区域电力市场竞价交易结构与模式的探讨

结合我国经济发展的实际情况和电网的运营特点，对发电侧电力市场竞价交易结构与模式、国内外研究现状进行了分析。特别是对区域电力调度交易中心与省电力调度交易中心的职能与职责划分、市场安全稳定运营等提出了建设性意见。同时提出了容量合同与效率优先相结合的竞价交易模式，为区域电力市场的构建提供了新想法。     

考虑机组爬坡速率和网络安全的经济调度新算法

提出了考虑机组出力变化速率、线路潮流约束和断面传输功率约束的经济调度新算法。对机组出力变化速率的2种情况进行了解释。对以微增网流法为基础的该算法的流程进行了详细的分析。用IEEE 24母线系统对算法进行了验证。计算表明，算法对机组出力变化速率、线路潮流约束和断面传输功率约束的处理正确，计算速度快。     

发电市场技术支持系统中的有功安全校正策略

提出了符合中国发电市场运营规则的安全校正策略。考虑了机组出力变化速率约束、线路潮流速率约束和断面潮流速率约束，在灵敏度计算的基础上，以机组出力调整量最小和购电费用增量最小2种目标对机组出力计划进行调整。依据该算法研制开发的应用软件已在浙江发电市场技术支持系统（PMOS-2000）中投入实时运行，实践证明，该算法切实可靠，收敛速度快，鲁棒性强，能够处理实时运行中的各种情况。     

初期电力市场确定电网日发电计划的模型与方法

在日前交易未开放的初期电力市场模式下，如何针对其特点建立合理的日发电计划模型对于保证这一时期各市场参与者的利益具有重要作用。文中立足电网公司建立日发电计划模型，重点考虑了非竞价机组的经济运行成本，并计及了包括竞价机组年度和月度中标电量的日分解值、机组爬坡速度、旋转备用和线路有功传输限制等约束。在所建模型的基础上，通过改进二次规划的可行方向法，计算发电成本函数为分段二次函数的动态优化调度问题，并与一个启发式机组组合算法相结合用以确定日发电计划。算例结果表明，该模型及方法可行、有效。     

分段竞价电力市场的出清算法实现

根据分段竞价的原理，提出了一种具体的分段竞价电力市场的出清算法。考虑将日负荷预测曲线分成基荷、腰荷和峰荷段。它既可以区分1 d中的电能质量，又可以从电能计量上实现，同时与常规的调度概念相近，便于接受。根据电厂的报价曲线，各段按报价从低到高的顺序进行初步安排，安排中考虑了机组的爬坡速度约束。为保证电能同质同价的公平原则，各分段按照各自统一的出清价结算。根据总购电费用最小进行优化调整,即对腰荷段和峰荷段的分界点寻优以使腰荷段和峰荷段购电费用之和最小，最后进一步优化组合基荷机组达到总体的优化方案。对于水电机组，其强迫出力和可调节电量事先在负荷曲线上安排。通过算例系统的计算表明，这种具体的出清算法计算简单，能更好地满足电力运行的条件。     

日前市场下发电商机组优化组合研究

日前电力市场下,发电集团经常面临在给定总负荷出力曲线和总备用服务要求下,如何在机组间(厂间)进行合理分配出力/备用容量的优化问题,针对于此,提出了考虑旋转备用服务的日前市场机组组合模型和"基于决策树的动态规划法"的求解方法,并利用该方法进行了具体实例计算,深入分析了旋转备用被调用概率、结算价格和容量对机组组合模型优化结果的影响,为发电集团合理安排日前市场下机组间(厂间)负荷分配或联合调度营运提供了一定的思路和实际意义。     

分时电价下梯级水电站日优化调度模型的探讨

梯级水电站日优化调度模型在考虑电网负荷要求和梯级水电站各机组的振动区的前提下,采用电网允许的峰平谷负荷比约束日内各时段的出力,达到了减少机组起停次数的目的。模型采用动态定出力求解,以梯级电站发电收入最大化为目标,并用实例对此模型进行了计算。计算过程和结果表明,动态定出力求解时间短,优化结果与目前的电网需求相一致。     

一种水电站厂内经济运行算法

介绍一种将惩罚函数、动态修正出力-流量(N-Q)关系与优化算法相结合实现水电站厂内经济运行的方法。该方法可针对短期优化调度结果(日负荷过程)制定启停计划,实现负荷的经济分配,并且考虑了机组间的效率差异、机组启停成本、气蚀振动区、机组可用性及主接线方式等约束条件。算例表明该方法不仅能解决厂内经济运行的多约束问题,而且能与电力市场下的短期优化调度很好地结合起来。该方法易于实现程序设计且计算速度快。     

考虑多种约束条件的机组组合新算法

提出了考虑系统降出力备用约束、机组出力变化速率、线路潮流约束和断面传输功率约束的机组组合新算法。算法没有引入任何乘子，计算单调收敛，速度快，并且不需要初始可行解。用IEEE 24母线系统对算法进行了验证，结果表明，算法对各种约束条件的处理正确，解的质量好。     

区域电力市场竞价交易模型与交易机制的研究:（一）竞价交易模型及其机理、水电参与市场竞价的模式及电网安全校核机制

在设计区域电力市场的竞价模式和规则时，必须考虑资源优化配置与资源公平配置的有效协调，坚持做到公开、公正、公平的“三公”原则，努力实现各方利益的平衡协调，同时还要充分考虑如何保证电网的安全稳定运行，努力实现市场交易与电网调度的有效配合。基于上述理念，文中深入分析研究了影响中国区域电力市场竞价机制的因素、区域电力市场竞价的目标模式选择、区域电力市场竞价交易模型与竞价交易机理及水电参与市场竞价的模式，提出了兼顾电网调度、电网安全稳定运行与市场交易相协调的区域电力市场竞价交易模型及电网安全校核机制。     

Call for Papers

正As the eldest and most distributed professional journal of water industry,Water Wastewater Engineering(W WE)gained very wide acceptance from the colleagues working in this field in this country since start publication in 1964.Now it is administrated by the Ministry of Construction of the People’s Republic of China and sponsored by the China Civil Engineering Society etc.     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Serial discontinuities in a Rocky mountain river. I. Distribution and abundance of plecoptera

Samples were taken year-round at eleven sites along the altitudinal profile (2900-1400 m a.s.l.) of the Gunnison River, a 329 km tributary of the Colorado River, to document the distribution of the Plecoptera and to evaluate responses to hypolimnial-release dams in the headwaters and middle reaches. Twenty-two species were present, with the greatest species richness occurring in an unregulated segment upstream of the middle reach dams; average nymphal biomass over the study period (175 organisms, 395 mg dry mass m^?2) was also greatest in this segment. Only four species (58 organisms, 48 mg m^?2) were present in the tailwaters of the headwater dam and values were greatly reduced (nine species; 35 organisms, 180 mg m^?2) below the middle reach dams. The stonefly community recovered ca. 80 km downstream from the last dam (15 species; 244 organisms, 250 mg m^?2), apparently in response to natural resetting of environmental conditions corresponding to those above the middle reach dams. At the most downstream site (11) only four species (four organisms, 16 mg m^?2) were present. The observed distributional pattern is a classic serial discontinuity in response to hypolimnial stream regulation in a temperate latitude river.     

Impacts of Microcystis on algal biodiversity and use of new technology to remove Microcystis and dissolved nutrients

Cyanobacteria often dominate eutrophic lakes, outcompeting green algae that are required by fish and zooplankton. This study was undertaken to ascertain the impact of the cyanobacterium, Microcystis, on algal biodiversity. Under laboratory conditions, we found that the presence of Microcystis decreased phyla richness by 58%, phyla evenness by 47%, genera richness by 66% and genera evenness by 51%. Analysis by mixed anova s demonstrated a significant interaction between treatment and time and confirmed a significant reduction in richness and evenness of phyla and genera. We also conducted a phosphate restriction assay on the algae in Mason Lake (Irvine, CA, USA) and found that the threshold needed for algal growth there was 0.02 mg L^?1 PO₄. A pilot study was then conducted to test the effectiveness of the Blue Pro? water treatment facility in removal of this colonial organism from Mason Lake, in addition to removal of dissolved nutrients required for its growth. We measured a 97% reduction in Microcystis cells, a 72% reduction in chlorophyll‐a, and a 96% reduction in phosphate after just one 10 min cycle through the unit. Our study demonstrated that removal of Microcystis colonies may allow green algae to increase in numbers. This may improve algal biodiversity, which will benefit zooplankton and fishes.     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

库水波动下库岸边坡地下水浸润线解析解及误差分析

解析法是库岸边坡地下水浸润线计算中便于实际应用的方法,但该方法须基于若干假定并对潜水运动基本方程线性化后才能求解。针对各假定和线性化过程建立不同的地下水渗流数学模型,用解析法和有限元法解答上述数学模型,分析各误差大小及其规律。结果表明：库岸垂直处理带来的误差要小于方程线性化处理和不考虑非饱和渗流带来的误差,而且它们都随渗透系数变大而减小;在三峡库区库水调度情况下,假定库水位等速变化带来的误差对大多岸坡而言可以忽略;计算库岸边坡地下水浸润线时,解析法只适用于水位变化幅度相比含水层厚度较小,且几何边界规则、岩土结构简单、岩土体渗透性较好时的情况。     

SPATIAL AND TEMPORAL WATER QUALITY VARIABILITY IN AQUATIC HABITATS OF A CULTIVATED FLOODPLAIN

The floodplains of lowland rivers contain diverse aquatic habitats that provide valuable ecosystem services but are perturbed when intensively cultivated. Hydrologic, water chemistry and biological (fish) conditions in five aquatic habitats along the Coldwater River, Mississippi, were measured for more than 4 years: the river, two severed meanders that functioned as backwaters, a managed wetland and an ephemeral channel draining cultivated fields. Off‐channel habitats were connected to downstream regions 0.10% to 32% of the dry season and 24% to 67% of the wet season. The median temperatures for the five monitored sites ranged from 18°C to 23°C, the median total solids concentration for all sites was 135 mg L^?1, the median total phosphorus was 0.29 mg L^?1 and the median total nitrogen was 1.56 mg L^?1. Chemical and physical water quality displayed strong seasonal differences between the wet winter/spring and the dry summer/fall periods so that temporal variation consisted of gradual seasonal trends superimposed on strong diurnal variations. All off‐channel habitats exhibited periods of hypoxia and temperatures >30°C during the dry season. Between‐site gradients of water and habitat quality were strongly coupled to water depth and runoff loading. The rehabilitation of one backwater by increasing water depth and diverting agricultural runoff was associated with improved water quality and fish species richness relative to an adjacent untreated backwater. The diversion of polluted runoff and the use of water control structures to maintain greater water depth were observed to be effective management tools, but the former reduces the water supply to habitats that tend to dry up and the latter reduces connectivity. Published in 2011 by John Wiley & Sons, Ltd.     

Changes in Summer Irrigated Crop Area and Water Use in Southeastern Turkey from 1993 to 2002: Implications for Current and Future Water Resources

Changes in summer irrigated cropland acreage and related water use are estimated from satellite remote sensing and ancillary data in semi-arid Southeastern Turkey where traditionally dry agricultural lands are being rapidly transformed into irrigated fields with the help of water from the Euphrates-Tigris Rivers. An image classification methodology based on thresholding of Landsat NDVI images from the peak summer period reveals that the total area of summer irrigated crops has increased three-fold (from 35,000 ha to over 100,000) in the Harran Plain between 1993 and 2002. Coupled analysis of annual irrigated crop area from remote sensing and potential evapotranspiration based estimates of irrigation water requirements for cotton indicate a corresponding increase in agricultural water use from about 370 million cubic meters to over one billion cubic meters, a volume in accordance with the state estimates. These estimates have important implications for understanding the rapid changes in current agricultural withdrawals in Southeastern Turkey and form a quantitative basis for exploring the changes in future water demands in the region. For example, expansion of irrigated lands have led to a steady decrease in potential evaporation due to increased roughness and decreased humidity deficit in the Harran Plain. Assuming that the changes in future evaporation conditions will be of similar nature, water use for irrigation is expected to decrease over 40 percent in future irrigation sites. Incorporating this decrease in overall planning of the irrigation projects currently under construction should lead to improved management, and by extension, sustainability of water resources in the region.     

簸箕李引黄灌区水沙分布及优化调度的经验

灌区利用水沙观测所取得的资料和试验数据，运用水沙运动力学理论，总结分析和揭示了灌区水沙分布的规律和特点。在此基础上，结合灌区的实际运行情况，围绕减少骨干渠道的淤积进行探讨、研究，进而，优化水沙调度方案。该方案实施后，骨干渠道减旅伴效果明显，取得了成功的经验。