Page 234 - Handbook of Electrical Engineering
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218    HANDBOOK OF ELECTRICAL ENGINEERING

              The charging current at the sending end I cs is,

                                                  19456.7
                                           V s
                                     I cs =    =           =+j18.337 amps
                                           2X c  −j1061.04
              Deduct I cs from I s to obtain I sr ,

                                     I sr = I s − I cs = 317.85 − j80.713 − j18.337
                                        = 317.85 − j99.05

              The volt-drop V sr in the series impedance is,

                              V sr = I sr (R + jX 1 ) = (317.85 − j99.05)(2.5 + j2.75)
                                               = 794.63 + j874.09 − j247.625 + 272.39

                                               = 1067.02 + j626.46 volts/phase

              Hence the voltage received at the load is,

                                          V r = V s − V sr
                                            = 19456.7 − 1067.02 − j626.46
                                            = 18389.68 − j626.46

                                         |V r |= 18400.35 volts/phase

              The total actual volt-drop

                                            |V s |− |V r |
                                       V =           × 100
                                               |V s |
                                            (19456.7 − 18400.35)100
                                         =                        = 5.429%
                                                   19456.7

              The receiving end volt-drop with respect to the nominal system voltage is  V n ,
                                            |V n |− |V r |
                                      V n =           × 100
                                               |V n |
                                            (19052.6 − 18400.35)100
                                          =                       = 3.423%
                                                   19052.6
              c) Neglecting the shunt capacitive reactance.
                    The method of 9.4.3.1 can be used for a long cable to compare the results and accuracy
              obtained. The current in the load based on the nominal system voltage is I,

                                             S L × 10 6
                                         I =  √      = 349.91 amps/phase
                                                3V n
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