High-speed fault identification and protection for HVDC line using wavelet technique

This paper describes a new high-speed HVDC line protection using wavelet technique. Based on the representation of the travelling waves through wavelet modulus maxima, the protection criteria for HVDC fine are proposed. Simulations are carried out for testing the criteria. The influences of similar faults are discussed. The protection can detect the HVDC line fault well and identify the HVDC line fault clearly from the similar transients, such as commutation failure and AC single phase fault.