The contract was awarded to Quartzelec following the discovery of high partial discharge, resulting from electrical degradation of the original stator winding. The project was split into two phases at the request of the customer.

Phase one involved the redesign and manufacture of a new core (using TS Metals’ Trumpf laser cutting machine), with stator coils from Quartzcoil and Rugby factory building the stator core and winding the replacement stator – a Unipak type generator. This process was completed last October.

Phase two included exchange of the wound core into the stator, which was carried out at Rugby, and then reinstallation on customers’ site. January saw the unit lifted out of its plinth and delivered to Rugby workshop, where it was fitted with the new wound core, and other components refurbished or replaced by spares previously purchased by the customer. After the unit had been reassembled, it was ‘light run’ tested at Rugby test facility and delivered back to the customer ahead of the required delivery date. The unit was put back into operation in earlier this year, coinciding with the completion of the plant’s maintenance shutdown.