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Load Optimization for Power Network 137

               5.5.1.3 Result of 5-bus system for state 1
               According to the linear programming model of optimizing 5-bus system LC, use the linear
               programming STYRP1.10 software package developed in China to calculate LCO for Status 1.

               STYRP1.10 solves the linear programming problem by using a modified simplex method. It
               only requires a general form of linear programming, and the program will automatically process
               range and bound constraints. The specific input data requirements and formats are described in
               the following section:

               (1) The objective function, equality constraints, and inequality constraints are written into the
                    coefficient A matrix (as variable C in the program), which designates the location of
                    objective function by IOB¼1; the right hand side constraint variable is D; set the right
                    hand side constraint of the objective function to 0.
               (2) The type of equation is represented with ITYPE ( 1 indicates less than or equal to, or
                    maximizing; 1 indicates more than or equal to, or minimizing; 0 indicates equal to).
               (3) The bound constraints of linear programming are represented with variable IBD
                    (boundary index) and BD (boundary value): if the nth variable has bound constraints, then
                    n indicates upper bound constraint and –n indicates lower bound constraint; BD is the
                    specific upper and lower boundary values of each variable.
                    Thus, according to the expressions for two linear programming models of state 1 of 5-bus
                    system discussed previously, the input variables A, D, ITYPE, IBD, and BD from the
                    STYRP1.10 solution are expressed as follows:
               (4) Input variable coefficient for the linear programming software package:


                                        2                                  3
                                             1        1      1     0     0
                                        6    1        1      1     1     1  7
                                        6                                  7
                                        6  0:3344 0:3282     0   0:3282 0  7
                                        6                                  7
                                    A ¼  0:3365  0:6698 0        0:6698 0 ,
                                                                           7
                                        6
                                        6                                  7
                                        6   0:6656  0:3313 0  0:3313 0     7
                                        6                                  7
                                        4    0        0      0     1     0  5
                                             1        1      1      1    0
                                   2    3      2         3
                                     1              0
                                                    3:3
                                     0 7
                                   6           6         7
                                   6    7      6         7
                                      1           1:1843
                                   6    7      6         7         2   3        2    3
                                   6    7      6         7          1             1:2
                                      1           1:9656
                                   6    7      6         7
                                                                    2             0:6
                                   6    7      6         7         6   7        6    7
                                   6  1  7     6  1:9776  7        6   7        6    7
                                   6    7      6         7         6 3  7       6 1:5  7
                                   6  1  7     6  1:5000  7        6   7        6    7
                           ITYPE ¼  6   7 , D ¼  6       7 , IBD ¼  4 , BD ¼ 0:3     7
                                                                   6
                                                                                6
                                                                       7
                                   6  1  7     6  6:3000  7        6   7        6    7
                                   6    7      6         7         6 4  7       6 1:4  7
                                   6 1  7      6  0:7757  7        6   7        6    7
                                   6    7      6         7         4  5  5      4 2:0  5
                                   6 1  7      6  0:3544  7
                                   6    7      6         7          5             3:0
                                   6 1  7      6  0:0176  7
                                   6    7      6         7
                                   4 1  5      4  1:5000  5
                                     1            0:3000
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