Development of Current Controlled Grid-connected Microinverter for PV applications

Document Type : Original Article

Authors

University of Science and Technology at Zewail City, Egypt.

10.21608/iugrc.2022.302521

Abstract

Modern grid connected PV systems are becoming an integral part of zero net energy PV building integrated systems. Grid connected PV system topologies play a great role in harvesting the maximum available energy and determine the overall system efficiency. This work presents the development of a two-stage PV grid connected microinverter. The microinverter topology is based on using a low frequency transformer with a boost converter for the maximum power point tracking stage. The implementation phases included SIMULINK simulations and hardware development. Simulations of low frequency transformer-based topology achieved a system efficiency of 95 % with total harmonic distortion (THD) of 3%. The topology has proven an efficient tracking of the PV maximum power and DC link voltage set point. The hardware boards, DC-DC converter, DC-AC inverter, and control boards were all assembled and connected to the grid through a low-frequency transformer. The hardware achieved a conversion efficiency of the input energy of 94%.

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