Analysis of travelling wave protection criterion performance for double-circuit HVDC

Owing to the narrow transmission line corridors, double-circuit HVDC transmission line on the same tower has been put into engineering construction. Based on the lines transposed fully, the characteristics of fault travelling-wave in double-circuit and single-circuit HVDC is compared firstly. And then referring to the actual calculation method of criterion for travelling-wave protection, the changes of setting value in double-circuit on contrast of single-circuit are discussed. Finally, the operating ability of two travelling-wave protection schemes in double-circuit HVDC is contrastively discussed.