Electromagnetic phenomena in high-voltage testing equipment

The paper discusses a number of electromagnetic phenomena which may be encountered in the operation of high-voltage testing equipment. Although secondary in magnitude these effects are not secondary in importance, since they may vitiate the accuracy of important tests and lead to the loss of much time and money. Theoretical deductions are throughout supported by actual experimental results. Part 1 deals with wave-form distortion in the usual single-phase normal-frequency transformer equipment. The factors considered include core saturation, capacitance loading, and induction-regulator and alternator characteristics. Information is also given as to the effect of wave-form on breakdown voltage and dielectric losses. Part 2 deals with transient phenomena in testing-transformer circuits. The production of over-voltages by switching and by discharges in the load is discussed in detail. Oscillations in rectifier circuits are also considered. Part 3 deals with wave-form distortion in the impulse generator. Special attention is given to the superimposed oscillations introduced by load capacitance and by measuring circuits. The theory of the oscillation transformer is developed as a special case of the impulse generator, and test results are given for an actual equipment.