Page 507 - Handbook of Electrical Engineering
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GENERALISED THEORY OF ELECTRICAL MACHINES      497

           primary are transformed to their equivalent two-phase variables. These transformations are detailed
           in References 3, 5 and 6 for example. The result is a transposition of the rows in the voltage-current
           equation (20.24) and the insertion of suffices 1 and 2, 1 for the primary and 2 for the secondary (as
           with static transformers). Equation (20.24) becomes:-


                                                                        
                                  Mp         0      R 2 + L 2 p   0
                      v d1                                                 i d1
                      v            0        Mp          0     R 2 + L 2 p  i
                                                                        
                           =                                                             (20.26)
                     q1                                               q1 
                              R 1 + L 1 p
                                           ω r L dq
                     0                               Mp       ω r M    i d2  
                       0        −ω r L dq  R 1 + L 1 p  −ω r M   Mp        i q2
           Where: R 1 = R a , R 2 = R k , L 1 = L a , L 2 = L k and L dq = M + L la .
                 Replace suffix ‘a’ with ‘1’, and suffices ‘kd’and ‘kq’ with ‘2’.
                 The corresponding flux linkage equation, derived from (20.21), becomes:-

                                                                          
                                                  0       M         0
                            ψ d1     M + L l1                               i d1
                                        0                  0        M       i
                                           M + L l1                       
                            ψ q1   =                                   q1          (20.27)
                           ψ d2      M         0     M + L l2    0     i d2  
                                        0        M         0
                            ψ q2                                 M + L l2   i q2
           And similarly from (20.21) and differentiating:-

                                                                             
                  pψ d1      (M + L l1 )p    0          Mp            0        i d1
                                 0                       0
                                      (M + L l1 )p               Mp       i  
                  pψ q1   =                                               q1       (20.28)
                 pψ d2       Mp           0       (M + L l2 )p     0      i d2  
                                 0          Mp           0       (M + L l2 )p
                  pψ q2                                                        i q2
           And the voltage equation (20.5) becomes:-


                                                                  
                               v d1           i d1    p   0   0   0     ψ d1
                                v     R     i      0  p  0  0     
                               q1   =      q1   +               ψ q1           (20.29)
                               v d2        i d2     0  0  p  ω   ψ d2  
                                                       0  0  −ω   p
                               v q2           i q2                      ψ q2
           Substituting (20.28) into (20.29) are rearranging the terms gives,


                                                                                        
                     R 1 + (M + L l1 )p      0               Mp                0
             v d1                                                                          i d1
             v           0         R 1 + (M + L l1 )p      0               Mp          i  
                  =
            q1                                                                        q1 
                           Mp               ωM         R 2 + (M + L l2 )p  ω(M + L l2 )    i d2
            0                                                                             
              0           −ωM               Mp           −ω(M + L l2 )  R 2 + (M + L l2 )p  i q2
                                                                                         (20.30)
           The two upper rows represent the stator and the two lower rows the rotor.
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