330kV安南双回线主保护拒动问题分析

３３０ｋＶ安（康）南（郊）同杆架设双回线是装机容量为８００ＭＷ的安康水电站的主要外送线路。由于安康电站的水库较小，为不完全年调节，枯水季节全厂停机备用时间很多。全厂停机情况下，安南双回线就处在单侧电源方式下，线路的两套主保护将发生拒动。本文对拒动问题进行了分析，并提出了建议。     

计及气象可达性的海上风电运维效益仿真方法

为改善海上风电传统经济评价方法的局限性，根据气象条件等因素对海上风电运维的影响，分析计及气象可达性的海上风电运维流程，提出涵盖停机时间、损失电量、风电场可利用率和运维成本等经济评价指标计算方法，建立基于Anylogic平台的海上风电运维效益仿真模型，模拟风电机组、船舶、人员实时状态，统计各项经济评价指标，评估海上风电场运维经济效益。案例结果表明：所建立的效益仿真模型可模拟风电场的运维流程，并较为准确地推算出停机时间、损失电量、风电场可利用率及运维成本等关键指标，反映海上气象条件对风电场经济效应的影响，可为海上风电场的运行维护提供技术参考。     

ASL－12－1型汽轮机发生剧烈振动的原因及处理措施

分析了ＡＳＬ－１２－１型机组停机时发生共振的起因，介绍了剧烈振动带来的损失情况，指出中心孔进油是引起振动的主要原因，提出了为恢复运行、避免事故重现所采取的措施     

600MW机组滑参数停机操作及分析

滑参数停机可以使汽轮机缸体、转子及锅炉本体尤其是各联箱得到均匀而迅速的冷却,缩短机组停机至检修的时间。本文结合天津大唐国际盘山发电有限责任公司600MW机组滑参数停机的操作过程,从机组滑参数停机的准备工作、停机曲线的确定、参数控制方法及限值、机组负荷停留点的选择、减温水的使用、回热系统使用等方面总结了停机过程中的操作、控制等经验,提出了滑参数停机操作过程中的注意事项。     

某燃气轮机保护系统硬回路的 安全完整性等级分析

燃气轮机保护系统最重要的功能就是避免错误停机和拒绝停机，错误停机会带来经济损失，拒绝停 机会引发重大安全事故。保护系统的安全完整性等级是保护系统安全稳定的重要评判指标。以GB/T 20438—2017《电气/电子/可编程电子安全相关系统的功能安全》和GB/T 21109—2007《过程工业领域安全 仪表系统的功能安全》相关标准对某燃气轮机保护系统硬回路的安全完整性等级进行了分析，定量获得保护 系统硬回路安全完整性等级参数，为设计安全可靠的保护系统提供理论依据。     

ASL—12—1型汽轮机发生剧烈振动的原因及处理措施

分析了ＡＳＬ－１２－１型机组停机时发生共振的原因，介绍了剧烈振动带来的原因损失情况，指出中心孔进油是引起振动的主要原因，提出了为恢复运行、避免事故重量同所采取的措施。     

跨季节蓄冷技术及在设施农业应用的经济性分析

为明确跨季节蓄冷技术在设施农业应用场景下的技术经济性,选取济南地区某日光温室群为研究对象,采用以冰源热泵为核心的跨季节蓄冷系统实现温室群的全年冷热管理,建立系统的蓄冷量损失模型和节能、经济、环境效益评价模型,对系统蓄冷量、一次能源利用率、费用年值、动态投资回收期及污染物减排量进行分析,并同其他热泵系统和锅炉系统进行比较.结果表明:跨季节蓄冷体的全年冷量损失在5％以内,最大蓄冷量为170409.07 GJ,至全年结束仍有14509.47 GJ剩余,系统可满足温室群全年供冷供热需求;系统的供冷一次能源利用率为6.27,全年一次能源利用率为1.71,跨季节蓄冷技术的应用大幅提升系统能效,节能效果优越;系统运行费用极低,费用年值最低,动态投资回收期为3.9～6.9年,经济可行性良好;系统较空气源热泵每年可减少13897.90 t CO2、3.61 t SO2、7.16 t NOx和1.41 t烟尘排放,减排率高达77.3％,跨季节蓄冷技术的应用显著减少温室气体及污染物的排放,环境效益显著.     

600MW汽轮机停机快速冷却方法的研究

针对600MW机组采用滑参数停机时，调节级温度下降速度慢的问题，提出了600MW汽轮机配置快玲系统的必要性，分析利用压缩空气进行快冷的安全性。并提出投用快冷系统的操作及注意事项，最后对使用这一方法的效益进行了分析。     

火电厂300MW级机组辅助蒸汽系统拟定与设备选型

该从工程实际出发，重点分析300MW级机组在启动，运行，停机及事故工部的辅助蒸汽用户情况，蒸汽参数及流量分配，并提出系统拟定，设备选型及其优化的基本思想。     

汽机本体及管道保温设计

汽轮机安装完毕后，需进行本体及管道保温。良好的保温可以减少汽轮机启动、运行和停机时上、下缸温差，确保机组安全、可靠地在上述工况下运行，同时可以减少汽轮机本体及其管道表面的散热损失，提高机组的热效率。因上对汽轮机本体部分的保温，从设计到施工都应给予充分的重视。文章运用传热学基本知识，主要阐述了汽轮机保温设计中的平面及管道保温计算方法及计算公式，对保温层结构、材料及施工提出了原则性要求，可供电厂施工单位参考。     

Development and application of organic phase change mixtures in thermal storage gypsum wallboard

A latent heat storage material which would be useful in hot climate is proposed. It is a mixture of 93–95 wt% commercial Methyl Palmitate (MeP) with 7-5 wt% commercial Methyl Stearate (MeS), having a melting-freezing interval of approximately 23–26.5°C and a latent heat of transition of at least 180 kJ/kg.Normal wallboard may be impregnated with up to 25 wt% of one of these mixtures. Air passing over such an impregnated wallboard would be cooled down due to the heat absorption taking place between 23–26.5°C when the mixture melts. Recharging the wallboard will occur at 22–23°C during freezing, when the latent stored heat is released to the cool night air.The total storage capacity of such an impregnated wallboard, in a 3.5°C temperature interval, is at least twelve times higher than the storage capacity of wallboard alone over this range.     

Na_2SO_4·10H_2O复合相变储能体系的热力学测试

制备了一种Na2SO4.10H2O共晶相变蓄冷材料,其相变温度在8℃左右,可作为空调蓄冷材料。本文主要研究了复合相变体系的热化学性质和材料的相变特性。本研究测定出材料的相变潜热为114.37kJ/kg,固体平均比热容为4.68kJ/(kg.K),液体平均比热容为16.18kJ/(kg.K)。材料的主要成分为Na2SO4.10H2O,NaCl,NH4Cl,羧甲基纤维素(CMC)等,其主要特点是原料来源丰富,潜热和显热蓄冷量较大。     

应用溴化锂吸收式制冷技术提高燃气轮机电站发电效率的研究

对燃气轮机进口的空气进行预冷,能够提高发电机组的输出功率。与蓄冷方法相比,使用燃气轮机－蒸汽联合循环电站余热锅炉低压蒸发器的一部分蒸汽为热源,利用溴化锂吸收式制冷机制取冷源,冷却燃气轮机进口处的空气,以提高发电机组的输出功率,该方法技术可行,经济效益显著。     

Simulation of heat transfer in the cool storage unit of a liquid–air energy storage system

An energy storage system that stores energy in the form of liquid air was studied. In this system, the cool storage unit was the most important unit. From the viewpoint of safety and economy, it was most promising to store the cold energy as the sensitive heat of a solid such as pebbles or concrete. A simulator was developed to predict temperature variations of the solid cool storage unit. The simulator calculated unsteady heat transfer between a supercritical gas flow and the solid material. Comparison of calculated and experimental results showed that the temperature variation of the metal cool storage medium was accurate within 11%. The calculated results showed for the concrete cool storage unit that a smaller quantity of medium was required with a smaller pitch of the tube. The minimum quantity of concrete calculated at the smallest pitch was three times that of concrete, which was simply estimated from the heat capacity of concrete and air. The volume required for concrete cool storage was less than 1/100 that of reservoirs for a pumped‐hydro power station having a vertical drop of 500 m. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(4): 284–296, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10035     

Mathematical modelling and experimental investigation of the hybrid desiccant cooling system

In this paper, an experimental study has been conducted on the hybrid desiccant cooling system by removing the latent heat and sensible heat of air separately by mixing it with the desiccant solution in a counter flow manner. This makes air totally dry and thus saves the energy to cool the air in the refrigeration system. The desiccant chosen here is the aqueous solution of calcium chloride. The packed bed inside the absorber as well as the regenerator consists of a polypropylene cascade ring for the efficient mixing of air and desiccant solution. The effects of various parameters such as desiccant inlet temperature, air inlet temperature, mass flow rate of air and desiccant solution have been studied to investigate the performance of the system. Comparing the results with previous studies, a fair agreement has been reported.     

Experimental and thermal analysis of energy efficient novel design wet cooling towers

Waste heat is generally dissipated from process water to atmospheric air in cooling towers. In the present study, a novel design is used to extract more amount of heat without any additional energy input by incorporating secondary ambient air in an induced draft wet cooling tower. In addition, more fresh air is induced in the tower from the rain zone, which increases the effectiveness at any value of the water to air flow rate (L/G ratio). Moreover, tower characteristics, range, and evaporation loss were also increased due to the novel design. It is noteworthy that secondary fresh air increases effectiveness, heat rejection, and tower characteristics by 10.12%, 19.65%, and 26.11%, respectively, and decreases approach by 16.32% at 0.55 L/G ratio, 44°C inlet water temperature, 29.7°C dry bulb temperature, and 18.4°C inlet air wet bulb temperature.     

低温工况热源塔热泵系统应用试验分析

针对热源塔换热能力及热源塔联立热泵主机制热情况分别进行试验研究,并与风冷热泵的制热变化性能进行比较分析。结果表明,控制热源塔进口气液温差恒定的情况下,塔从空气中吸收的热量随环境温度的降低而增加,溶液中溶质的挥发对热源塔吸热量有重要影响;热源塔进口气液温差随环境自然变化的情况下,环境温度与蒸发温度的温差随环境温度的降低而减小,热源塔从空气中吸收的热量也随之减少。在低温工况下,虽然空气含湿量较少,但热源塔热泵系统相比于其他空气作为热源的热泵系统,在潜热换热方面有较大优势。     

An open reversed Brayton cycle with regeneration using moist air for deep freeze cooled by circulating water

This paper presents an open reversed Brayton cycle with regeneration using moist air for deep freeze cooled by circulating water, and proves its feasibility through performance simulation. Pinch technology is used to analyze the cooling of the wet air after compressor and the water used for cooling wet air after compressor. Its refrigeration depends mainly on the sensible heat of air and the latent heat of water vapor, its performance is more efficient than a conventional air-cycle, and the utilization of turbo-machinery makes it possible. The adoption of this cycle will make deep freeze easily and reduce initial cost because very low temperature, about ?55 °C, air is obtained. The sensitivity analysis of coefficient of performance to the efficiency of compressor and the efficiency of compressor, and the results of the cycle are also given. The simulation results show that the COP of this system depends on the temperature before turbine, the efficiency of compressor and the efficiency of compressor, and varies with the wet bulb temperature of the outdoor air. Humid air is a perfect working fluid for deep freeze with no cost to the user.     

辛酸/月桂酸作为相变蓄冷材料的热性能研究

利用差示扫描量热法和低温显微技术研究辛酸、月桂酸及其二元系统的热性能,建立辛酸/月桂酸二元系统相图。实验结果表明:辛酸/月桂酸二元系统的相图较复杂,辛酸质量分数较低时发生转熔,转熔温度约为14℃,转熔点相应的辛酸质量分数为60%;辛酸质量分数较高时发生共晶,共晶熔融温度为7.44℃,相变潜热为136.43J/g,共晶点相应的辛酸质量分数为80%,该共晶熔融温度适合于空调蓄冷。辛酸/月桂酸共晶混合物经过60次、120次冻熔循环后,其共晶熔融温度、熔融热、比热未发生明显变化,具有较好的热稳定性,可用作相变蓄冷材料。     

土壤蓄冷与释冷过程的能量分析

在对土壤蓄冷系统冷量损失过程分析的基础上,提出了地下埋管换热器垫层冷量损失与温差传热冷量损失的概念,并建立了垫层冷量损失和温差传热冷量损失的计算模型;为衡量系统在运行期间地下埋管换热器管束系统的运行效率,建立了埋管换热器管束系统的平均释冷率模型。通过理论研究与模拟计算,分析了土壤初始温度、埋管间距及管束结构对土壤蓄冷系统冷量损失的影响,指出了土壤蓄冷系统冷量损失随土壤初始温度及埋管间距之间的变化规律,为土壤蓄冷系统地下埋管换热器的优化设计提供理论依据。