Page 287 - Mathematical Models and Algorithms for Power System Optimization
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Optimization Method for Load Frequency Feed Forward Control 279

               Substitute it into Eq. (7.77):

                                               2                  3
                                                  lnλ 1
                                                                  7  1
                                                       lnλ 2 ln λ 1 5T
                                               6              0
                                                               ðÞ
                                          A ¼ T4
                                                              lnλ 2
                                              2            3
                                                1  10
                                              6            7
                                            ¼ 4  4  30 5
                                                10  2
               (2) Using the logarithmic matrix method to obtain A:

                                            2                          3
                                               1     1          0
                                        A ¼  4  4    3          0      5
                                               13 10     8   2+3 10   9


               (3) Using the successive approximation method to obtain A.
                    After obtaining ϕ(0.01), use the Eq. (7.106) to solve A:

                                              2                      3
                                                0:995    1       0
                                           A ¼  4  4   3:005     0   5
                                                  1    0:006  2:001




               7.8.6.3 Results of Example 3
               If the transfer function for hydro turbine governor and prime mover is known:

                                                     ð 5S +1Þ 1 SÞ
                                                            ð
                                     GSðÞ ¼
                                                      ð
                                                                   ð
                                            ð 0:53S 1Þ 45:2698S +1Þ 0:5S +1Þ
               To be solved is the difference transfer function with difference time of T¼1s.
               (1) Solve the transfer function by the Direct Z transform method.
                    With Eq. (7.108):
                                                                 TS
                                                           ð 1 e   Þ
                                             GZðÞ ¼ ZG SðÞ
                                                              S
                                   1
               First, expand GZðÞ ¼ into the form of partial fractions
                                   S
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