The Triple-Harmonic Equivalent Circuit in Three-Phase Power Transformer Banks
- 1 March 1933
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in Transactions of the American Institute of Electrical Engineers
- Vol. 52 (1) , 64-71
- https://doi.org/10.1109/T-AIEE.1933.5056253
Abstract
The importance of triple-harmonic voltages and currents in electrical power systems is generally recognized by engineers associated with the power and telephone industries. It is desirable to have some convenient method of representation and calculation of the triple-frequency effects in three-phase power systems. The path of the third-harmonic current is different fromn that of the fundamental current and for this reason the circuit can be considered as separate and, distinct. The characteristics of the triplefrequency circuit as determined by laboratory experiment are given in this paper. Methods of measurement of the required quantities for accurate solution of the triple-frequency circuit are described. The results of an experimental investigation of the equivalent triple-frequency circuit as proposed by H. S. Osborne in 1915 are set forth. A typical simple three-phase power network has been set up and the measured currents compared with computed values. Oscillograms are presented of voltages and currents with typical transformer connections demonstrating the principles of operation of the circuit both for normal and abnormal excitation conditions. The effects of various types of connected loads are discussed, with particular attention given to the condition of triple-frequency resonance. It is shown that triple-frequency resonance occurs when the external capacitive reactance of the circuit is equal to the triple-frequency no-load impedance of the transformer. Resonance produces large triple-frequency currents and serious distortion of the line-to-neutral voltage of the system.Keywords
This publication has 15 references indexed in Scilit:
- Residual Voltages and Currents in Power SystemsTransactions of the American Institute of Electrical Engineers, 1929
- Circulation of Harmonics in Transformer CircuitsTransactions of the American Institute of Electrical Engineers, 1926
- Separate Leakage Reactance of Transformer WindingsTransactions of the American Institute of Electrical Engineers, 1925
- Transformer Harmonics and Their DistributionTransactions of the American Institute of Electrical Engineers, 1925
- Triple harmonics in transformersJournal of the American Institute of Electrical Engineers, 1922
- Phenomena Accompanying Transmission with Some Types of Star Transformer Connections-IITransactions of the American Institute of Electrical Engineers, 1917
- The Effect of Delta and Star Connections upon Transformer Wave FormsTransactions of the American Institute of Electrical Engineers, 1914
- Harmonic Voltages and Currents in Y- and Delta-Connected TransformersTransactions of the American Institute of Electrical Engineers, 1914
- Influence of Transformer Connections on OperationTransactions of the American Institute of Electrical Engineers, 1914
- Observation of Harmonics in Current and in Voltage Wave Shapes of TransformersTransactions of the American Institute of Electrical Engineers, 1910