Surge Transfer in 3-Winding Transformers [includes discussion]

When an impulse wave hits a transformer winding, transient voltages are produced in all the windings. This paper discusses the voltages transferred to the terminals of the nonimpulsed windings of 3-winding transformers and autotransformers. Only two components of the transferred surge have practical significance: the electrostatic component and the electromagnetic component. Analytical expressions of the terminal voltages have been obtained for both these components for various terminal conditions of the nonimpulsed windings. Comparisons are made with tests made on an electromagnetic model of a 33,333-kva 3-winding transformer. Recommendations are made for the protection of the tertiary windings of transformers and of the apparatus connected to these windings.

[1]  P. L. Bellaschi Lightning surges transferred from one circuit to another through transformers , 1943, Electrical Engineering.

[2]  P. A. Abetti,et al.  Surge Phenomena in Large Unit-Connected Steam Turbine Generators [includes discussion] , 1952, Transactions of the American Institute of Electrical Engineers. Part III: Power Apparatus and Systems.

[3]  P. A. Abetti,et al.  Electrostatic Voltage Distribution and Transfer in 3-Winding Transformers [includes discussion] , 1954, Transactions of the American Institute of Electrical Engineers. Part III: Power Apparatus and Systems.

[4]  F. J. Maginniss,et al.  Fundamental Oscillations of Coils and Windings [includes discussion] , 1954, Transactions of the American Institute of Electrical Engineers. Part III: Power Apparatus and Systems.

[5]  K. K. Palueff,et al.  Effect, of transient voltages on power transformer design — IV , 1929, Electrical Engineering.

[6]  K. K. Palueff Effect of Transient Voltages on Power Transformer Design-III Non-Resonating Auto-Transformer , 1931, Transactions of the American Institute of Electrical Engineers.

[7]  P. A. Abetti,et al.  Transformer Models for the Determination of Transient Voltages [includes discussion] , 1953, Transactions of the American Institute of Electrical Engineers. Part III: Power Apparatus and Systems.