Description
The monitoring system will employ the Prysmian smart PD sensors at all measurement points. These are active electromagnetic sensors capable of sensing the PD pulses without the need of a direct connection to the component under test, unlike traditional HFCT or capacitive couplers. Each sensor is capable of recovering the AC voltage phase, so to provide a synchronisation signal for acquired PC. This avoids the need of additional CT or Rogowski coil. Each device also include temperature and current measurement sensors that can be used to track cable loading and environmental conditions.
A smart PD sensor is shown in Fig. 4a. It is has a small flat silicon package that can be sticked on (or near) the component under test as a patch. The sensor includes sensing elements and amplifiers, and it is connected to the Pry-Cam Grids unit by a standard ISO/IEC 11801/EN 50173 twisted pair cable. The length of this cable should be kept shorter than about 15m for optimal performances. The use of wide band sensors and active amplification allows to achieve a very good signal to noise performances.
Data sheet
