Translated Title
Three-Phase Voltage-Fed Quasi-Z-Source Photovoltaic Grid-Connected Inverter System With Repetitive Control
Translated Abstract
In order to improve boost capability of quasi-Z-source inverter and grid-connected current quality, a single-stage three-phase voltage-fed quasi-Z-source photovoltaic grid-connected inverter system with strong boost capability with repetitive control is proposed. Circuit topology, control strategy of modified space vector pulse width modulation (SVPWM), system stability and modulator design under discrete control system were researched. The circuit topology is composed of a high boost ratio quasi-Z-source impedance network, a three-phase inverter bridge and a three-phase LCL filter. The modified SVPWM control strategy includes control for maximum power point tracking (MPPT) of photovoltaic array and outer loop control for energy storage capacitor voltage with inner loop control for grid-connected current. Inverter-side current feedback control strategy is used in grid-connected current inner loop with grid voltage proportional feedforward, repetitive control and PI series embedded composite control to improve grid-connected current quality. Experiment results show validity of the inverter system topology, control strategy and system design.
Translated Keyword
inverter-side current feedback
maximum power point tracking
modified space vector pulse width modulation
photovoltaic
quasi-Z-source inverter system
repetitive control
Access Number
WF:perioarticaldwjs201706039
