HYDROCAL BPD is a modular online monitoring system for high voltage bushings. It supports the measurement of voltage and phase angle on the test tap to derive tanδ/PF, bushing capacitance.
HYDROCAL BPD can be combined with other HYDROCAL models, preferably HYDROCAL genX, in order to set up a comprehensive monitoring system. As per CIGR… Working Group A2.37 bushings resp. the lead exit represents the 2nd largest group of transformer failure locations (approx. 25%) after the windings (43%) and before the tap changers (23%). Therefore, bushing monitoring can help to reduce those failures.
 
HYDROCAL BPD combined with online DGA performed by the HYDROCAL product family provides the ideal overall transformer monitoring solution.
 
The measurement of voltage and phase angle on the test tap of high voltage bushings allows to compare tanδ/PF with factory test results for analysing deterioration of the bushings.