分析了两种最大功率追踪(MPPT)的方法:扰动观察法(Perturbation and Observation,P&O)与功率反馈法。利用仿真模拟并评估了两种方法的性能,二者功率追踪精确性都可以达到99%以上,但是不同的追踪手段会在追踪时间、系统稳定性、实现...分析了两种最大功率追踪(MPPT)的方法:扰动观察法(Perturbation and Observation,P&O)与功率反馈法。利用仿真模拟并评估了两种方法的性能,二者功率追踪精确性都可以达到99%以上,但是不同的追踪手段会在追踪时间、系统稳定性、实现成本等方面产生不同的影响。本文旨在仿真结果的基础上,对上述问题进行分析与优化。展开更多
A novel three-phase active power filter （APF） circuit with photovoltaic （PV） system to improve the quality of service and to reduce the capacity of energy storage capacitor is presented. The energy balance concept...A novel three-phase active power filter （APF） circuit with photovoltaic （PV） system to improve the quality of service and to reduce the capacity of energy storage capacitor is presented. The energy balance concept and sampling technique were used to simplify the calculation algorithm for the required utility source current and to control the voltage of the energy storage capacitor. The feasibility was verified by using the Pspice simulations and experiments. When the APF mode was used during non-operational period, not only the utilization rate, power factor and power quality could be improved, but also the capacity of energy storage capacitor could sparing. As the results, the advantages of the APF circuit are simplicity of control circuits, low cost, and good transient response.展开更多
This paper presents the outdoor performance evaluation of different grid-connected PV technologies installed in Cyprus over a two year period. The PV research and testing facility at the University of Cyprus was commi...This paper presents the outdoor performance evaluation of different grid-connected PV technologies installed in Cyprus over a two year period. The PV research and testing facility at the University of Cyprus was commissioned in 2006 to perform continuous measurements of meteorological and PV operational parameters. The test site is appropriately equipped to undertake such evaluations at a very high resolution （1 measurement per second）. The perfromance results obtained for the two year evaluation period clearly show how each PV technology has performed under the climatological conditions in Cyprus. Finally the high average energy yield of the fixed plate systems under test, 1580 kWh/kWp and 1609 kWh/kWp during the first and second year of evaluation respectively, also verifies that solar energy is a very promising renewable source of energy for countries with a high solar resource.展开更多
Reducing energy loss(V_(loss))is one of the most crucial challenges in organic photovoltaic cells.The V_(loss),determined by the differences between the optical band gap(E_(g))of the active layer material and the open...Reducing energy loss(V_(loss))is one of the most crucial challenges in organic photovoltaic cells.The V_(loss),determined by the differences between the optical band gap(E_(g))of the active layer material and the open-circuit voltage(V_(oc))of the device,is generally alleviated by lowering the energy difference between the lowest unoccupied molecular orbital(LUMO)and highest occupied molecular orbital(HOMO)level of the donor(D)and acceptor(A).In this work,we synthesized two A-π-D-π-A-type small-molecule donors(SMDs)SM-benzotriazole(BTz)-1 and SM-BTz-2 by introducing a BTzπ-bridge unit and terminal regulation.The BTzπ-bridge unit significantly lowers the HOMO energy level of SMDs,resulting in high V_(oc)and high mobility,achieving a balance of low energy loss(<0.5 eV)and high efficiency.Ultimately,the organic solar cells based on SM-BTz-2 as the donor and Y6 as the acceptor obtain a high V_(oc)of 0.91 V,J_(sc) of 22.8 mA cm^(−2),fill factor of 68%,and power conversion efficiency(PCE)of 14.12%,which is one of the highest efficiencies based on the SMDs with triazoleπ-bridges to date.What’s more,the BTzπ-bridge unit is a potential unit that can improve mobility and reduce energy loss.展开更多
Over the years,the efficiency of inorganic perovskite solar cells(PSCs)has increased at an unprecedented pace.However,energy loss in the device has limited a further increase in efficiency and commercialization.In thi...Over the years,the efficiency of inorganic perovskite solar cells(PSCs)has increased at an unprecedented pace.However,energy loss in the device has limited a further increase in efficiency and commercialization.In this work,we used(NH4)2C2O4·H2O to treat CsPbBrI2 perovskite film during spin-coating.The CsPbBrI2 underwent secondary crystallization to form high quality films with micrometer-scale and low trap density.(NH4)2C2O4·H2O treatment promoted charge transfer capacity and reduced the ideal factor.It also dropped the energy loss from 0.80 to 0.64 eV.The resulting device delivered a power conversion efficiency(PCE)of 16.55%with an open-circuit voltage(Voc)of 1.24 V,which are largely improved compared with the reference device which exhibited a PCE of 13.27%and a Voc of 1.10 V.In addition,the optimized treated device presented a record indoor PCE of 28.48%under a fluorescent lamp of 1000 lux,better than that of the reference device(19.05%).展开更多
The properties of Al-doped Zn O(AZO) play an important role in the photovoltaic performance of inverted polymer solar cells(PSCs), which is used as electron transport and hole blocking buffer layers. In this work, we ...The properties of Al-doped Zn O(AZO) play an important role in the photovoltaic performance of inverted polymer solar cells(PSCs), which is used as electron transport and hole blocking buffer layers. In this work, we study the effects of Al-doping level in AZO on device performance in detail. Results indicate that the device performance intensely depends on the Al-doping level. The AZO thin films with Al-doping atomic percentage of 1.0% possess the best conductivity. The resulting solar cells show the enhanced short current density and the fill factor(FF) simultaneously, and the power conversion efficiency(PCE) is improved by 74%, which are attributed to the reduced carrier recombination and the optimized charge transport and extraction between AZO and the active layer.展开更多
文摘分析了两种最大功率追踪(MPPT)的方法:扰动观察法(Perturbation and Observation,P&O)与功率反馈法。利用仿真模拟并评估了两种方法的性能,二者功率追踪精确性都可以达到99%以上,但是不同的追踪手段会在追踪时间、系统稳定性、实现成本等方面产生不同的影响。本文旨在仿真结果的基础上,对上述问题进行分析与优化。
文摘A novel three-phase active power filter （APF） circuit with photovoltaic （PV） system to improve the quality of service and to reduce the capacity of energy storage capacitor is presented. The energy balance concept and sampling technique were used to simplify the calculation algorithm for the required utility source current and to control the voltage of the energy storage capacitor. The feasibility was verified by using the Pspice simulations and experiments. When the APF mode was used during non-operational period, not only the utilization rate, power factor and power quality could be improved, but also the capacity of energy storage capacitor could sparing. As the results, the advantages of the APF circuit are simplicity of control circuits, low cost, and good transient response.
文摘This paper presents the outdoor performance evaluation of different grid-connected PV technologies installed in Cyprus over a two year period. The PV research and testing facility at the University of Cyprus was commissioned in 2006 to perform continuous measurements of meteorological and PV operational parameters. The test site is appropriately equipped to undertake such evaluations at a very high resolution （1 measurement per second）. The perfromance results obtained for the two year evaluation period clearly show how each PV technology has performed under the climatological conditions in Cyprus. Finally the high average energy yield of the fixed plate systems under test, 1580 kWh/kWp and 1609 kWh/kWp during the first and second year of evaluation respectively, also verifies that solar energy is a very promising renewable source of energy for countries with a high solar resource.
基金the National Key Research and Development Program of China(2019YFA0705900)the National Natural Science Foundation of China(51820105003,21734008,61904181,52173188 and 52103243)+1 种基金the Key Research Program of the Chinese Academy of Sciences(XDPB13)the Basic and Applied Basic Research Major Program of Guangdong Province(2019B030302007).
文摘Reducing energy loss(V_(loss))is one of the most crucial challenges in organic photovoltaic cells.The V_(loss),determined by the differences between the optical band gap(E_(g))of the active layer material and the open-circuit voltage(V_(oc))of the device,is generally alleviated by lowering the energy difference between the lowest unoccupied molecular orbital(LUMO)and highest occupied molecular orbital(HOMO)level of the donor(D)and acceptor(A).In this work,we synthesized two A-π-D-π-A-type small-molecule donors(SMDs)SM-benzotriazole(BTz)-1 and SM-BTz-2 by introducing a BTzπ-bridge unit and terminal regulation.The BTzπ-bridge unit significantly lowers the HOMO energy level of SMDs,resulting in high V_(oc)and high mobility,achieving a balance of low energy loss(<0.5 eV)and high efficiency.Ultimately,the organic solar cells based on SM-BTz-2 as the donor and Y6 as the acceptor obtain a high V_(oc)of 0.91 V,J_(sc) of 22.8 mA cm^(−2),fill factor of 68%,and power conversion efficiency(PCE)of 14.12%,which is one of the highest efficiencies based on the SMDs with triazoleπ-bridges to date.What’s more,the BTzπ-bridge unit is a potential unit that can improve mobility and reduce energy loss.
基金financial support from the National Key R&D Program of China(2016YFA0202400)the National Natural Science Foundation of China(61674109)+4 种基金the Natural Science Foundation of Jiangsu Province(BK20170059)funded by the Collaborative Innovation Center of Suzhou Nano Science and Technologythe Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the “111”Project of The State Administration of Foreign Experts Affairs of Chinathe Open Fund of the State Key Laboratory of Integrated Optoelectronics(IOSKL2018KF07)。
文摘Over the years,the efficiency of inorganic perovskite solar cells(PSCs)has increased at an unprecedented pace.However,energy loss in the device has limited a further increase in efficiency and commercialization.In this work,we used(NH4)2C2O4·H2O to treat CsPbBrI2 perovskite film during spin-coating.The CsPbBrI2 underwent secondary crystallization to form high quality films with micrometer-scale and low trap density.(NH4)2C2O4·H2O treatment promoted charge transfer capacity and reduced the ideal factor.It also dropped the energy loss from 0.80 to 0.64 eV.The resulting device delivered a power conversion efficiency(PCE)of 16.55%with an open-circuit voltage(Voc)of 1.24 V,which are largely improved compared with the reference device which exhibited a PCE of 13.27%and a Voc of 1.10 V.In addition,the optimized treated device presented a record indoor PCE of 28.48%under a fluorescent lamp of 1000 lux,better than that of the reference device(19.05%).
基金supported by the National Natural Science Foundation of China(No.61377031)the Scientific Research Foundation of Zhejiang Ocean University(No.Q1444)
文摘The properties of Al-doped Zn O(AZO) play an important role in the photovoltaic performance of inverted polymer solar cells(PSCs), which is used as electron transport and hole blocking buffer layers. In this work, we study the effects of Al-doping level in AZO on device performance in detail. Results indicate that the device performance intensely depends on the Al-doping level. The AZO thin films with Al-doping atomic percentage of 1.0% possess the best conductivity. The resulting solar cells show the enhanced short current density and the fill factor(FF) simultaneously, and the power conversion efficiency(PCE) is improved by 74%, which are attributed to the reduced carrier recombination and the optimized charge transport and extraction between AZO and the active layer.
