摘要 |
<p>A capacitor component (18, 22) is adapted for capacitive coupling to an electrical power apparatus (15) in which a PD is suspected, such as a shielded power cable (15); and an impedance transformance device (102) has an input side connected directly to the capacitor component (18, 22). Together the two components are used as a sensor (100) to pick up and convey PD signals to a PD signal-analyzing system (D). Although the two components inherently form a classic high-pass RC filter, in accordance with the invention the input impedance at the capacitor side is much greater than the output impedance at the signal-analyzing system side. The effect is to pass much more of the lower frequency components of the PD signal for analysis by the PD signal-analyzing system (D) than if the transformance device (102) were not included.</p> |