[IEEE 2018 International Power Electronics Conference (IPEC-Niigata 2018 –ECCE Asia) - Niigata, Japan (2018.5.20-2018.5.24)] 2018 International Power Electronics Conference (IPEC-Niigata 2018 -ECCE Asia) - A Novel Single- Stage High-Frequency Boost Inverter Cascaded by Rectifier-Inverter System for PV Grid-Tie Applications

摘要： This paper proposes a new topology for a single-phase grid-tie two-stage DC-AC boost inverter for the application of PV systems that utilize high-frequency transformer (HFT) for galvanic isolation. In the first stage, a new single-stage high-frequency boost inverter (HFBI) is proposed to boost and convert the DC output voltage of the PV modules to a high-frequency single-phase square waveform and to realize maximum power point tracking (MPPT). The second stage is rectifier-inverter system (RIS) that interfaces HFBI to the grid. Therefore, a single-phase high-frequency transformer is used to link both stages and to provide galvanic isolation between the AC and DC sides. The proposed topology has many advantages such as increasing the inverter output voltage level, MPPT, high reliability, small size and lightweight. In addition, a proportional integral current control (PI) conventional is used to inject a sinusoidal current into the grid at unity power factor. The proposed topology has been verified analytically by using PSIM software and experimentally by using a laboratory prototype.