On- and Offline Tests
Besides factory partial discharge testing for quality assurance, field-testing becomes increasingly important for gas-insulated equipment. For the field applications UHF and acoustic detection methods complement the low frequency detection according to the IEC60270.
The main application of the AIAcompact is the acoustical detection of partial discharge in gas-insulated equipment. Conveniently, the unit provides the supply voltage of the different preamplifiers and the acoustic sensors. The instrument is light weight and battery operated. Moreover, the AIAcompact allows conducting UHF measurements when connected to embedded or external UHF sensors. The AIAcompact automatically detects the preamplifier type and selects the appropriate operation mode.
For in-depth field analysis of partial discharge activity the ICMsystem can be combined with a spectrum analyzer. Power Diagnostix has written a special software ICMspectrum to utilize and control spectrum analyzers of different vendors for partial discharge analysis (HP/Agilent 859xE, Agilent E4000, R&S FSL).
The portable ATTanalyzer is a simple and very effective tool to locate breakdown during the commissioning of GIS and GIL. Battery-operated acoustic sensors are externally mounted to the GIS and connected via fiber optic cable to the acquisition unit. In case of breakdown, the acoustic sensor transmits an optical signal to the ATTanalyzer, when it has detected the sound wave. The ATTanalyzer then displays the signals received from all sensors versus time like a logic analyzer. Following initial location of the breakdown’s origin, the acoustic sensors can be repositioned closer to the flaw to further narrow down the location.