POWER TRANSFORMER ADAPTIVE DIFFERENTIAL CUTOFF

摘要

The article proposes the method to increase the sensitivity of power transformer differential cutoff by changing its setpoints depending on operating conditions of power equipment. It was shown that using control contacts of currents breakers is the optima) way to control operating conditions of the power transformer, so the differential cutoff setpoints should be changed depending on current breakers position. Approximately, sensitivity of differential cutoff can be increased by 1.5-2.0 times. Applying additional equipment requires its health control since fail to reliably determine the current positions of current breakers may lead to false operation of differential protection, so the algorithm controlling health conditions of control contacts was also proposed.