Analysis of synchronous generator internal insulation failures

Winding insulation failures within a synchronous generator cause extensive damage and are expensive to repair. The understanding of the machine behavior during internal failures is very important for the full protection of the machine. Within the literature, little is written relating to modeling, analysis, and experimental testing of synchronous generators during internal fault conditions. This paper provides a summary of an experimental approach taken to capture this phenomenon. These results discuss real-time measurements taken during controlled internal faults on a laboratory scale generator. This data were also compared to data recorded by protective relays during an evolving internal insulation failure of a 145 MVA utility generator