The Analysis of Electric Arc Impact on Distance Relay Measurement Error

Most faults in electric power networks are nonmetallic, which means that an electric arc occurs at the location of the fault. Electric arc resistance introduces an error into the measurement of the distance relay impedance. This error can lead to an irregular operation of the distance protection, particularly in short lines, since the measured impedance is higher than the actual impedance, which can cause a delay in the disconnection of the fault. This paper analyzes the influence of double-end fed faults in the case when an electric arc occurs. The analysis was conducted using a three-phase transmission line model created with the MATLAB/Simulink software package.