A novel Web based Expert System Architecture for on-line and off-line fault diagnosis and control (FDC) of transformers

The paper presents the structure and usage mode for an integrated fault-diagnosis and control system for transformers. The fault diagnosis and control system allows online analysis on a desktop application, a Web application and offline analysis for determining the transformer faults and remedies based on certain symptoms observed on the equipment and their comparison with the survey results of cooling system condition, bushing condition, insulation system condition, partial discharge evolution, transformer switching in/switching off, exceeding of monitored parameter limits and estimation of remained life, the data of which is continuously updated into the database of the existing system. The proposed FDC system uses a Web based expert system architecture which has been proven as an effective platform for diagnostic and control applications of transformers. Conventional expert systems [1] are PC based and are not of much use where the expertise is required over a large network. The advent of the Internet has strongly influenced modern power systems. A Web based expert system [2] with knowledge base and database connectivity is a novel architecture and is an apt solution for both on-line and off-line applications. The purpose of this work is to develop a web based expert system shell and then use it for the fault diagnosis and control (FDC) [3] of transformers either off-line (on a stand alone system) or on-line through the Internet with the facility of on-line up gradation of data related to periodic monitoring and maintenance of transformers. The proposed system goes beyond imitation of expert- operators´ knowledge, being able to inference fault scenarios using both knowledge base and database of the required equipment with no limitation to the number of pieces of equipment being handled. It is easier, flexible, and more user friendly. It can be used for both stand-alone (off-line) and Web- based (on-line) applications.