Bulletin . t;0 + ^ ^7 (* + AO (68) iV2 With this value of an approximate value i is obtained from the sat-uration curve. By this value of i the parenthesis of equation (67) isthen filled in, and a second approximate value of obtained, whenceby means of the saturation curve, a second very close approximate valueof i is obtained. Table 4 is a convenient form for tabulation. Column 7 of Table 4gives 4> as obtained by the first approximation, and column 8 gives thecorresponding magnetizing current. Column 12 gives A <£ as obtainedwhen using i, and column 13 gives the second approximatio
Bulletin . t;0 + ^ ^7 (* + AO (68) iV2 With this value of an approximate value i is obtained from the sat-uration curve. By this value of i the parenthesis of equation (67) isthen filled in, and a second approximate value of obtained, whenceby means of the saturation curve, a second very close approximate valueof i is obtained. Table 4 is a convenient form for tabulation. Column 7 of Table 4gives 4> as obtained by the first approximation, and column 8 gives thecorresponding magnetizing current. Column 12 gives A <£ as obtainedwhen using i, and column 13 gives the second approximation of <£.Column 14 gives the corresponding value of magnetizing current, andfrom 15 the value of secondary current may be obtained. in column 7is obtained by adding A of column 6 to of the previous line incolumn 13. In Fig. 17 are plotted curves from the above case similarto those shown in Fig. 13 and in Fig. 14. Anderson-Woodrow—Series Transformers 37. MAGNETIZING CURRENT (im)Fig. 16. Current Diagram for Example 3 Fig. 16 and Fig. 17 (corresponding to examples 3 and 4), showclearly the errors introduced by the use of the series transformer withan iron core in recording transient phenomena. The steadying effectof secondary reactance is made evident by a comparison of the twocurves. The oscillograph record, shown in Fig. 18, is that of the currentthrough the secondary of the series transformer together with the cur-rent through the primary, which is the starting current of an inductive xcircuit with an electrical time constant (— ). of 10. These experi-mental curves are very similar to those as calculated from Examples 3and 4 although the constants are somewhat different. 13. Comparison of Methods of Computation for Series Transform-ers.—The agreement between the two methods of solution, namely, thecomplex quantity method and the differential equation method maybe pointed out briefly as follows. If transient terms be dropped, and
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