Diagnostic method based on the analysis of the vibration and acoustic emission energy for emergency diesel generators in nuclear plants

Ensuring the availability and reliability of the Emergency Diesel Generators (EDGs) in nuclear power plants is a critical aspect to guarantee the plant safe shutdown in case of an emergency scenario. An effective engine diagnosis method is essential to fulfill that goal. For that purpose, this paper presents a fast and automatic engine diagnosis method based on a single parameter: the vibration/AE signals energy. The method is based on the comparison of the vibration and AE energy with reference values to determine whether the engine condition is faulty. The method was applied in a test engine, and proved to work satisfactorily. Therefore, it was used to diagnose the EDGs in a nuclear power plant, where regular rigorous inspections are effected periodically. An injector fault was detected thanks to the diagnosis method.