Page 476 - Mathematical Techniques of Fractional Order Systems
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462  Mathematical Techniques of Fractional Order Systems


               We chose D as

                                               1
                                        k 1
                                   D 5                               ð15:30Þ
                                         1  ðk 2 2 αÞ
               Matrix D satisfies the condition 15.19 for k 1 ; k 2 . 0. Therefore, multi-
            switching synchronization is achieved.
            15.4.5 Case 5

            For Switch 5 defined by Eq. (15.15), the time derivative of the errors is
            given by
                         q
                       d e 51                        3
                            5 y 2 1 β x 1 1 βx 2 1 βx 3 2 βx 1 u 1 ðtÞ
                                   1
                                                     1
                        dt q
                                                         3
                            5 e 51 1 x 1 1 β x 1 1 βx 2 1 βx 3 2 βx 1 u 1 ðtÞ
                                        1
                                                         1
                            5 e 51 1 f 51 ðx; yÞ 1 u 1
            where f 51 is defined as:
                        f 51 5 x 1 1 β x 1 1 β x 2 1 β x 3 2 β x 3
                                  1
                                              3
                                        2
                                                    4 1
                       q
                      d e 52     3
                          5 y 1 2 y 2 αy 2 1 fcosωt 1 u 2 ðtÞ 2 x 2
                                 1
                       dt q
                                      3
                          5 e 51 2 x 3 2 y 2 αx 1 1 fcosωt 2 x 2 2 αe 52 1 u 2
                                      1
            where f 52 are nonlinear terms in e 11 and e 12 given as
                                         3
                               f 52 5 x 3 2 y 2 αx 1 1 fcosωt 2 x 2
                                         1
                              q
                             d e 52
                                  5 e 51 2 αe 52 1 f 52 ðx; yÞ 1 u 2
                              dt q
            Theorem 5: If the control function u 1 ðtÞ and u 2 ðtÞ are chosen such that
                             u 1 ðtÞ 52 f 51 ðx; yÞ 1 k 1 e 51 1 e 52
                                                                     ð15:31Þ
                                 52 f 52 ðx; yÞ 1 e 51 1 ðk 2 2 αÞe 52
            then the drive system 15.9 will achieve multiswitching synchronization with
            the response system 15.10

            Proof: The method of active control is employed to prove theorem 5.
               In order to eliminate the nonlinear term in e 1 and e 2 , we define the active
            control input u 1 ðtÞ and u 2 ðtÞ as

                                 u 1 ðtÞ 52 f 51 ðx; yÞ 1 V 51 ðtÞ
                                 u 2 ðtÞ 52 f 52 ðx; yÞ 1 V 52 ðtÞ
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