Analysis of distance protection’s operation in cases of deep saturation of current transformers

There is usually no information about permissible error of current transformers in modes succeed by large relative short-circuit current, at which microprocessor-based protections operate stably. By this reason, it necessary to use data, defined for analog relays. It leads value appreciation a project because often essential reduce transformers’ case short circuit fault. Therefore, define the error, permitted impedance Conclusions fundamental and applied sciences (mathematical analysis, theoretical foundations electrical engineering, theory simulation), analytical methods researching nonlinear circuits digital signal processing were used. A simulation model was created setting overall tests trans-former (CT) system. relay protection device that reflected all important properties studied objects allowed an analysis distance protection’s operation high levels currents. The factors influ-encing over deep saturation CTs revealed, certain algorithm definition CT errors proposed. Stable observed fault nearby place theoretically possible combinations system’s power length protected electric transmission line. valid if load choice carried with account stable condition computational point voltage swell secondary wirings infeasible.