SynopsisMethods of calibrating circuits for measuring partial discharges and radio-interference (r.i.) voltages are discussed. It is shown that discharge-measuring circuits, whether using a peak-measuring discharge detector or an r.i. meter, are best calibrated by applying a charge-quantity pulse calibrator of known repetition frequency in parallel with the test sample. The calibration of circuits for measuring r.i. voltages is more complex, and certain anomalies arise when a sine-wave signal generator is used to calibrate the circuit in terms of voltage input.It is established that, for a pulse-repetition rate of lOOpulse/s, it is possible to relate the results obtained from a conventional peak-reading discharge detector to those from a quasipeak r.i. meter; e.g. for a meter having 60 Q input impedance and a bandwidth of 9kHz, the relationship is: 1 JUV is equivalent to 2-6pC. At repetition rates other than lOOpulse/s, it is shown that theoretically the maximum error involved by using the above relationship is 6dB between 25-2000pulse/s. Practical measurements confirm that the error does not exceed ±6dB over a wide range of pulse sizes and repetition frequencies.Comparative measurements have shown that the conventional r.i. meter is approximately an order of magnitude less sensitive than a tuned-circuit discharge detector. Methods of improving the sensitivity of the former are described.It is concluded that for many applications either a discharge detector or an r.i. meter will enable both discharge magnitude and r.i. voltage to be determined with sufficient accuracy, considering the erratic behaviour of pulses in practice.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.