7Zhang S,Zhang B H,You M. Realization of the transient-based boundary protection for HVDC transmission lines[A].Hangzhou,China:CSEE,2010.1-7.
8Liu Xiaolei,Osman A H,Malik O P. Hybrid travelling wave/boundary protection for monopolar HVDC line[J].IEEE Transactions on Power Delivery,2009,(24):569-578.