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1.
新型市电互补光伏系统采用不同于传统市电互补光伏系统的设计方案,解决传统光伏系统易损坏、维修麻烦、连续阴雨天无法正常供电等问题。新型市电互补光伏系统能够按照负载的实际需求在市电电源和光伏电源之间切换,能让蓄电池得以充分充电和养护。新型市电互补光伏系统不仅工作更加可靠,还可以减少蓄电池的更换次数,降低蓄电池的使用量,进而降低投资费用。  相似文献   

2.
设计了一套低成本、智能化的以STC89C52单片机作为主控制器的UPS系统。通过该单片机对市电异常电压进行监测,控制转换开关执行电网电力与蓄电池供电的切换,对蓄电池电压电流大小进行判断,完成对蓄电池恒流、恒压和浮充充电智能化充电管理。通过实验测试,对UPS输出电压进行了谐波分析,设计的系统不仅可以提高蓄电池的充电效率,还能有效地延长蓄电池的使用寿命,系统运行稳定可靠、成本低,电网与UPS系统供电切换快速可靠。  相似文献   

3.
周彦 《科技咨询导报》2011,(31):103-104
本文提出了一种可减少这种损失的应急不间断电源。对三相在线式不间断电源的工作原理进行了系统的分析,其基本工作原理为:当市电正常时,负载由市电供电;当市电异常时,负载由蓄电池供电。主电路由双向PWM电路、双向DC/DC电路、蓄电池和滤波电路等组成,通过分析它们的电路结构、工作原理、设计和控制策略,阐述了它们在UPS电路中的应用。本系统具有功率因数较高,启动时间短,应急速度快,无噪声,维护简单,可以无人值守等优点。  相似文献   

4.
本文通过对甘德站CAWS600自动气象站供电系统的改造,从而彻底解决了该站存在的供电问题。利用以前单边带电台退役设备,并购买太阳能电池板和电子元件等建成了一个集市电供电、太阳能供电及油机供电三位一体的小型太阳能供电系统,此工程能为其他无市电或市电不正常的一般站提供一个借鉴的经验。  相似文献   

5.
惠力  赵杰  鲁成杰 《山东科学》2011,24(3):51-54
为保证海洋仪器太阳能供电系统的连续稳定运行,采用了一种基于能量守恒的简易计算方法,计算太阳能电池板功率和蓄电池容量等参数,设计的太阳能供电系统在实际应用过程中可以很好地满足仪器供电要求。  相似文献   

6.
徐璇  曹会国 《科技信息》2013,(19):39-40
设计了一种简易多功能太阳能手机充电系统。可以直接利用太阳能充电系统对手机充电;也可利用太阳能充电系统或市电对用蓄电池供电,存储电能,必要时用来对手机充电。系统能保证手机在各种条件下正常充电,最大限度利用太阳能,实现能源绿色化。  相似文献   

7.
给出了"太阳能电池板、蓄电池、充电控制器和电压变换与监测" 的太阳能供电系统的设计结构.详细计算了系统中各个组成模块的技术参数,并以此选取了单晶硅太阳能电池板、免维护铅酸电池和智能充电控制器,设计了电压变换和电压监测电路.现场试验和应用表明,设计的12V/20Wp太阳能供电系统满足胜利油田(东营地区)连续3个阴雨天条件下无线小型录井仪的连续供电要求,工作稳定.  相似文献   

8.
针对昆明地区户用光伏交流冰箱系统的工作特性进行了实验研究,在不同天气条件下对所构建的系统性能进行了测试,测试结果表明,该系统冰箱的冷冻室最低温度可达-22℃,冷藏室温度为0~7℃,在晴天和多云天气情况下,系统带3kg水时制冷系数COP分别为0.08、0.05,系统带8kg负载时制冷系数COP分别为0.28、0.23;在阴雨天气情况下,蓄电池单独向系统供电可保证系统连续工作3d.该光伏冰箱系统在昆明地区运行稳定,并为户用光伏交流冰箱系统性能的进一步优化提供了依据.  相似文献   

9.
以太阳能光伏冷库系统为研究对象,采用5.4 kW分布式太阳能光伏发电为动力源直接驱动压缩机制冰蓄冷,对系统在市电与光伏协同模式下连续一周的运行特性相关参数进行了实验.在市电-光伏的协同工作模式下,白天平均制冷量为56.48 MJ,平均储冰量为118.56 kg,夜间冷库系统的平均耗冷量为34.77 MJ,对应的平均耗冰量为99.27 kg;光伏直驱连续运行模式下系统平均制冷性能系数(COP_(ref))达到0.83,系统实现了维持5℃果蔬冷藏温度的连续稳定供冷运行.  相似文献   

10.
根据现阶段能源趋势设计了一种供电装置,控制以太阳能发电为主要能源,辅以蓄电池和市电的供电平台正常工作。该装置具有电源切换功能以实现对负载的不间断供电,能够输出稳定的直流电;并能向蓄电池进行三段充电。经过Pspice软件仿真表明蓄电池充电模块及恒压输出模块能够达到设计要求输出的电压电流值。控制电路通过Proteus软件仿真能够实现电源的切换及蓄电池充电模块的选择功能。该供电装置具有较高的可靠性;并能够满足多种场合的应用要求。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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