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RISS 인기검색어
- 검색키워드
- 저자 : Premkumar, N. (검색결과 57 건)
- 무료
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Design and Implementation of New Topology for Solar PV Based Transformerless Forward Microinverter
Premkumar M,Sumithira T.R 대한전기학회 2019 Journal of Electrical Engineering & Technology Vol.14 No.1
Recently, transformerless inverters play a vital role for single phase low voltage solar photovoltaic (PV) due to low cost, lesser weight, small size and high efficiency. However, the leakage current produces electromagnetic interferences (EMI), current distortion on the grid with additional losses which affects the performance of the inverter. In this paper, a new inverter topology, to deal with the problem of leakage current is proposed. The various conventional H6 topologies are simulated, compared and evaluated based on the leakage current, performance and safety with the proposed inverter topology. This work focuses on transformerless inverter which is best suitable for Module Integrated Converter (MIC) or microinverter. The proposed topology is employed with unipolar sinusoidal pulse width modulation, and it can reduce the common mode (CM) current. The performance analysis is carried out on different topologies using MATLAB/Simulink environment and the proposed inverter experimentally verified on a 150W prototype. Based on the analysis, simulation and experimental results, the comparison also presented for future reference.
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Efficiently-designed Hybrid Tandem Photovoltaic with Organic and Inorganic Single Cells
Premkumar Vincent,Jin-Hyuk Bae,김혁 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.68 No.9
Conjugated polymers for solar-cell applications have been extensively studied and have proven highly beneficial in tandem solar-cell structures. This study focuses on achieving power conversion efficiencies of greater than 10% when in tandem with a highly efficient copper indium gallium diselenide (CIGS) solar cell. The optimal design is suggested based on the result of optical simulations on the organic-CIGS tandem structure. This is one of the first reports to show theoretically an organic-CIGS tandem solar cell to obtain an efficiency of greater than 10%. The best PCE was at a thickness of 200 nm for PTB7:PCBM, the active layer of the organic solar cell, and 400 nm for CIGS active layer. Our best datum showed an efficiency of 11.41% with a short-circuit current density of 11.56 mA/cm2 and a good spectral response at our optimized thicknesses.
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Premkumar M,Jangir Pradeep,Sowmya R,Alhelou Hassan Haes,Mirjalili Seyedali,Kumar B Santhosh 한국CDE학회 2022 Journal of computational design and engineering Vol.9 No.1
This paper proposes a new Multi-Objective Equilibrium Optimizer (MOEO) to handle complex optimization problems, including real-world engineering design optimization problems. The Equilibrium Optimizer (EO) is a recently reported physics-based metaheuristic algorithm, and it has been inspired by the models used to predict equilibrium state and dynamic state. A similar procedure is utilized in MOEO by combining models in a different target search space. The crowding distance mechanism is employed in the MOEO algorithm to balance exploitation and exploration phases as the search progresses. In addition, a non-dominated sorting strategy is also merged with the MOEO algorithm to preserve the population diversity and it has been considered as a crucial problem in multi-objective metaheuristic algorithms. An archive with an update function is used to uphold and improve the coverage of Pareto with optimal solutions. The performance of MOEO is validated for 33 contextual problems with 6 constrained, 12 unconstrained, and 15 practical constrained engineering design problems, including non-linear problems. The result obtained by the proposed MOEO algorithm is compared with other state-of-the-art multi-objective optimization algorithms. The quantitative and qualitative results indicate that the proposed MOEO provides more competitive outcomes than the different algorithms. From the results obtained for all 33 benchmark optimization problems, the efficiency, robustness, and exploration ability to solve multi-objective problems of the MOEO algorithm are well defined and clarified. The paper is further supported with extra online service and guideline at https://premkumarmanoharan.wixsite.com/mysite.
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Shape-tailoring of gold nanostructures: can a detergent act as the reducing or protecting agent?
Premkumar, Thathan,Kyungjae Lee,Geckeler, Kurt E. Royal Society of Chemistry 2011 Nanoscale Vol.3 No.4
<P>A commercially available detergent was found to be an effective reducing as well as stabilizing agent for the synthesis of differently shaped gold nanoparticles in an aqueous solution at an ambient condition and the as-prepared gold nanoparticles behave as an efficient catalyst for the reduction reaction of 4-nitrophenol at room temperature.</P> <P>Graphic Abstract</P><P>The synthesis of differently shaped gold nanoparticles can be performed in an aqueous solution at ambient conditions by using a commercial detergent that was found to be an effective reducing as well as stabilizing agent. In addition, the as-prepared gold nanoparticles were found to be able to act as an efficient catalyst for the reduction reaction of 4-nitrophenol at room temperature. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c0nr00853b'> </P>
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Premkumar, Manoharan,Sumithira, Rameshkumar The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.6
This paper proposes a novel hybrid maximum power point tracking (MPPT) algorithm combining a Whale Optimization Algorithm (WOA) and the conventional Perturb & Observation (P&O) to track/extract the highest amount of power from a solar photovoltaic (SPV) system working under partial shading conditions (PSCs). The proposed hybrid algorithm is based on a WOA which predicts the initial global peak (GP) and is followed by P&O in the final stage to achieve a quicker convergence to a GP. Thus, this hybrid algorithm overcomes the computational burden encountered in a standalone WOA, grey wolf optimization (GWO) and hybrid GWO reported in the literature. The conventional algorithm searches for the maximum power point (MPP) in the predicted region by the WOA. The proposed MPPT technique is modelled and simulated using MATLAB/Simulink for simulating an environment to check its effectiveness in accurately tracking the MPP during the GP region. This hybrid algorithm is compared with a standalone WOA, GWO and hybrid GWO. From the simulating results, it is shown that the proposed algorithm offers high tracking performance and that it increases the output power level of a SPV system under partial shading. The algorithm also verified experimentally on various PSCs.
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Nanosized CuO Particles via a Supramolecular Strategy
Premkumar, T.,Geckeler, K. ,E. WILEY-VCH Verlag 2006 Small Vol.2 No.5
<B>Graphic Abstract</B> <P>Uniform cupric oxide nanoparticles have been prepared for the first time via a novel supramolecular complex (see image, left) by thermal decomposition, in which cucurbit[7]uril was selected to encapsulate copper acetate, which acts as the precursor for the CuO nanoparticles (right). The procedure affords particles with a narrow size distribution and of very small diameter (≈5 nm). <img src='wiley_img/16136810-2006-2-5-SMLL200500454-content.gif' alt='wiley_img/16136810-2006-2-5-SMLL200500454-content'> </P>
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Towards maximizing the haze effect of electrodes for high efficiency hybrid tandem solar cell
Vincent, Premkumar,Song, Dong-Seok,Kwon, Hyeok Bin,Kim, Do-Kyung,Jung, Ji-Hoon,Kwon, Jin-Hyuk,Choe, Eunji,Kim, Young-Rae,Kim, Hyeok,Bae, Jin-Hyuk Elsevier 2018 APPLIED SURFACE SCIENCE - Vol.432 No.2
<P><B>Abstract</B></P> <P>In this study, we executed optical simulations to compute the optimum power conversion efficiency (PCE) of a-Si:H/organic photovoltaic (OPV) hybrid tandem solar cell. The maximum ideal short circuit current density (J<SUB>sc,max</SUB>) of the tandem solar cell is initially obtained by optimizing the thickness of the active layer of the OPV subcell for varying thickness of the a-Si:H bottom subcell. To investigate the effect of Haze parameter on the ideal short-circuit current density (J<SUB>sc,ideal</SUB>) of the solar cells, we have varied the haze ratio for the TCO electrode of the a-Si:H subcell in the tandem structure. The haze ratio was obtained for various root mean square (RMS) roughness of the TCO of the front cell. The effect of haze ratio on the J<SUB>sc,ideal</SUB> on the tandem structured solar cell was studied, and the highest J<SUB>sc,ideal</SUB> was obtained at a haze of 55.5% when the thickness of the OPV subcell was 150nm and that of the a-Si:H subcell was 500nm.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Current matching is required to maximize efficiency in tandem solar cells. </LI> <LI> Haze effect helps in trapping the light within the active layer. </LI> <LI> Light scattering due to rough electrode surface helped in current matching by balancing light absorption. </LI> <LI> Simulation shows an improvement in ideal short-circuit current density by 7.6% due to haze effect. </LI> <LI> Active layer thickness combination of 500nm (a-Si:H) and 150nm (OPV) exhibited the best optimized structure. </LI> </UL> </P>
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Indoor-type photovoltaics with organic solar cells through optimal design
Vincent, Premkumar,Shin, Sang-Chul,Goo, Ji Soo,You, Young-Jun,Cho, Boram,Lee, Suwoong,Lee, Dong-Wook,Kwon, Se Ra,Chung, Kwun-Bum,Lee, Jae-Joon,Bae, Jin-Hyuk,Shim, Jae Won,Kim, Hyeok Elsevier 2018 Dyes and pigments Vol.159 No.-
<P><B>Abstract</B></P> <P>Indoor solar cells are an attractive option to install in buildings to harvest the energy emitted by indoor lighting. They can be implemented as a stand-alone grid, or as part of an integrated energy harvesting unit. Previous research has utilized amorphous silicon and dye-sensitized solar cells for power generation from a fluorescent light source. In our study, we evaluated the applicability of a poly (3-hexylthiophene):indene-C60 bisadduct solar cell to harvest the light spectrum from an indoor light-emitting diode (LED). Because the absorption peak of poly (3-hexylthiophene) overlaps the LED spectrum peak, it serves as a good candidate for indoor light harvesting under an LED source. We have extracted the power conversion efficiency of the solar cell under different LED illuminance values, such as 200, 800, 1000, and 2000 lx. With the help of finite-difference time domain simulations, we optimized the solar device structure for each illuminance. The results detailed in this article were intended to assess the applicability of organic solar cells as indoor photovoltaics, and to provide a methodology to optimize the photovoltaic structure to maximize its efficiency.</P>
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