To eliminate the input current distortion caused by irregular switching signals at sector boundaries and the narrow pulses near voltage zero-crossing points in three-phase current source rectifiers(CSR)under conventional symmetric or asymmetric space vector pulse width modulation(SVPWM)

an improved asymmetric modulation strategy was proposed. Based on the vector action sequence of three-phase CSR conventional SVPWM

the mechanisms of the input current distortion and narrow-pulse generation were analyzed. The proposed novel asymmetric modulation was proposed and the implementation method was given

in which the zero current vectors were distinguished by optimizing the current vector action sequence

so that the vector action sequence remained unchanged during odd-even sector transitions and the pulse width of switching signals near voltage zero-crossing points was increased. Consequently

the input current distortion at sector boundaries was suppressed

the narrow pulses were eliminated

and the input current quality was improved. The feasibility and effectiveness of the proposed asymmetric modulation are verified through comparative simulations and experimental prototype tests.