TransactionsPublished under the care of the General Secretary and the Treasurer . atural complexity, distinguish the applications of analyticand graphics, and the use of space and time vectors. Errors areintroduced by the assumption of a straight saturation curve, distor-tion throughout entire circuit, saturation of field only, constant 736 RUSH MORE: REGULATION OF ALTERNATORS. air-gap, definite flux distribution, sinusoidal reactions and con-tinuous magnetic surfaces, whereby the representation of magneticfields by vectors, approximately true for induction-motor con-struction, departs widely
TransactionsPublished under the care of the General Secretary and the Treasurer . atural complexity, distinguish the applications of analyticand graphics, and the use of space and time vectors. Errors areintroduced by the assumption of a straight saturation curve, distor-tion throughout entire circuit, saturation of field only, constant 736 RUSH MORE: REGULATION OF ALTERNATORS. air-gap, definite flux distribution, sinusoidal reactions and con-tinuous magnetic surfaces, whereby the representation of magneticfields by vectors, approximately true for induction-motor con-struction, departs widely from fact with varying gap, definite polesand broken circumferences. Eefinements in calculation should notexceed accuracy of assumption. The demagnetizing effect oftransverse is the element most difficult to with the more easily obtained drop due to demagnetiz-ing turns — either by comparison of calculated values or from meas-urement on inductive loads and use of maximum and minimumstatic impedances — give results at times accurate but, on un-. f -Ka A Ao F Fig. 4.— General diagram. checked tests, uncertain. Hence the advocacy of many for theemployment of zero power-factor values only. Combined Method »• • ^- ^^ ^^- -^ In the comined method the armature reactance and the arma-ture reaction are considered separately. Various definitionsare used for these two quantities, but as regards the principle ofthe method the differences are unessential. The armature reactancemay be obtained by measurement v/ith the rotor out, by calculationfrom the short-circuit curve, by measurement when running withexcitation and with reversed sections of armature winding, or byany of the methods used for calculation. In the same way thevalue of armature reaction to be employed may be variously ob-tained. The diagram. Fig. 4, illustrates the relation of the differ-ent factors. The diagram is the same as used in the reactancemethod, the values used being di
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Keywords: ., bookcentury1900, bookdecade1900, bookidtr, booksubjectelectricity
