二十万千瓦汽轮机盘车装置的自动化问题

我厂二十万机盘车装置采用摆轮径向啮合机构、手动操作、高速盘车、盘车转速为40转/分。这种机构的盘车装置也在我厂~#06机(五万)和~#43(十万)上采用,(图1)。按我厂编制的盘车装置使用说明书中规定,该盘车装置必须在汽轮机转子处于静止状态,亦即大齿轮的转速为零的情况下方可投入。投入啮合时,如摆轮与大齿轮不能处于正常啮合位置时,则需要手动操作,盘转电动机轴端上的小手轮,使摆轮调整到啮合位置后方可启动电动机实现盘车。这种运行方式不能满足汽轮机程序控制的自动化要求。自动盘车机构,在国外机组,如陡河电站的日立250MW机和元宝山电站的300MW     

汽轮机盘车装置的设计

东汽电液操纵齿轮切向啮入式自动盘车装置广泛用于50MW、135MW、200MW、300MW等汽轮机组上。经过不断改进，具有静态自动投入、零转速启动、降压启动、就地及远方操作等功能。文章较详细地介绍了该盘车装置的结构及工作原理，并分析了关键机构的设计思想，无论是对新工程开发设计还是盘车装置的安装及检修都具有一定的启发和参考价值。     

MPCP1（M701F）联合循环机组盘车自动投入故障的处理

本文叙述了MPCP1（M701F）联合循环机组盘车自动投入发生异常情况的现象,剖析了盘车装置的设计原理,分析了故障的原因,并最终通过相应的调整解决了这一问题。     

9E汽轮机盘车装置变频改造

对9E汽轮机盘车系统的传动方式进行了介绍,通过对盘车装置投入时脱扣原因的深入分析,提出采用变频方式启动盘车电机,以仅数千元的改造成本,恢复盘车自动投入功能,使长期以来困扰运行人员的盘车投入脱扣问题得以解决。     

某核电汽轮机盘车无法投运原因分析及处理

文章分析了某核电1、2号机组盘车小齿轮无法脱开故障的原因.介绍了通过封堵盘车排油孔、提高盘车润滑油压、抬高动力油电磁阀的位置,以消除盘车小齿轮无法脱开到位故障的方法.介绍了通过调整大轴顶起高度及控制轴瓦平行度以保证盘车顺利投运的方法.实践证明这些措施能够较好地将盘车无法投运故障消除,使盘车及时投运,确保机组启、停安全.     

盘车齿轮与转子齿轮摩擦问题分析与处理

某电厂汽轮机盘车装置改造投运时,发生盘车齿轮与转子大齿轮发生碰磨现象,且盘车投运后盘车箱体温度高达130℃,通过对该类型盘车的结构、原理以及现场解体检查的实际情况出发,对碰磨故障和盘车箱体温度高原因进行了分析,通过对盘车启动方式和油系统进行改造,该问题得到了圆满处理。     

超临界620MW汽轮机盘车装置脱扣原因分析与处理

某新建火电厂两台超临界620MW汽轮机在调试期间均出现了盘车脱扣、转子自转问题,通过逐一排查,发现导致盘车脱扣的原因为高压顶轴油使转子自转,且自转转速高于盘车转速。对顶轴油母管油压和顶起高度重新调整后,两台机组在接下来的整套启动期间均未发生盘车脱扣的问题,为今后同类型机组盘车装置和顶轴油系统调试时提供参考。     

汽动锅炉给水泵组盘车装置探讨

由于锅炉给水泵卡泵，盘车装置盘不动，而且盘车装置不能满足锅炉给水泵高速盘车的要求，国内不少电厂索性将盘车装置废弃不用了。卡泵问题与高速盘车问题是不是不能解决？汽动给水泵组是不是可以取消盘车装置？国内目前有没有一个完善解决汽动给水泵组盘装置的实例？本文将对以上问题进行探讨。     

一起盘车事故的分析与处理

在机组停运的过程中,因盘车装置无法投入,而且盘车装置短期无法修复,手动盘车无效的情况下,为使机组安全停运,有效地防止汽轮机大轴弯曲事故的发生,制定了详细的行车盘车及后备方案,确保了机组安全.通过对故障原因的进一步排查,找到了盘车卡死的根本原因,消除了事故隐患.     

给水泵汽轮机的高速变频盘车装置

介绍了新型高速变频盘车装置的特点,以及盘车装置在实际运用中所遇到的问题和改进方式.并对其应用前景作了详细阐述.该装置既满足了给水泵高转速盘车,避免卡涩的要求,又可在低速下实现盘车的自动啮合,成功解决汽动给水泵组的盘车转速问题.该装置同样可在现有汽动给水泵组中推广应用,提高机组运行的可靠性.     

椭圆封头旋压控制参数确定的研究

椭圆封头仿形旋压法的技术难点是工艺控制参数的确定。文中分析了椭圆封头仿形旋压成形机理,建立了旋压轨迹方程,较系统地提出了控制封头旋压的渐开线仿形模板参数及旋压道次间距序列的确定方法,并成功地进行了工艺试验,为回转体的仿形（或数控）旋压控制参数的确定提供参考。     

含旋转备用的独立风光储系统控制与仿真

鉴于独立风光储系统配备一定容量的旋转备用的必要性,利用小型柴油发电机作为独立风光储系统的旋转备用,在PSCAD平台上建立了独立风光储系统的仿真模型,并提出将风力发电和光伏发电系统均采用恒功率(PQ)控制、蓄电池和超级电容器的混合储能系统作为主控制器采用恒压恒频(V/f)控制的控制策略,EMTDC仿真结果验证了将旋转备用控制引入独立风光储系统的正确性和有效性。     

求解计及可靠性机组启停的随机摄动蚁群算法

利用安全函数的概率性分析方法并针对机组启停问题对系统的旋转备用需求进行评估。针对该评估模型，在基本蚁群优化算法的基础上，提出了一种新的随机摄动蚁群优化算法来进行求解。对模型的转化、可靠性约束及其他运行约束的处理等进行了较深入的研究。试验系统的计算结果表明：一方面该算法可以有效地克服基本蚁群算法容易出现停滞现象的缺陷，具有更好的全局优化能力；另一方面所做的期望安全水平对优化解的影响的敏感度分析，对实际工程决策具有一定的指导意义。     

A Comprehensive,One-Dimensional Model of Fiber Processing

Abstract

A one-dimensional model of fiber processing is formulated based on first principles. Several special cases are then considered, including an acetone, acetate, water, and air dry spinning process. Selected dry spinning numerical predictions are presented graphically and used to illustrate interesting aspects of the modeling.     

Optimal generation and reserve dispatch in a multi-area competitive market using a hybrid direct search method

With restructuring of the power industry, competitive bidding for energy and ancillary services are increasingly recognized as an important part of electricity markets. It is desirable to optimize not only the generator’s bid prices for energy and for providing minimized ancillary services but also the transmission congestion costs. In this paper, a hybrid approach of combining sequential dispatch with a direct search method is developed to deal with the multi-product and multi-area electricity market dispatch problem. The hybrid direct search method (HDSM) incorporates sequential dispatch into the direct search method to facilitate economic sharing of generation and reserve across areas and to minimize the total market cost in a multi-area competitive electricity market. The effects of tie line congestion and area spinning reserve requirement are also consistently reflected in the marginal price in each area. Numerical experiments are included to understand the various constraints in the market cost analysis and to provide valuable information for market participants in a pool oriented electricity market.     

Effect of optimal spinning reserve requirement on system pollution emission considering reserve supplying demand response in the electricity market

Pollution emission reduction is becoming an inevitable global goal. Incorporating pollution reduction goals into power system operation affects several different aspects, such as unit scheduling and system reliability. At the same time, changes in the energy scheduling change the required optimal reserve amount. Optimal spinning reserve scheduling also affects the energy market scheduling. Optimal reserve allocation changes the energy scheduling, which affect the amount of pollution emission. Therefore, incorporating pollution emission reduction and optimal spinning reserve scheduling cannot be studied separately. Analysis of the system effects of pollution reduction should be performed considering the ancillary service market, specificity the optimal spinning reserve scheduling. This problem is addressed in this paper by incorporating optimal spinning reserve scheduling in a combined environment economic dispatch (CEED) in one objective function. The framework of this paper enables the study of the effect of optimal reserve scheduling and emission reduction as well as an analysis of the system effects of pollution reduction. With the increased AMI and smart grid realization, the reserve supplying demand response (RSDR) is becoming an important player in the reserve market, and thus, these resources are also taken into account. In this paper, the objective function is social cost minimization, including the costs associated with energy provision, reserve procurement, expected interruptions and environmental pollution. A MIP-based optimization method is developed, which reduces the computational burden considerably while maintaining the ability to reach to the optimal solution. The IEEE RTS 1996 is used as a test case for numerical simulations, and the results are presented. The numerical results show that optimal reserve scheduling and RSDR utilization resources have a considerable impact on environmental–economic cost characteristics.     

含沙水流中金属材料磨蚀机理分析

木文介绍了在不同含沙量、不同流速中，不锈钢、碳钢、堆焊焊条及合金粉末喷焊材料的磨蚀特性。分析了材料抗磨蚀特性与含砂量、流速的关系；并对磨蚀部位进行电镜扫描，从微观上探讨了磨蚀机理。     

Air-cooling induced from spinning of spin-casting moulds

The quality of spin cast products and mould life are critically dependent on the thermal conditions they are exposed to. An investigation was carried out on the effect of air-cooling induced by the spinning of the mould and its consequences on the thermal process. A system was developed to optimise the thermal process during casting, utilising a theoretical analysis of the air-flow characteristics in a cooling tube submerged in a silicon mould and the characteristics of convection heat transfer associated with the mould and cast part. A numerical simulation of the casting process was also used in this process. The effect of the developed system on the thermal process was determined experimentally and it was found that a system of air-cooling, automatically induced from the spinning of the mould, is feasible in optimization of the thermal process.     

Flame dynamics and unsteady heat release rate of self-excited azimuthal modes in an annular combustor

This paper presents an experimental study into the structure and dynamics of the phase-averaged heat release rate during self-excited spinning and standing azimuthal modes in an annular combustion chamber. The flame response was characterised using two methods: high-speed OH^∗ chemiluminescence imaged above the annulus to investigate the structure of the phase-averaged fluctuations in heat release rate, and high-speed OH-PLIF measured across the centreline of two adjacent flames to investigate phase-averaged flame dynamics. Two-microphone measurements were obtained at three circumferential locations to determine the modes and the amplitude of the velocity fluctuations. It was found that the flame responds differently to spinning and standing wave modes. During standing wave modes, the amplitude of the unsteady heat release rate of each flame (sector) varied according to its location in the mode shape with maximum fluctuations occurring at the pressure anti-nodes and minimum fluctuations occurring at the pressure nodes. At the pressure anti-nodes, peak fluctuations result from the production of flame surface area by axisymmetric flame motions caused by the modulation of flow at the burner inlet by the pressure fluctuations. However, at the pressure nodes, an anti-symmetric, transverse flapping motion of the flame occurred producing negligible unsteady heat release rate over the oscillations cycle via the mechanism of cancellation. During spinning modes, the structure of the heat release rate was found to be asymmetric and characterised by the preferential suppression of shear layer disturbances depending on the spin direction.