Aiming at the existing 100 Hz protection using only a single device measurement information for fault judgment

the action response of the protection is blind to a certain extent

and its adaptability is insufficient when the AC area of converter station fails. It is proposed to distinguish the DC area fault from the AC area fault of rectifier station based on station domain information

which realizes 100 Hz protection optimization and gives 100 Hz protection the ability to identify the DC area fault and the AC area fault of rectifier station. Based on the cause analysis of misoperation of 100 Hz protection

the correlation coefficient between the negative sequence voltage of converter bus fundamental frequency and the second harmonic voltage of DC line is proposed

and the fault area identification method of rectifier station is constructed. The simulation results show that the method is not affected by fault type

fault location

transition resistance

fault initial angle and noise interference

and has high reliability.