A Method of Calculating the Voltage Distribution of Cascade-Connected Testing Transrormers

For design purposes cascadedtesting transformer circuits can be reduced to equivalent inductance and capacitance networks by properly combining the circuit elements. After establishing the circuit conditions, the initial surge voltage to ground at any point in the circuit and at any time can be calculated, thereby fixing an insulation design level for all units of the cascade set. The inductance and capacitance elements of the cascaded windings involved are identified and are reduced to an equivalent twoor three-mesh network, and the method for calculating the surge distribution across each unit is developed. Formulas, curves, and diagrams for the various steps are included and oscillograms of test waves are shown to establish the accuracy and validity of the method.