Using scheduling scheme Equation (6) and Equation (7), this paper is to design the decentralized controller
               Equation (8) such that system Equation (12) is exponentially stable with a prescribed    ∞ performance   .



               3. MAIN RESULTS
               In the following, we first derive sufficient criteria under scheduling scheme Equation (6) and Equation (7) to
               ensure the exponential stability of system Equation (12) with a prescribed    ∞ performance. Then, criteria are
               proposed to design decentralized controllers under multi-channel transmission.


               3.1. Stability analysis under the TOD scheduling scheme Eqution (6)
               Construct Lyapunov-Krasovskii functional candidate:
                                                    
                                                  Õ     
                                             (  ) =     (  )            (  ) + Π(  ) +       ,        (13)
                                                        
                                                    =1
               where    > 0,       > 0,   > 0,       > 0,    > 0,    > 0,    = 1, · · · ,   ,    ∈ [      ,      +1 ),

                                  ¹    
                              Õ              
 p       
 2
                                             
             ¤  (  )
     ,
                               =             2  (  −  )
                                =1       
                              ¹                                     ¹      ¹    
                                                                                   ¤    (  )   ¤(  )        .
                        Π(  ) =       2  (  −  )                                2  (  −  )       
                                            (  )    (  )     +    (  )    (  ) +      
                                 −                                     −         
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