Triple-Mode Flying Inductor Common-Ground PV Inverter With Reactive Power Capability and Low Semiconductor Component Count

Abstract

This paper proposes the flying inductor based common ground single-phase PV inverter which can support reactive power to the ac grid. The proposed buck-boost transformerless PV inverter eliminates the leakage current and is suitable for use in on-grid applications which require active and reactive power support. The proposed converter also features a low number of semiconductor devices, no ac type capacitor, acceptable quality of the grid side current even during non-unity power factor operations, reducing switching loss by adopting time-sharing technique, and high efficiency. The converter uses a dead-beat controller in the control loop which has a smooth, accurate and fast response. Experimental results for a 500 W, 100 Vdc and 180 Vdc to 110 Vrms, prototype is provided in a closed-loop system in the presence of the proposed dead-beat controller. The results from the prototype validate the theoretical analysis and the applicability of the proposed structure. The converter exhibits the capability for stepping up the dc to ac power conversion and demonstrates a peak efficiency of 97.2% and 96.8% from 180 Vdc and 100 Vdc, respectively.