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Title: "Design and Analysis of a Three-Phase Inverter for Photovoltaic Applications"

The aim of this paper is to propose a new design of a three-phase inverter suitable for photovoltaic (PV) systems. The proposed inverter is based on a two-stage design, which has been optimized for maximum efficiency and reliability.
1. What is the purpose of the paper?
2. What type of inverter is proposed in the paper?
3. Is the proposed inverter design optimized for efficiency?
4. What type of system is the proposed inverter suitable for? 
5. How many stages is the proposed inverter based on?