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Single-Phase Bridgeless Zeta PFC Converter with Reduced Conduction Losses
Shakil Ahamed Khan,Nasrudin Abd. Rahim,Ab Halim Abu Bakar,Tan Chia Kwang 전력전자학회 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.2
This paper presents a new single phase front-end ac?dc bridgeless power factor correction (PFC) rectifier topology. The proposed converter achieves a high efficiency over a wide range of input and output voltages, a high power factor, low line current harmonics and both step up and step down voltage conversions. This topology is based on a non-inverting buck-boost (Zeta) converter. In this approach, the input diode bridge is removed and a maximum of one diode conducts in a complete switching period. This reduces the conduction losses and the thermal stresses on the switches when compare to existing PFC topologies. Inherent power factor correction is achieved by operating the converter in the discontinuous conduction mode (DCM) which leads to a simplified control circuit. The characteristics of the proposed design, principles of operation, steady state operation analysis, and control structure are described in this paper. An experimental prototype has been built to demonstrate the feasibility of the new converter. Simulation and experimental results are provided to verify the improved power quality at the AC mains and the lower conduction losses of the converter.
Single-Phase Bridgeless Zeta PFC Converter with Reduced Conduction Losses
Khan, Shakil Ahamed,Rahim, Nasrudin Abd.,Bakar, Ab Halim Abu,Kwang, Tan Chia The Korean Institute of Power Electronics 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.2
This paper presents a new single phase front-end ac-dc bridgeless power factor correction (PFC) rectifier topology. The proposed converter achieves a high efficiency over a wide range of input and output voltages, a high power factor, low line current harmonics and both step up and step down voltage conversions. This topology is based on a non-inverting buck-boost (Zeta) converter. In this approach, the input diode bridge is removed and a maximum of one diode conducts in a complete switching period. This reduces the conduction losses and the thermal stresses on the switches when compare to existing PFC topologies. Inherent power factor correction is achieved by operating the converter in the discontinuous conduction mode (DCM) which leads to a simplified control circuit. The characteristics of the proposed design, principles of operation, steady state operation analysis, and control structure are described in this paper. An experimental prototype has been built to demonstrate the feasibility of the new converter. Simulation and experimental results are provided to verify the improved power quality at the AC mains and the lower conduction losses of the converter.
Salmiah Jamal Mat Rosid,Azman Azid,Aisyah Fathiah Ahmad,Nursyamimi Zulkurnain,Susilawati Toemen,Wan Azelee Wan Abu Bakar,Ahmad Zamani Ab Halim,Wan Nur Aini Wan Mokhtar,Sarina Mat Rosid 대한환경공학회 2023 Environmental Engineering Research Vol.28 No.1
Developed countries are increasing their demand for natural gas as it is an industrial requirement for fuel transportation. Most of modern society relies heavily on vehicles. However, the presence of CO₂ gas has led to the categorization of sour natural gas which reduces the quality and price of natural gas. Therefore, the catalytic methanation technique was applied to convert carbon dioxide (CO₂) to methane (CH₄) gas and reduce the emissions of CO₂ within the environment. In this study, samarium oxide supported on alumina doped with ruthenium and manganese was synthesized via wet impregnation. X-ray diffraction (XRD) analysis revealed samarium oxide, Sm₂O₃ and manganese oxide, MnO₂ as an active species. The reduction temperature for active species was at a low reaction temperature, 268.2℃ with medium basicity site as in Temperature Programme Reduction (TPR) and Temperature Programme Desorption (TPD) analyses. Field Emission Scanning Electron Microscopy (FESEM) analysis showed an agglomeration of particle size. The characterised potential catalyst of Ru/Mn/Sm (5:35:60)/Al₂O₃ (RMS 5:35:60) calcined at 1,000℃ revealed 100% conversion of CO₂ with 68.87% CH₄ formation at the reaction temperature of 400℃. These results were verified by artificial neural network (ANN) with validation R² of 0.99 indicating all modelling data are acceptable.