Voltage source converters（VSC）in operation generate harmonic

leading to pollution to the power grid.Thus

it is necessary to set up its harmonic analysis model in order to analyze its harmonic generation mechanism and interaction rule.In this paper

the mathematical model of single-phase-three-level neutral point clamped voltage source converter under time-domain is analyzed firstly

the dynamic phasor model of switching function at different modulations is set up and the time-domain model is transferred into the dynamic phasor harmonic analysis model.Then

contents of harmonic for current at AC side and voltage at DC side are obtained at different modulation on the basis of Runge-kutta method.After that

the correctness of the proposed harmonic analysis model is verified by simulation analysis and generation mechanism and interaction rule for the current at AC side and voltage at DC side is revealed through the analysis of the dynamic phasor model of the single-phase-three-level neutral point clamped voltage source converter.