The Performance of the High-Current Transformer during Operation in the Wide Frequencies Range

Abstract

This paper presents the performance of the 26 kVA inductive high-current transformer (HCT) during operation in the frequencies range of transformed harmonics from 50 Hz to 5 kHz. Performed research concerns the determination of the possibility of obtaining an order of the higher harmonic of a given RMS value in its distorted output current for the required RMS value of the main component and the maximum safe instantaneous value of the input voltage equal to 400 V. The results are presented for serial, serial-parallel and parallel configurations of primary and secondary windings (9 cases). Therefore, the most favourable configuration of the primary and secondary windings sections may be chosen. The tests are performed for the transformation of the distorted current containing a fundamental component and one higher harmonic of order from the 5th changed by the 5 up to the 100th. The constant 10% higher harmonic level in relation to the main component of the distorted secondary current is set. The measurements are performed for different resistances and inductances of the secondary winding’s load resulting from the length of the connected current track.