THE APPLICATION OF EXPERT-SYSTEMS TO FAULT-DIAGNOSIS IN ALTERNATORS

This Paper describes the development of an expert system demonstrator for fault diagnosis in alternator seal oil, hydrogen cooling and stato r-winding water auxiliary systems. It is clear from wide experience th at improved plant diagnostic capability can be achieved by the applica tion and use of better condition monitoring tools, which offers the po tential benefits of enhanced alternator reliability and lifetime manag ement. Another important potential benefit is the ability of the opera tor to make the correct diagnosis during operational incidents when un der extreme pressure. Existing monitoring systems are not generally ex tensive enough and do not contain the necessary intelligence to offer these benefits. In particular they do not have the ability to interpre t plant sensor information, perform the necessary online analysis or t rending and provide the operator with the necessary clear and easily u nderstand guidance. Advice on alternator problems has traditionally be en obtained from plant specialists, but their expertise is now becomin g very, scarce. Expert system technology is seen as one vehicle whereb y such experience can be captured and structured into a knowledge base suitable for plant operators. This Paper describes the development of an expert system designed to meet the above functional requirements a nd concerns. The Paper contains an outline of the principal duties of the alternator support systems, discusses the approach to knowledge ac quisition, modelling and analysis, and describes the expert system des ign. Examples of expert system diagnosis of typical alternator system problems are presented.