Page 288 - Mathematical Models and Algorithms for Power System Optimization
P. 288

280 Chapter 7

                                       1      A          B         C     D
                                GZðÞ ¼ ¼           +          +         +
                                       S  0:53S +1   45:27S +1  0:5S +1   S

                                        1
                                A ¼ GS ðÞ ð 0:53S +1Þ    1  ¼ 2:68775
                                        S
                                                    S¼
                                                       0:53

                                        1
                                B ¼ GSðÞ ð 45:27S +1Þ     1   ¼ 42:1123
                                        S
                                                     S¼
                                                        45:27

                                        1
                                C ¼ GSðÞ ð 0:5S +1Þ    1  ¼ 2:5
                                        S
                                                   S¼
                                                      0:5

                                        1
                                D ¼ GSðÞ   S    ¼ 1
                                        S
                                             S¼0
            Substitute them into Eq. (7.98) to get:

                              5:0679         0:93025       4:999999       1           1
                   GZ ðÞ ¼              +              +             +          1 Z
                                    Z
                                                   Z
                                                                 Z
                           1 e  1=0:53  1  1 e 1=45:27  1  1 e 1=0:53  1  1 Z  1
                                                  E
                        ¼
                                                                         1
                                       1
                                                         ð
                          ð 1 0:15156Z Þ 1 0:97815Zð   1 Þ 1 0:1353353Z Þ
            where

                                                1            1
                             E ¼ 5:0697 1 e 0:5Z   1   1 e 0:527Z  1  1 Z  1

                                                 1            1
                                 0:93024 1 e 0:53Z   1   1 e 0:5Z  1  1 Z  1

                                                 1             1
                                +4:99997 1 e 0:53Z  1    1 e 45:27Z  1  1 Z  1

                                         1             1             1
                                +1 e 0:53Z   1   1 e 45:27Z  1  1 e 0:5Z  1
                              ¼ 0:0020285Z    1  +0:0895481Z  2   0:0714933Z  3
            Finally

                                    0:0020285Z   1  +0:0895481Z  2   0:714933Z  3
                            GZðÞ ¼
                                          1 1:265Z   1  +0:3Z  2   0:02Z  3



            (2) Solve the transfer function by the State equation method.
                 First, transform G(S) into a state equation (and in reference to the hydro unit model)
   283   284   285   286   287   288   289   290   291   292   293