A Deadbeat Grid一connected Control Strategy of the Single Phase Z/Q一Z Source Inverter

Abstract

In order to improve the efficiency of Z/Q-Z source inverter and output current quality，reduce the harmonic distortion rate of grid-connected current，the control strategy of grid-connected current is applied to the Z/Q-Z source inverter. The deadbeat control is used to realize grid-connection control，The current can track the reference current quickly，realize the single power factor operation，and the digital control of the inverter. Z/Q-Z source grid-connected inverter simulation model is established，and the grid-connected system of Z/Q-Z source in- verter is simulated and analyzed to prove the validity and feasibility of the grid-connected control strategy. The sim- ulation results show that the total harmonic distortion rate of the grid-connected current is less than 1%，the quality of grid-connected current is improved，and the capacitor voltage value of Q-Z source inverter is about half order of magnitude smaller than the Z inverter network. Moreover soft start control of the Z/Q-Z source inverter is analyzed， soft start can effectively solve the start impact of the Z source capacitor voltage and inverter bridge voltage.

Keywords

• control without difference; single phase grid connected; Z/Q-Z source inverter; soft start control