For the special requirements of grid-connected inverter used in wind power generation system, a kind of three-phase Z-Source inverter operational principle is analyzed in this paper. Formulas for the design of main parameters under the control of constant duty cycle of shoot-through switching state are derived. Then the simulation models of SVPWM with shoot-through zero vectors are established by using Matlab/Simulink in order to control the switches of Z-Source inverter on and off. The independent control strategy of d-axis and q-axis currents is used to achieve a unity power factor grid-connected aim. Simulation results show that the theoretical analysis and the simulation models are validity.