| 摘要 |
The partial-discharge measuring device (3) serves to detect partial discharges in a gas-insulated, metal-enclosed, high-voltage system, and exhibits an annular-gap antenna (6) arranged on the inner surface of the metal enclosure (1), a coaxial measuring cable (7) guided to a measuring instrument, and a tapering adaptor conductor (8) which connects the annular-gap antenna (6) and the coaxial measuring cable (7). The annular gap (9) of the antenna is determined by a plate-shaped electrode (10) which is inserted in an electrically insulated fashion into an opening (5), provided for a flanged attachment (4) in the metal enclosure (1), of the metal enclosure (1). The adaptor conductor (8) exhibits an inner conductor, which supports the electrode (10), and is guided onto the shielded conductor (14) of the measuring cable (7), and an outer conductor which is guided onto the shield (15) of the measuring cable (7). The flanged attachment (4) tapers in the shape of a funnel between the opening (5) and the flange (16) supported by it, and forms with its inner surface a first portion of the outer conductor of the adaptor conductor (8). Such a partial-discharge measuring device (3) is distinguished by a simple and compact design and can be produced in a cost-effective fashion. In the UHF region, which is important for an accurate measurement of partial discharges, its transfer function exhibits at frequencies between 300 MHz and 1.8 GHz a portion which is high and flat. The measuring accuracy and sensitivity of the partial-discharge measuring device (3) are therefore particularly high in this frequency region. |
