Suppression of Double-Frequency Ripple with Fuzzy Control Based Single-Phase Pv Quasi-Z-Source Inverter

Abstract

according to the single phase photovoltaic system (PV), which exist a double frequency mismatch that exist between the dc input side and ac output side. To buffer out the double frequency ripple energy it is necessary to required. A capacitance reduction control strategy is proposed to buffer the DFR energy in single-phase Z-source/quasi-Z-source inverter applications is proposed in this paper. In single-stage photovoltaic (PV) system, there is a power irregularity exist between the AC yield and DC input. Here we are using the fuzzy logic controller, because it has many advantages comparing to other controllers. Such as, the fuzzy controller is the most suitable for the human decision-making mechanism, providing the operation of an electronic system with decisions of experts.  The double-frequency ripple (DFR) energy needs to be buffered by passive network. The ripple energy will flow into the input side and adversely affect the PV energy harvest. In a conventional PV system, due to their high capacitance electrolytic capacitors are usually used. Electrolytic capacitors are considered to be one of the most failure prone components in a PV inverter. The proposed control strategy can significantly reduce the capacitance requirement and achieve low input voltage DFR. Consequently, highly reliable film capacitors can be used. Due to the proposed control strategy the increased switching device voltage stress and power loss will also be discussed. By using the simulation results we can analyze the proposed method.