Aiming at the problems of poor timeliness

low reliability and lack of commutation failure identification in existing commutation failure detection schemes in high voltage direct current (HVDC) engineering

this paper proposes a commutation failure identification and detection scheme based on valve-side current characteristics in different time periods. First

the occurrence and development process of commutation failure is analyzed

and the types of commutation failure are identified. Then

based on the commutation loop

the analytical formulas of the valve-side currents are obtained

and the time periods of different commutation failures are determined. Based on the dynamic characteristics of valve-side current variation amplitude and waveform extremum in different time periods

a fast recognition and detection method for different commutation failure types is proposed. Finally

the proposed scheme is simulated and verified in Gui-Guang-Ⅱ and Three-Gorge-Shanghai DC project models respectively

and the influence of AC fault severity and control period on the scheme is analyzed. Simulation results show that the proposed scheme has obvious advantages in timeliness

reliability and identification ability compared with the existing schemes.