Page 136 - Handbook of Electrical Engineering
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118    HANDBOOK OF ELECTRICAL ENGINEERING

              requires stabilising with a ‘deceleration’ factor. Equation (5.7) for slip = 1 can be expanded to yield
              the following equation,

                                                                  j(D 1 E 1 − C 1 F 1 )
                                                    C 1 E 1 + D 1 F 1
                               Z 231 = R 231 + jX 231 =         +                             (5.9)
                                                        G 1             G 1
              Similarly (5.8) for slip = s can be expanded to yield the following equation,

                                                                  j(D 0 E 0 − C 0 F 0 )
                                                    C 0 E 0 + D 0 F 0
                               Z 230 = R 230 + jX 230 =         +                            (5.10)
                                                        G 0             G 0
              From (5.9) a new value of R 22 can be found as R 22N ,

                                                G 1 R 231 − D 1 F 1  X 22 X 33
                                         R 22N =              +                              (5.11)
                                                    E 1 R 33      R 33
              Also from (5.9) a new value of X 22 can found be as X 22N ,


                                                G 1 X 231 + C 1 F 1  R 22 X 33
                                         X 22N =              −                              (5.12)
                                                    E 1 R 33      R 33
              From (5.10) a new value of R 33 can be found as R 33N ,

                                                G 0 R 230 − D 0 F 0  X 22 X 33
                                         R 33N =              +                              (5.11)
                                                    2              2
                                                   U E 0 R 22    U R 22
              Also from (5.10) a new value of X 33 can be found as X 33N ,


                                                G 0 X 230 + C 0 F 0  X 22 R 33
                                         X 33N =              −                              (5.12)
                                                   UE 0 R 22      R 22
              Where    U = 1/slip = 1/s
                      C 1 = R 22 R 33 − X 22 X 33
                      D 1 = R 22 X 33 + X 22 R 33
                      E 1 = R 22 + R 33
                      F 1 = X 22 + X 33
                             2     2
                      G 1 = E 1 + F 1
                          2
              and  C 0 = U R 22 R 33 − X 22 X 33
                   D 0 = UR 22 X 33 + X 22 R 33
                   E 0 = U(R 22 + R 33 )
                    F 0 = X 22 + X 33
                          2  2     2
                   G 0 = U E 0 + F 0
                    The calculation process is simple and convergent provided some deceleration ‘k’ is applied.
              An initial guess is required for R 22 , X 22 , R 33 and X 33 , which may require a little trial and error
              experimentation to find suitable values. These values are used in the equations to yield a new set of
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