水电站机组-厂房结构突增负荷过渡过程振动特性研究  

Vibration characteristics of the unit-plant structure of a hydropower station under transient load-up process

作　　者：吴嵌嵌 张雷克[2,3] 马震岳 王雪妮 WU Qianqian;ZHANG Leike;MA Zhenyue;WANG Xueni(Civil Engineering Institute,Sanjiang University,Nanjing 210012,China;College of Water Resources Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China;State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116023,China;School of Hydraulic Engineering,Faculty of Infrastructure Engineering,Dalian University of Technology,Dalian 116023,China)

机构地区：[1]三江学院土木工程学院,南京210012 [2]太原理工大学水利科学与工程学院,太原030024 [3]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116023 [4]大连理工大学建设工程学部水利工程学院,辽宁大连116023

出　　处：《振动与冲击》2019年第18期53-61,共9页Journal of Vibration and Shock

基　　金：国家自然科学基金(51709196);国家重点研发计划项目(2016YFC0401905);海岸和近海工程国家重点实验室开放基金(LP1722)

摘　　要：水电站机组及厂房结构受水、机、电激励影响在过渡工况下振动问题突出,但现阶段相关理论研究严重滞后于工程实际,制约了该结构进一步寻求改善其瞬态振动的合理控制方式及技术措施。为此,以核心水力振源之一——尾水管压力脉动的构建为切入点,从理论分析的角度提出了一种在不同负荷工况下由尾水管偏心涡带诱发的水力激励数学表述,基于已有水力发电系统水-机-电-结构耦联模型,将系统突增负荷过渡过程纳入机组-厂房结构振动研究体系,并对结构在该非稳态运行情况下的振动特性进行了分析。计算结果表明,同稳态工况相比,机组各导轴承结构在瞬态工况下存在运行稳定性降低、振幅明显增大等现象。同时,相对于机组轴系,水电站厂房发电机层楼板在该过渡工况下的振动现象更为显著,特别是竖向振动情况异常突出,位移增幅可达其在稳态运行条件下的数倍。该研究成果可为水电站机组-厂房结构在该过渡工况下的动力响应分析提供合理可靠的模型与研究方法。Influenced by hydraulic,mechanical and electrical excitations during transient process,the vibration of a hydraulic generating set and its plant structure may become extremely extrusive,however,currently the related theoretical investigation obviously falls behind the practical engineering,which restricts the way in pursuit of reasonable control method and technology to further improve the non-stable oscillation problem for the structure.Taking the construction of one of the core hydraulic vibration sources,that is,the pressure fluctuation of draft tube,as the entry point,a mathematical expression for the hydraulic excitation induced by the eccentric vortex of draft tube under different load conditions was proposed in the theoretical analysis.Based on an existing hydraulic-mechanical-electrical-structural model for hydroelectric generation systems,the sudden load-up was integrated into the unit-plant vibration,system and the corresponding dynamic properties was investigated.It is shown from the results that,as compared with the case of stable running,the stability of all guide bearings decreases and the matching vibration amplitude notably increases when the system is operated in transient process.Meanwhile,in contrast with the unit shaft system,the oscillation of the generator floor is more dramatic,especially the vertical vibration appears abnormally prominent with a displacement amplification by several times of that under stable operation.The results can provide a reasonable and reliable model and method to the dynamic response analysis of the hydropower unit-plant structure under sudden load transition condition.

关 键 词：水电站 机组-厂房结构 尾水管压力脉动 突增负荷 瞬态振动 

分 类 号：TH212[机械工程—机械制造及自动化] TH213.3