Instrument current transducers with Rogowski coils in protective relaying applications

The purpose of this work is informing the scientific community and vendors of a certain type of instrument transducers for protection and control applications in industrial electric installations. Such transducers can increase the accuracy and decrease the size of the measuring system for all service conditions at any industrial facilities. The work contains circuit diagrams of negative sequence current transducers offered by the author and obtaining primary currents from Rogowski coils. The statistical data based on the field tests of the discussed equipment is also presented in the paper. The algorithm for calculation of parameter values for negative sequence current transducers is discussed.The paper may be of interest for investigators and engineers engaged in research, design and commissioning of protection and control equipment, current instrument and measurement devices used in industrial applications, and also for undergraduate and postgraduate students in electrical engineering.