共查询到20条相似文献,搜索用时 62 毫秒
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智能型太阳能跟踪系统设计与实现 总被引:5,自引:0,他引:5
在主动式跟踪太阳能热发电系统中,要求计算太阳位置以实现跟踪,提高发电效率。对于开环控制的太阳能跟踪系统,太阳位置的计算精度尤为重要。采用水平-俯仰双轴坐标系统,利用32位ARM (advanced RISC machine)公司的嵌入式微处理器,以步进电机作为执行机构,提出了基于程控跟踪和光电跟踪相结合的复合跟踪方式,并采用基于J2000.0为基准历元的太阳位置计算系统,减小了计算误差,提高了跟踪精度。该跟踪装置是一种能根据不同地理位置和时间自动计算太阳运行参数,通过光电检测构成反馈回路,实现在不同环境下自动跟踪的智能型跟踪装置。 相似文献
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Nedal Al-Ababneh 《Electrical Engineering (Archiv fur Elektrotechnik)》2007,89(6):451-456
The capacity of free space optical interconnects (FSOIs) is analyzed. The interconnect capacity is expressed as a function
of signal-to-noise ratio (SNR), optical transmitted power, optical received power, optical crosstalk noise power, thermal
noise, and detector size and spacing. The dependence of interconnects capacity on SNR and on feature parameters of photo-detectors
array (fill factor, detectors spacing) is simulated. It is shown that feature parameters of photo-detectors array can be used
as design parameters to optimize and improve the interconnect capacity. The effect of increasing the power budget as far as
possible to improve the interconnect capacity is investigated as well. 相似文献
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《IEEE journal of selected topics in quantum electronics》2008,14(6):1441-1447
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P. Lindskog L. Ljung 《International Journal of Adaptive Control and Signal Processing》1995,9(6):509-523
Semiphysical modelling is often interpreted as an application of system identification where physical insight into the application is used to come up with suitable non-linear transformations of the raw measurements so as to allow for a good model structure. This modelling procedure is less ‘ambitious’ than those used for traditional physical modelling in that no complete physical structure is sought, just suitable inputs and outputs that can be subjected to more or less standard model structures such as linear regressions. In this paper we discuss a semiphysical modelling procedure and various tools supporting it. These include constructive algorithms originating from commutative and differential algebra as well as more informal tools such as the programming environment. 相似文献
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Prieto G. Prieto O. Gay C.R. Yamamoto T. 《Industry Applications, IEEE Transactions on》2003,39(1):72-78
Methyl bromide is amply used as a fumigant for soil conditioning in greenhouses, as well as for storage grain conditioning. The treatment is carried out in a confined place, and after treatment the residual gas is vented to the atmosphere. Despite this gas being very toxic, it does not result in harm to human beings because it is vented in open places. However, it is harmful to the atmosphere because its reaction with high-energy photons in the stratosphere reduces the ozone concentration. Therefore, the present investigation is concerned with the study of the feasibility for destruction of the residual fumigant. One of the nonthermal plasma techniques, a packed-bed ferroelectric reactor, was applied for destruction of mixtures of methyl bromide in nitrogen or air. The performance of the process was studied by analyzing the influence and effect of the operating variables on the process efficiency. The results obtained showed the residence time and the applied voltage as the most significant variables. When nitrogen is employed as the carrier gas destruction efficiencies as high as 80% are obtained. 相似文献
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The objective of this article is to uncover as much as possible the origins and development of magnetobiology. The use of magnetobiology as a diagnostic tool and the technology associated with it such as biomedical MRI and magnetic source imaging are presented. Biomagnetism wherein excitable tissues are regarded as true generators of magnetic fields is also discussed. 相似文献
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基于模糊隶属函数的变压器色谱峰定性算法 总被引:1,自引:0,他引:1
把模糊技术引入了电力变压器色谱峰定性领域。该算法为:把要定性的色谱峰位作为模糊矢量,把各个成分作为模糊集元素,峰位相对于成分的隶属度函数用成分的绝对保留时间来构造,不失一般性,隶属度函数的形状取为三角形,2个相邻成分绝对保留时间中点的隶属度值设为50%,若某个峰位相对于某个成分的隶属度函数值大于50%,则这个峰位就是所用隶属度函数的那个成分的峰位,若存在多个峰位隶属于某个成分,则隶属度最大的那个峰位是相应成分的峰位,其余是假峰。对该算法进行了测试,结果表明:该算法方法简单,抗峰漂移性能良好,可以剔除假峰,具有显著的优点。 相似文献
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New quick-response and high-efficiency control of an induction motor, which is quite different from that of the field-oriented control is proposed. The most obvious differences between the two are as follows. 1) The proposed scheme is based on limit cycle control of both flux and torque using optimum PWM output voltage; a switching table is employed for selecting the optimum inverter output voltage vectors so as to attain as fast a torque response, as low an inverter switching frequency, and as low harmonic losses as possible. 2) The efficiency optimization in the steady-state operation is also considered; it can be achieved by controlling the amplitude of the flux in accordance with the torque command. To verify the feasibility of this scheme, experimentation, simulation, and comparison with field-oriented control are carried out. The results prove the excellent characteristics for torque response and efficiency, which confirm the validity of this control scheme. 相似文献
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分析了采用最大3d平均负荷指标对电网运行的经济性和必要性.随着国内电力供需矛盾趋缓,采用最大3d平均负荷作为电网最大负荷的时机已趋成熟,应参照日本等国的经验,尽早采纳该方法. 相似文献
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《Engineering & Technology》2009,4(4):52-55
What is happiness? One thing is for sure, it certainly is not complete plenitude. Imagine a world where there was no shortage of energy: where you could drive as far and as fast as you wanted at no cost, and could use as many appliances as you asked for and for as long as you wished. The total empowerment that would arise from that would be sickening. 相似文献
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本设计主要采用低功耗高性能的STM32单片机作为微型控制器,采用电压互感器、电流互感器作为变压器的信号转换及电压-电流信号采集模块,采用AD637转换芯片作为信号转换器件,采用过零比较器及异或门电路实现功率因数及信号频率的测量,采用Pt100铂热电阻测温传感器作为变压器绕组的温度采集模块,采用蜂鸣器作为信号故障报警模块,采用WINCC软件组建的触摸屏作为系统的监控界面。系统的主要目的是通过变压器的温度、电参数(电压、电流、功率因数及频率)及外部环境参数的采集实现对变压器参数的检测与监控功能,并根据其采集的参数,确定变压器是否处于正常运行状态。 相似文献
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一种新型固态短路限流器拓扑及其控制策略 总被引:20,自引:8,他引:12
介绍一种适用于中高压电网的新型固态短路故障限流器,正常工作时对线路几乎无影响;当故障发生时,旁路交流电抗器立即自动插入故障回路进行限流,检测到故障后将故障相桥路进行逆变,直流电抗器中的能量回馈电网,桥路尽快退出故障线路的运行,随后故障电流完全由旁路交流电抗器限制。新型限流器的固态器件和直流电抗参数不受电网允许的短路电流水平约束,所以可进行灵活优化设计。理论分析和单相固态限流器在三相系统中的仿真结果表明,整个单相桥路相当于过零点断开的开关,限流器不会引起附加振荡和过电压,控制方法简单,新型固态限流器具有良好特性,在电力系统中有深入研究和开发的意义。 相似文献