1. Introduction

CIGRE is the only organization worldwide which for almost 100 years, since 1921, has dedicated its activities to the work of the electricity supply industry. During this time the Substations Study Committee has addressed many and varied topics associated with all aspects of high voltage substations, and this work has been published in the form of Technical Brochures, Electra Papers, Session Papers, and Symposium and Colloquium Papers, and the majority of these are available freely to CIGRE members through the e-CIGRE website. However, these papers usually address specific topics which were particularly relevant or “hot topics” at the time they were written. This means that if one wishes to consider all aspects of high voltage substations, it is not easy to find your way around this mass of information. The purpose of this book is to draw on this wealth of information and to present it in a more accessible and comprehensive way in order to provide a reference book on all aspects of high voltage substations which would be of value to all decision-makers working in this field of expertise. It is hoped that this book will become a standard reference work, present on the bookshelves of all such colleagues.