Modelling and Control of a Solar Micro-Inverter

Abstract

This project aims to design and control a Solar Micro-Inverter using classical PI and PID controllers. This type of inverter is used in low-power (less than 2 kilowatts) standalone photovoltaic systems. The inverter structure is based on two stages: the first stage consists of a static DC-DC push-pull converter based on a High-Frequency transformer, which ensure a galvanic isolation between the input and output circuits. This feature is crucial for protection against hazards. Using a high-frequency transformer also reduces the weight and size of the overall inverter. The second stage consists of a DC AC Full-Bridge Inverter that allows for the production of alternative voltage and current. During this study, each stage is modeled and controlled separately, then the both of them are joined together and controlled. The system was tested under variations in both input and load conditions. The results obtained were highly satisfactory and demonstrate the effectiveness of the designed controllers.