Method for determining an impedance proportional to the distance between a fault location and a measuring location in asymmetrical energy transmission lines

摘要

The impedance value is proportional to the distance between a fault location and the measurement position at which the currents and voltages of the transmission lines are measured. A summation current compensation matrix is formed using a given summation current equation involving the summation current, the measured conductor currents, the null system impedance and the with system impedance. The summation current compensation matrix is converted into a phase current compensation matrix by replacing a unit matrix with a complex symmetrical correction matrix so that the summation current and conductor current compensation matrices are identical. The impedance in the distance safety arrangement is compared with stored reference values. A power switch connected to the power transmission lines is triggered or not depending on the comparison result.