Power Loss Analysis of Solar Photovoltaic Integrated Model Predictive Control Based On-Grid Inverter

This paper presents a finite control-set model predictive control (FCS-MPC) based technique to reduce the switching loss and frequency of the on-grid PV inverter by incorporating a switching frequency term in the cost function of the model predictive control (MPC). In the proposed MPC, the control objectives (current and switching frequency) select an optimal switching state for the inverter by minimizing a predefined cost function. The two control objectives are combined with a weighting factor. A trade-off between the switching frequency (average) and total harmonic distortion (THD) of the current was utilized to determine the value of the weighting factor. The switching, conduction, and harmonic losses were determined at the selected value of the weighting factor for both the proposed and conventional FCS-MPC and compared. The system was simulated in MATLAB/Simulink, and a small-scale hardware prototype was built to realize the system and verify the proposal. Considering only 0.25% more current THD, the switching frequency and loss per phase were reduced by 20.62% and 19.78%, respectively. The instantaneous overall power loss was also reduced by 2% due to the addition of a switching frequency term in the cost function which ensures a satisfactory empirical result for an on-grid PV inverter

Importance of Wolbachia-mediated biocontrol to reduce dengue in Bangladesh and other dengue-endemic developing countries

Mosquito-borne diseases, particularly dengue and chikungunya have become global threats, infecting millions of people worldwide, including developing countries of Southeast Asia and Latin America. Bangladesh, like many other developing countries, is experiencing frequent dengue outbreaks. This article, therefore, critically discussed the current status of dengue disease, vector control approaches, and the need for Wolbachia-mediated intervention in Bangladesh and other dengue-endemic developing countries. In this narrative review study, relevant literature was searched from major databases and search engines such as PubMed, BanglaJol, World Health Organization (WHO)/European Centre for Disease Prevention and Control (ECDC) and Google Scholar. Considering the selection criteria, our search strategies finally involved 55 related literature for further investigation. Findings showed that current vector control strategies could not render protection for an extended period, and the disease burden of arboviruses is increasing. The impoverished outbreak preparedness, urbanization, climate change, and less efficacy of existing control methods have made people susceptible to vector-borne diseases. Hence, Wolbachia, a naturally occurring endosymbiont of many mosquito species that can potentially limit virus transmission through several host genetic alterations, would be a potential alternative for dengue prevention. We also critically discussed the challenges and prospects of Wolbachia-based dengue control in developing countries. The evidence supporting the efficacy and safety of this intervention and its mechanism have also been elucidated. Empirical evidence suggests that this introgression method could be an eco-friendly and long-lasting dengue control method. This review would help the policymakers and health experts devise a scheme of Wolbachia-based dengue control that can control mosquito-borne diseases, particularly dengue in Bangladesh and other developing countries