PowerPAC^TM is a Technology Package for detecting and locating partial discharge in power transformers by utilizing Acoustic Emission.  Developed under an EPRI sponsored Tailored Collaboration (Project I.QD. No. 051481), this package is designed to provide on-line monitoring of Power Transformers for the detection, location and assessment of electrical and thermal faults. This monitoring follows a procedure that was introduced in the Tailored Collaboration and refined throughout two Phases of program development.  Transformers are instrumented with AE sensors covering both the tank and the LTC compartment (if one is present).  In addition,  other sensors (used to monitor pump current, fan current, load current, tank wall temperature and LTC compartment wall temperature) are used to collect data for comparison with the AE data during post test data analysis.

Data is collected over a period of 24 hours in order to observe the effects of a complete load cycle.  Results are presented showing the location (in three dimensions) and types of faults. A grading system is used to grade each fault and to provide an overall grading of the transformer to be used for maintenance or operations planning. The system in based on the Physical Acoustics Corporation (PAC) model DiSP, digital AE instrument.  It operates using application specific software designed for data acquisition during field testing and has several utilities for post test analysis.  Some of the key features of this software is its ability to perform three dimensional source location and to classify different types of AE signals (faults) using neural networks.