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991.
This study was interested in the management of an energy production unit. A variable speed wind turbine (VSWT) was used as a principal source and a supercapacitor (SC) module was used as an energy storage system. Both were connected through a direct current bus. This unit was supplying a three-phase load using an inverter and an inductor and capacitor filter. In order to regulate the direct current bus voltage, the SC storage state was controlled by using a buck-boost converter according to load instructions and wind speed fluctuations. Then, a resonant controller was established to avoid any disturbances and to control the alternating line-to-line voltages of the load which may be unbalanced. This study has shown that the stability of the three-phase voltage source depends on the direct current bus power management and also on the line-to-line voltage control. Simulation results are presented to validate the efficiency of the control strategies used. 相似文献
992.
Baltasar Peñate Fernando CastellanoAlejandro Bello Lourdes García-Rodríguez 《Energy》2011,36(7):4372-4384
Desalination driven by renewable energies is an interesting technology in isolated coastal areas. Its feasibility and reliability are guaranteed by innumerable designs implemented and experiences carried out, mainly focused on small capacity systems. However, only mature and efficient technologies are suitable for medium or large scale desalination. In the case of seawater desalination, wind-powered reverse osmosis is the most efficient, mature and cost-effective technology. This paper assesses the most suitable design for seawater reverse osmosis desalination driven by off-grid wind energy systems. A high innovative design based on gradual capacity with nominal production of 1000 m3/d is compared to a conventional fixed capacity desalination plant. Due to the intermittent wind resource, the gradual capacity desalination plant is able to fit the available energy and maximize the annual water production. 相似文献
993.
Yu Chen Fanglin ChenWendong Wang Dong DingJianfeng Gao 《Journal of power sources》2011,196(11):4987-4991
Sm0.2(Ce1−xTix)0.8O1.9 (SCTx, x = 0-0.29) modified Ni-yttria-stabilized zirconia (YSZ) has been fabricated and evaluated as anode in solid oxide fuel cells for direct utilization of methane fuel. It has been found that both the amount of Ti-doping and the SCTx loading level in the anode have substantial effect on the electrochemical activity for methane oxidation. Optimal anode performance for methane oxidation has been obtained for Sm0.2(Ce0.83Ti0.17)0.8O1.9 (SCT0.17) modified Ni-YSZ anode with SCT0.17 loading of about 241 mg cm−2 resulted from four repeated impregnation cycles. When operating on humidified methane as fuel and ambient air as oxidant at 700 °C, single cells with the configuration of SCT0.17 modified Ni-YSZ anode, YSZ electrolyte and La0.6Sr0.4Co0.2Fe0.8O3-Sm0.2Ce0.8O1.9 (LSCF-SDC) composite cathode show the polarization cell resistance of 0.63 Ω cm2 under open circuit conditions and produce a peak power density of 383 mW cm−2. It has been revealed that the coated Ti-doped SDC on Ni-YSZ anode not only effectively prevents the methane fuel from directly impacting on the Ni particles, but also enhances the kinetics of methane oxidation due to an improved oxygen storage capacity (OSC) and redox equilibrium of the anode surface, resulting in significant enhancement of the SCTx modified Ni-YSZ anode for direct methane oxidation. 相似文献
994.
Jia MaNurul A. Choudhury Yogeshwar Sahai Rudolph G. Buchheit 《Journal of power sources》2011,196(20):8257-8264
A cross-linked chitosan (CCS) membrane has been prepared by a solution casting method using sulfuric acid as cross-linking agent. The CCS membrane was used as the polymer electrolyte and separator in a direct borohydride fuel cell (DBFC). Ionic conductivity and borohydride crossover rate have been measured for the CCS membrane. The DBFC used in this study employed nickel-based composite as anode catalyst and Nafion® as anode binder. The power performance of the CCS membrane-based DBFC was compared with a similar DBFC employing Nafion® 212 (N212) membrane as electrolyte /separator. The CCS membrane-based DBFC exhibited better power performance as compared to N212 membrane-based DBFC. Encouraged by this result, chitosan chemical hydrogel (CCH) was prepared and used as binder for anode catalysts. A DBFC comprising CCS membrane and CCH as anode binder was studied and found to exhibit even better power performance at all temperatures in this study. A maximum peak power density of 450 mW cm−2 was observed at 60 ?C for DBFC employing CCS membrane and CCH binder-based anode. The chitosan-based DBFC was operated continuously for 100 h and its performance stability was recorded. 相似文献
995.
Although zeolites are introduced to decrease methanol crossover of Nafion membranes for direct methanol fuel cells (DMFCs), little is known about the effect of their intrinsic properties and the interaction with the ionomer. In this work, Nafion-Faujasite composite membranes prepared by solution casting were characterized by extensive physicochemical and electrochemical techniques. Faujasite was found to undergo severe dealumination during the membrane activation, but its structure remained intact. The zeolite interacts with Nafion probably through hydrogen bonding between Si-OH and SO3H groups, which combined with the increase of the water uptake and the water mobility, and the addition of a less conductive phase (the zeolite) leads to an optimum proton conductivity between 0.98 and 2 wt% of zeolite. Hot pressing the membranes before their assembling with the electrodes enhanced the DMFC performance by reducing the methanol crossover and the serial resistance. 相似文献
996.
"超滤+反渗透+EDI"的全膜法工艺应用了最新的膜分离技术来制备锅炉补给水,超滤良好的产水水质能够给反渗透膜提供最佳的保护,而替代传统混床的电除盐(EDI)技术则彻底消除了酸碱的使用和废水排放。但因各地水源不同,该系统在运行过程中也存在一定的缺陷,应根据各地水源的不同作相应的改造,经改造后的系统在热电厂的实际运行结果表明,系统运行可靠,管理方便,产水水质完全能够满足锅炉用水要求。 相似文献
997.
纳滤膜在北京阿苏卫填埋场渗滤液改扩建工程中的应用 总被引:2,自引:0,他引:2
在阿苏卫垃圾卫生填埋场渗滤液改扩建工程中,以膜生物反应器(MBR)的出水为研究对象,考察了在一定的pH、进水流量、操作压力下纳滤膜对CODcr、NH3-N和电导率的去除情况.结果表明:在设备初期运行阶段,在pH为7、操作压力为0.5 MPa时,纳滤膜对CODcr的去除率达75%;对NH3-N的去除率较低,出水的NH3-N值略低于进水;对电导率的平均去除率达55%.此外,还分析了纳滤膜的运行性能以及与原有反渗透处理工艺联合使用等问题. 相似文献
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