Design of HVDC converter station equipment subject to severe seismic performance requirements

Severe seismic design levels were specified for the upgrading of the HVDC link between the principal islands of New Zealand. A number of novel design solutions were required to fulfil the performance requirements for the electric equipment. The purpose of this paper is to give an overview of design solutions and verification methods in the light of a specification stating performance criteria rather than specific allowables. Modifications to items of high voltage electrical equipment are described that reduce the seismic loads in the equipment and enable standard equipment to be used in areas of high seismicity. The seismic performance is further improved by controlling the eventual collapse mechanism