In this research paper design, analysis and comparison of single stage and two stages Photovoltaic inverter connected to weak grid system is executed in terms of their maximum power point tracking, DC link voltage regulation, power factor and overall efficiency. Majority of the commercial and industrial loads are inductive in nature and result in a very low lagging power factor. However renewable energy sources have no reactive power generation and lagging power factor results in a weak grid system. For this purpose control mechanism comprises of three objectives is proposed in this research paper. These objectives are to obtain highest amount of power from photovoltaic array, the power must be deliver from photovoltaic array into the utility grid at unity power factor and to maintain desired voltage at the input of the inverter. In order to achieve these objectives nonlinear control mechanism of Photovoltaic inverter connected to weak grid system is established and implemented based on accurate mathematical modeling and by using Backstepping technique and Lyapunov Stability analysis. PI controller is used for the purpose to maintain desired voltage at input of the inverter according to the requirement of inverter. Both single stage and two stage models are developed and simulated in Simulink/Matlab environment.
Naveed Malik Sami Ullah Amir Khan and Farhan Ullah Designing and Analysis of Single Stage and Two Stage PV Inverter Connected to Weak Grid System International Journal of Engineering Works Vol. 7 Issue 10 PP. 361-368 October 2020 https://doi.org/10.34259/ijew.20.710361369.
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