Equipment health management assessment of nuclear condensate pump motor stators

The problem of minimising the number of unplanned outages for nuclear power stations is receiving continuing attention as operators endeavour to maximise generation. Equipment Health Management (EHM), is commonly employed by operators of large plant installations in order to detect developing failures and allow mitigating action to be taken prior to the plant tripping. This paper presents an a posteriori analysis of the electrical failure of a condensate pump motor stator at a nuclear power station. Limited pump operating data, recorded by the existing plant computer, are processed using three well known EHM techniques. It is shown that, using a model of normality, deterioration in the stator condition could have been observed before the final failure, allowing the operator to undertake preventative maintenance. This EHM could have been implemented with minimal capital expenditure using the existing plant monitoring system and without the installation of any EHM specific instrumentation. (authors)