SOME OBSERVATIONS ON THE PERFORMANCE OF MODERN WIDEBAND CURRENT TRANSFORMERS IN PULSE CURRENT MEASUREMENT APPLICATIONS

B. V. Cordingley, Lilco Ltd, Livingston, U.K.
D. J. Chamund, Dynex Semiconductor, Lincoln, U.K


In this paper an analysis of the performance on both internally- and externally-terminated current transformers is presented. Factors limiting the I-t, droop, peak pulse current, frequency response and mean dc current performance of these instruments is discussed and trade-offs examined. Experimental results which demonstrate the behaviour of inexpensive ring-type designs over a broad spectrum of frequencies are examined and compared with those achieved with internally-terminated structures. It is shown that some externally-terminated ring-type designs can produce a good and versatile performance in the measurement of pulse currents with frequency components below 0.1 Hertz and to several hundred kilohertz. Internally-terminated designs extend the performance by two to three decades of frequency for applications where high-frequency harmonics are to be measured accurately.

Presenting Author : Cordingley B.