Out-of-Step Relaying Principles and Advances

Antans Saulus Sauhats is a professor and Director at the Power Engineering Institute of Riga Technical University, Latvia. He holds Dr. Sc. ing and Dr. habil. Sc.ing degrees in power system control and network operation optimisation. He is a corresponding member of the Latvian Academy of Sciences, a longtime member of  the Latvian Electrical Engineering Society and a member of International Scientific Committees of Latvian, Lithuanian, Polish and Slovak Scientific Simposiums and conferences. Having more than 45 years of experience, Professor Sauhats is a well-known authority in the field of power system control and optimisation. He is the author of over 350 scientific publications and leads many Latvian and international research projects. His research specialty and interests include power system stability, power plant control and operation optimisation, high voltage transmission line fault location, protection relays and power system automation-related issues. He is the author of the idea and the scientific director of the out-of-step protection system, which is widely used nowadays in the power system of the Baltic States.

Andrejs Utans received a Dr. Sc. ing degree from Riga Technical University in 1997. He is currently a professor at the Faculty of Electrical and Environmental Engineering of Riga Technical University. He is a leading researcher in several international and Latvian scientific projects and has more than 25 years of experience in the field of protection relays and automation systems. He is an author of more than 25 scientific publications. His current research is focused on power system stability and system resiliency-related problems. In addition to purely theorethical aspects of the problem, his area of interest is also a possible practical implementation of the problem being solved. He is also a developer and the technical director of out-of-step protection terminals, which are used in power system presently.