Electric power systems have become much more complex in the past years, due to the integration of distributed generation including renewable energy sources and the challenges caused by intermittency of renewables. This complexity makes power systems potentially more vulnerable. However, use of computer-based protection methods (i.e., digital protection relays) supported by communication technology have helped in protecting electrical networks from faults to which they are subjected to. This second edition of the book covers a comprehensive introduction to the protection of electrical power systems using digital protective relays. The new edition offers a thorough revision and update, and comprehensive additional material. Chapters treat the mathematical background of protection algorithms including, sinusoidal-wave-based algorithms, Walsh function and S-Transform-based techniques, least squares and differential equation-based techniques, travelling wave-based protection, protection of transformers, digital line differential protection, a comparison between digital protection algorithms, and importantly, protection of networks with distributed generation including renewable energy resources. The book is written for researchers in electrical engineering and power engineering, in industry, utilities and universities, and for advanced students. The treatment is logically structured, covering mathematics and principles for the development and implementation of the major algorithms underlying different protection techniques. These techniques can be applied to protection of generator transformers, lines, switchgear and cable circuits: the main components of transmission and distribution systems with and without integrated distributed energy sources including renewables.

Digital protection is based on the use of computers in power line relaying. Since the late 1960s, digital devices and techniques have been applied to almost all new protection schemes. Today the technology is moving towards standardised hardware platforms; at the software level, however, there remains a huge variety in approaches and protection algorithms. This book gives a fairly detailed understanding of the principles and techniques underlying the application of digital technology and algorithms to protection. It avoids going into detail of specific products: up-to-date information on these is available from the manufacturers. Instead it aims to give the reader a thorough understanding of the generic problems of digital protection. The text covers the mathematical basis of numerical techniques and relay algorithms, the basic elements of digital protection and the fundamentals underlying the commonest algorithmic forms, particularly as applied to line protection. It deals with the fundamentals of travelling-wave techniques and their application to transmission lines, and with digital differential protection of transformers and lines.