Abstract:

With the high voltage grid 6 kV in mine is not equipped measurement transformer type HTMИ-6 problems installing equipment to protect earth fault to ground selectivity become very difficult and not feasible. In order to resolve this problems, the author proposed one equipment earth fault protection of single-phase to the ground with special input circuit. The proposed solution is just to use the currents transformer BI with 02 operational amplifiers algorithm for separating two signal 3Io and 3Uo for operation. Using the applicated functions of operational amplifier to perform the task