Development of GIS type surge arrester applying ultra high voltage gradient ZnO element

Continuous efforts have been made to miniaturize surge arresters. The authors have been striving to increase the operating voltage of the ZnO elements of surge arresters, and make them more compact by reducing the number of the ZnO elements, and have succeeded in developing new ZnO elements with globally unrivaled operating voltage (Ultra high voltage gradient ZnO elements). Applying such ultra-high voltage gradient ZnO elements enables the design to be optimized and facilitates the development of the world´s most compact surge arresters.