AN INVESTIGATION INTO THE DEVELOPMENT OF A CONDITION MONITORING/FAULT DIAGNOSTIC SYSTEM FOR LARGE REVERSIBLE FRANCIS TYPE PUMP-TURBINES

摘要

Dinorwig Power Station is one of the world's largest hydro-electric pump storage schemes. The station consists of six 300MW Francis-type Pump-Turbines, with each 520 tonne assembly being suspended via a support bracket and a set of oil lubricated thrust bearing pads. Dinorwig performs a critical role in the UK National Grid system due to its ability to provide almost instantaneous power. Each of the machines must operate under an arduous regime in comparison with thermal base-load units, with each unit performing up to twenty-five mode change sequences per day. With such a regime the reliability of such plant is of critical importance in today's competitive electricity market. After carrying out an initial investigation into what useful information could be obtained from information currently monitored to determine the health of the plant, the authors are to continue a stage further and develop a condition monitoring and fault diagnostic system suitable for the machines at Dinorwig. In conjunction with developing the system, an assessment will be made of the improvements in the general condition of a unit which will have a new magnetic thrust bearing installed this year. The main purpose of the bearing is to reduce the load experienced by the thrust bearing at various power loads. This paper summaries the initial development work being carried out in order to identify the most appropriate monitoring parameters, analysis techniques and data acquisition systems required to achieve an effective condition monitoring and fault diagnostic system.