Page 104 - Mathematical Models and Algorithms for Power System Optimization
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94   Chapter 4

            model algorithm proposed in this chapter retains good convergence characteristics of the
            N-R method for high R/X ratio systems. Table 4.4 gives the iteration number and CPU
            times for the calculation results of case study 4.


                      Table 4.4 Calculation results of case 4 (iteration number and CPU time)
             R/X Ratio          2.0          3.0           4.0           5.0          10.0

             Iteration          16            16           16            16            16
             number
             CPU(s)            83.95        83.88         84.45         84.00         84.41
            The N-R method, PQ decoupled method, and optimal multiplier method are also applied in
            case study 1 and 2. The calculation results are shown in Tables 4.5 and 4.6, respectively.
            Figs. 4.1 and 4.2 give the comparison of iteration curves between the algorithm proposed in this


                         Table 4.5 Iteration results of different algorithms for case study 1
                                                                PQ Decoupled   Optimal Multiplier
             Iteration Number    SA Method       N-R Method        Method          Method
             0                  110.919563         110.919563      207.888217     110.919563
             1                  170.788623         292.803494       96.951614      98.525243
             2                   98.461830       10825.667767       23.051102      61.660412
             3                   14.046558      514897.234766   171723.786316      39.123108
             4                   34.560182     1055424.734328   510465.097463      34.989980
             5                   11.420726                     1103428.603472      28.075667
             6                   26.424113                                         25.065202
             7                    9.852771                                         26.857728
             8                   17.705175                                         27.339888
             9                   10.316829                                         27.470294
             10                   9.852771                                         27.506939
             11                   8.625845                                         27.517712
             12                   2.375822                                         27.521011
             13                  11.218251                                         27.521053
             14                   2.355714                                         27.522389
             15                   4.741337                                         27.522498
             16                   5.765086                                         27.522537
             17                   9.816529                                         27.522549
             18                   5.592344                                         27.522553
             19                   4.660007                                         27.522556
             20                   2.435602                                         30.346724
             21                   2.517654                                         30.327643
             22                   4.115390                                         30.335300
             23                   1.342672                                         30.342986
             24                   2.261429                                         30.347456
             25                   0.716623                                         30.349673
             26                   0.731194                                         30.350696
             27                   0.714000                                         30.351151
             28                   0.064956                                         30.351348
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