无旁通烟囱燃气_蒸汽联合循环机组的运行维护和停运

论述了无旁通烟囱燃气－蒸汽联合循环机组运行维护和停运的特点,探讨了它与火力发电厂和有旁通烟囱联合循环的不同之处,总结了机组运行维护和停动的经验,可供运行人员和设计人员参考。     

无旁通烟囱燃气--蒸汽联合循环机组的启动

１引言通常燃气———蒸汽联合循环都设有旁通烟囱,可使机组运行灵活方便,对余热锅炉起到保护作用,然而为了减少设备的初始投资,现在有的联合循环不设置旁通烟囱见图１。这类机组的启动运行不同于有旁通烟囱的联合循环,有其自身的特点。２无旁通烟囱联合循环机组启动...     

燃气-蒸汽联合循环不设置旁通烟囱的分析

分析无旁通烟囱燃气—蒸汽联合循环的特点，指出燃机启动会对余热锅炉产生热冲击，提出根据机组的实际运行情况来确定是否设置旁通烟囱，可供联合循环方案设计者及运行人员参考。     

标准联合循环装置的价格

标准联合循环装置的价格“ＧａｓＴｕｒｂｉｎｅＷｏｒｌｄ１９９６Ｈａｎｄｂｏｏｋ”报导了标准联合循环装置的价格。该价格是指基本的烧天然气的联合循环动力装置平均的标准预算价格，以１９９６年美元计算，包括下列设备的购置费用：燃气轮发电机组，没有旁通烟囱不补...     

YD5.78烟气挡板门的设计与探讨

YD系列烟气挡板门是燃气轮机余热锅炉必不可少的部件，它在整个烟气系统里起了三通转换阀的作用：关闭锅炉侧进口，燃机排气直接进入旁路烟囱，排入大气，系统单循环发电；关闭旁通侧进口，燃机排气进入余热锅炉，实现余热再利用，系统联合循环发电。     

标准小型联合循环装置的价格

“Gas Turbine World”1996年5~6月号报道了标准小型联合循环装置的价格,该价格是指平均的烧天然气的联合循环基本装置的价格,以1996年美元计算,包括下列没备的购置费用:燃气轮发电机组,无旁通烟囱不补燃的多压余热锅炉,凝汽式多压汽轮发电机组,升压变压器、水冷式排热系统,标准的控制装置,起动系统和装置的辅机,并且通常装有干低NO_x燃气轮机。     

燃气-蒸汽联合循环无旁通烟囱余热锅炉煮炉方案的选择

论述了无旁通烟囱余热锅炉的启动特点；介绍了过热器应力腐蚀现象，指出对无旁通烟囱余热锅炉不可采用常规的方式煮炉，给出了两种切实可行的煮炉方案。     

燃气—蒸汽联合循环无旁通烟囱余热锅炉煮炉方案的选择

论述了无旁通烟囱余热锅炉的起动特点，介绍了过热器应力腐蚀现象，指出了对于无旁通烟囱余热锅炉不可采用常规的方式煮炉，给出了两种切实可行的煮炉方案。     

非均匀辐照下光伏组件旁通二极管可靠性研究

通过调研光伏组件室外运行与室内测试条件下光伏旁通二极管实际失效数据,分析光伏旁通二极管失效概率与工作温度、运行时间等的关系。通过环境箱和双极电源结合,设置高温加正向偏置、高低温循环加正向偏置、高低温循环加反向偏置、正反向偏置循环的室内测试条件,模拟典型光伏组件表面非均匀辐照分布情况下旁路二极管的工作情况并进行耐久性实验。实验结果表明:较高环境温度时,因固定遮挡引起的旁通二极管长期正向偏置情况下,光伏组件存在失效风险。     

国外燃气—蒸汽联合循环汽轮机

结合介绍国外燃气－蒸汽联合循环汽轮机的实绩和发展,综合联合循环汽轮机在蒸汽参数、总体布置、快速启动和两班制运行、结构设计等方面的特点以及典型的应用实例,对联合循环汽轮机的总体及其特色有效全面的分析。     

Life cycle assessment of an alkaline fuel cell CHP system

A life cycle assessment (LCA) of an alkaline fuel cell based domestic combined heat and power (CHP) system is presented. Literature on non-noble, monopolar cell design and stack construction was reviewed, and used to produce a life cycle inventory for the construction of a 1 kW stack. Inventories for the ancillary components of other commercial fuel cell products were consulted, and combined with information on the fuel processing requirements of alkaline cells to suggest a hypothetical balance of plant that would be required to produce AC electricity and domestic grade heat from natural gas and air.     

Cost numerical optimization of the triple‐pressure steam‐reheat gas‐reheat gas‐recuperated combined power cycle that uses steam for cooling the first GT

Optimization is an important method for improving the efficiency and power of the combined cycle. In this paper, the triple‐pressure steam‐reheat gas‐reheat gas‐recuperated combined cycle that uses steam for cooling the first gas turbine (the regular steam‐cooled cycle) was optimized relative to its operating parameters. The optimized cycle generates more power and consumes more fuel than the regular steam‐cooled cycle. An objective function of the net additional revenue (the saving of the optimization process) was defined in terms of the revenue of the additional generated power and the costs of replacing the heat recovery steam generator (HRSG) and the costs of the additional operation and maintenance, installation, and fuel. Constraints were set on many operating parameters such as air compression ratio, the minimum temperature difference for pinch points (δT_ppm), the dryness fraction at steam turbine outlet, and stack temperature. The net additional revenue and cycle efficiency were optimized at 11 different maximum values of turbine inlet temperature (TIT) using two different methods: the direct search and the variable metric. The optima were found at the boundaries of many constraints such as the maximum values of air compression ratio, turbine outlet temperature (TOT), and the minimum value of stack temperature. The performance of the optimized cycles was compared with that for the regular steam‐cooled cycle. The results indicate that the optimized cycles are 1.7–1.8 percentage points higher in efficiency and 4.4–7.1% higher in total specific work than the regular steam‐cooled cycle when all cycles are compared at the same values of TIT and δT_ppm. Optimizing the net additional revenue could result in an annual saving of 21 million U.S. dollars for a 439 MW power plant. Increasing the maximum TOT to 1000°C and replacing the stainless steel recuperator heat exchanger of the optimized cycle with a super‐alloys‐recuperated heat exchanger could result in an additional efficiency increase of 1.1 percentage point and a specific work increase of 4.8–7.1%. The optimized cycles were about 3.3 percentage points higher in efficiency than the most efficient commercially available H‐system combined cycle when compared at the same value of TIT. Copyright © 2008 John Wiley & Sons, Ltd.     

High performance nickel–metal hydride battery in bipolar stack design

The consumption of fuel in cars can be reduced by using hybrid concepts. Even for fuel cell vehicles, a high power battery may cut costs and allow the recovery of energy during retarding. Alkaline batteries, such as nickel–metal hydride batteries, have displayed long cycle life combined with high power ability. In order to improve the power/energy ratio of Ni/MH to even higher values, the cells may be arranged in a bipolar stack design.     

联合循环机组的数学模型及其参数辨识研究

联合循环电站由于其复杂的控制系统和强耦合的非线性关系,其数学模型非常复杂,开展联合循环机组的建模和参数测试研究具有重要的学术意义和工程应用价值。本文提出了适用于电网一次调频和稳定性分析的联合循环电站模型,采用改进最小二乘参数辨识方法对某400MW联合循环机组的模型参数进行了辨识,采用辨识的参数进行了仿真分析并与机组运行的实测数据进行了对比,两者能够很好地吻合,证明了所提出模型和辨识方法的有效性,为联合循环电站的一次调频和动态特性分析奠定了基础。     

Numerical based design of exhaust gas system in a cogeneration power plant

Among the various aspects that have to be analysed in a cogeneration and combined cycle plant design, the exhaust gas stack design can represent a critical aspect, in particular when a by-pass stack, which allows the modulation of heat-to-power generation, is present, since it may influence the entire system working condition. To properly take into account the large number of the different requirements which enter in an exhaust gas system design, a multidisciplinary analysis involving numerical integrated approaches can be adopted in order to obtain an optimally designed stack system. In this paper, the design of the exhaust gas system in a cogeneration plant is analysed. The design is performed numerically through a three-dimensional integrated numerical code. Different design solutions are simulated and the results discussed in detail.     

Parametric analysis of a coal based combined cycle power plant

In the present paper thermodynamic analyses, i.e. both energy and exergy analyses have been conducted for a coal based combined cycle power plant, which consists of pressurized circulating fluidized bed (PCFB) partial gasification unit and an atmospheric circulating fluidized bed (ACFB) char combustion unit. Dual pressure steam cycle is considered for the bottoming cycle to reduce irreversibilities during heat transfer from gas to water/steam. The effect of operating variables such as pressure ratio, gas turbine inlet temperature on the performance of combined cycle power plant has been investigated. The pressure ratio and maximum temperature (gas turbine inlet temperature) are identified as the dominant parameters having impact on the combined cycle plant performance. The work output of the topping cycle is found to increase with pressure ratio, while for the bottoming cycle it decreases. However, for the same gas turbine inlet temperature the overall work output of the combined cycle plant increases up to a certain pressure ratio, and thereafter not much increase is observed. The entropy generation, the irreversibilities in each component of the combined cycle and the exergy destruction/losses are also estimated. Copyright © 2005 John Wiley & Sons, Ltd.     

Development and thermodynamic assessment of a novel solar and biomass energy based integrated plant for liquid hydrogen production

In this paper, a combined power plant based on the dish collector and biomass gasifier has been designed to produce liquefied hydrogen and beneficial outputs. The proposed solar and biomass energy based combined power system consists of seven different subplants, such as solar power process, biomass gasification plant, gas turbine cycle, hydrogen generation and liquefaction system, Kalina cycle, organic Rankine cycle, and single-effect absorption plant with ejector. The main useful outputs from the combined plant include power, liquid hydrogen, heating-cooling, and hot water. To evaluate the efficiency of integrated solar energy plant, energetic and exergetic effectiveness of both the whole plant and the sub-plants are performed. For this solar and biomass gasification based combined plant, the generation rates for useful outputs covering the total electricity, cooling, heating and hydrogen, and hot water are obtained as nearly 3.9 MW, 6584 kW, 4206 kW, and 0.087 kg/s in the base design situations. The energy and exergy performances of the whole system are calculated as 51.93% and 47.14%. Also, the functional exergy of the whole system is calculated as 9.18% for the base working parameters. In addition to calculating thermodynamic efficiencies, a parametric plant is conducted to examine the impacts of reference temperature, solar radiation intensity, gasifier temperature, combustion temperature, compression ratio of Brayton cycle, inlet temperature of separator 2, organic Rankine cycle turbine and pump input temperature, and gas turbine input temperature on the combined plant performance.     

Thermoeconomic evaluation of the feasibility of highly efficient combined cycle power plants

The paper proposes an analysis of the feasibility of highly efficient combined plants. The aim of the paper is to discuss and analyze different strategies for the increase of the efficiency of the combined cycle power plants with respect to those usually proposed in the literature. Resorting to the optimization of the components, joined with the use of regeneration and postcombustion (reheat) in the topping cycle it is shown how the combined plant efficiency can rise well over the actually well known limit of 60%. The possibility of obtaining such a high efficiency value is confirmed also by the proposed thermoeconomic optimization, based on the minimization of the total cost of the plant per unit power, obtained referring to a common economic basis the cost of the exergy losses and the costs of the components. The feasibility of obtaining combined plant with efficiency higher than 62%, simply by best fitting the available technology and without waiting for meaningful technological improvement of the gas turbines, is demonstrated.     

高气价下联合循环机组建设类型探讨

本文对具有代表性发电工程造价和电价进行对比分析,燃气机组燃料费相比燃煤机组和核电机组占电价的比例处于较高水平,燃料价格变化对电价的影响较大.在高气价且价格又不稳定的情况下,新建哪种类型的联合循环机组才有竞争力,文中对几种类型的燃气联合循环机组进行探讨,并对天然气发电政策提出几点建议.