With the rapid promotion of new energy

flexible DC transmission and other technologies

the proportion of power electro-nic equipment in the power grid is gradually increasing.The rapid adjustment performance of AC current amplitude and phase angle brings varying degrees of impact to the directional components of traditional line protection.It proposes a line protection device as a directional component for distance protection of high-voltage lines.The fault direction is correctly identified by using the method of non-fault phase voltage to judge the asymmetric fault direction.The simulation test is carried out according to the actual system on site.Compared with the original negative sequence direction identification method

this method is more effective.The fault direction can be correctly identified in the case of weak feedback characteristics on the new energy side

which verifies the effectiveness of the method.