差动保护在拉西瓦电站发电组保护中的应用

根据国内外运行经验统计,大型机组的故障率尤其是电气故障率远远高于小型机组。大型发电机造价高昂,结构复杂,一旦发生故障遭到破坏,其检修难度大,检修时间长,将造成很大的经济损失。由于单机容量大,发电机保护的误动和拒动都将造成十分严重的后果,所以对大型机组继电保护主保护的配置、原理和技术提出了更高的要求。文章以拉西瓦水电站为例,详细介绍了发变组差动保护的配置方案及特点。     

600MW空冷供热汽轮机可行性和可靠性分析

结合目前国内提出的几个600 MW超临界空冷供热机组项目,通过大量的调研工作,以300 MW,600 MW湿冷供热机组到300 MW,600 MW空冷供热机组机型转换的技术路线为主线进行分析,论证600 MW超临界空冷供热汽轮机的可行性和可靠性.     

大别山电厂2×640MW机组工程建设经验

黄冈大别山发电有限责任公司2×640MW超临界机组工程在建设过程中对进度管理、工期控制和工程质量控制采取了一系列措施,特别在设备监造、推行样板工程、对标管理上,提出了相应的措施,对汽轮机弹簧基础的施工（国内首次用于600MW以上机组）采取重点管理,保证了工程质量。     

黄岛电厂660MW机组励磁转轴异常振动的诊断及处理

黄岛电厂660MW机组大修后启动升速至3000r/min时,励磁转轴9号轴振迅速爬升至251μm,振动特征与碰磨振动很相似,但通过对励磁转轴进行高速动平衡,降低了定速振动值及爬升速度,振动水平达优良,介绍了该异常振动现象特征、原因及处理过程。     

国产引进型600MW汽轮机调试若干问题分析及对策

针对近几年湖南省投产的国产引进型600MW汽轮机在调试中发生的主要问题进行分析,介绍了采取的对策,供同类型机组设计、安装、调试和运行借鉴。     

Harmonic balance Navier‐Stokes aerodynamic analysis of horizontal axis wind turbines in yawed wind

Multimegawatt horizontal axis wind turbines often operate in yawed wind transients, in which the resulting periodic loads acting on blades, drive‐train, tower, and foundation adversely impact on fatigue life. Accurately predicting yawed wind turbine aerodynamics and resulting structural loads can be challenging and would require the use of computationally expensive high‐fidelity unsteady Navier‐Stokes computational fluid dynamics. The high computational cost of this approach can be significantly reduced by using a frequency‐domain framework. The paper summarizes the main features of the COSA harmonic balance Navier‐Stokes solver for the analysis of open rotor periodic flows, presents initial validation results on the basis of the analysis of the NREL Phase VI experiment, and it also provides a sample application to the analysis of a multimegawatt turbine in yawed wind. The reported analyses indicate that the harmonic balance solver determines the considered periodic flows from 30 to 50 times faster than the conventional time‐domain approach with negligible accuracy penalty to the latter.     

Experimental identification of modal parameters of an industrial 2‐MW wind turbine

This contribution presents modal testing of a 2‐MW wind turbine on a 100‐m tubular tower with a 93‐m rotor developed by W2E Wind to Energy GmbH. This research is part of the DYNAWIND project of the University of Rostock and W2E. Beside classical modal analysis schemes, this contribution mainly focusses on the application of operational modal analysis techniques to a wind turbine. Specific problems are addressed, and hints for modal testing on wind turbines are given. Furthermore, an effective measurement setup is proposed for identification of the modal parameters of a wind turbine. The measurement campaign is divided in two parts. First, a measurement campaign using 8 sensor positions on a rotor blade was done while the rotor is lying on ground. Second, a detailed measurement campaign was done on the entire wind turbine with the rotor locked in Y position using 61 sensor positions on the tower, the mainframe, the gearbox, the generator, and the low‐voltage unit. While the rotor blade was tested by classical and operational modal analysis techniques, the entire wind turbine was tested by operational modal analysis techniques only. The mode shapes and eigenfrequencies of the wind turbine identified within the measurement campaigns are within the expected range of the design values of the wind turbine. But in contrast, the damping ratios differ strongly from those given in guidelines and literature. Furthermore, a strong influence of aerodynamic damping compared to structural damping is observed for the first tower mode even for a parked wind turbine.     

1 000 MW超超临界二次再热燃煤发电技术

为节约一次能源、加强环境保护、减少温室气体排放和提高机组的经济性,自主研发、自主设计、自主制造和自主建设了国电泰州电厂二期1 000 MW超超临界二次再热燃煤发电示范工程,介绍了机组总体技术方案,包括机组主机参数选择、锅炉与汽轮机研发,系统优化与节能减排集成,自动控制系统研究。机组投产后发电效率分别高达47.81%、47.95%,机组供电煤耗分别达到266.57 g/（kW·h）、265.75 g/（kW·h）,烟尘、SO₂、NO_x排放浓度在标准状态下分别低于5 mg/m³、35 mg/m³、50 mg/m³,达到并优于超低排放要求。示范工程的成功投产和稳定运行为中国开发更高参数、更高效率、更为清洁的燃煤发电技术奠定了基础,为建设同类机组积累了宝贵的经验,大幅提高了中国燃煤发电技术的国际竞争力。     

Latest Developments of HgCdTe e-APDs at CEA LETI-Minatec

In this communication, we report on the electro-optical characterization of planar back-side-illuminated HgCdTe electron initiated avalanche photodiode (e-APD) test arrays with cut-off wavelengths λ _c = 2.4 μm, λ _c = 4.8 μm, and λ _c = 9.2 μm. The e-APDs were manufactured at LETI using absorption layers grown by molecular beam epitaxy (MBE). We present measurements of the distributions in gain, noise, and equivalent input dark current. The mid-wave (MW) diodes yielded a very low dispersion (2%) and high operability (98%) for gains up to M = 200. The excess noise factor and equivalent input current (I _{eq_in}) operability were slightly lower, due to defects in the depletion region. The lowest measured value of I _{eq_in} = 1 fA corresponds to the lowest level measured so far in HgCdTe e-APDs and opens the way to new applications. The gain in the long-wave (LW) diodes was limited by tunnelling currents to a value of M = 2.4, associated with an average noise factor F = 1.2. A gain of M = 20 at a bias of −22.5 V was demonstrated in the short-wave (SW) e-APDs.     

工业锅炉CAD在新型锅炉设计中的应用

新型29 MW锅炉利用工业锅炉CAD系统进行了设计,充分发挥了计算机技术的优越性,为实现锅炉技术与计算机技术的结合发挥了积极的作用。实践证明,工业锅炉CAD软件能提高设计效率,能对锅炉方案进行优选对比以更好地体现所设计锅炉的特色,并能使计算与绘图有机地融为一体,为锅炉设计实现技术上的创新提供有利条件。