水电站发电机组常见故障维修

1、水电站发电机组常见故障维修河北工程大学毕业翻译学院专业姓名学号指导教师热动水动方向 _ 2019 年 6 月 3 日水电站发电机组常见故障维修摘要：随着社会的进步 , 经济的高速发展 , 人们生活水平有了很大提高 , 人们的用水 辆逐渐增加。在水电走进越来越多家庭的同时 , 水电站发电机组发生故障就需要有关人员 当场检查、诊断并且排除故障。由于水轮机发电机组的结构比较复杂有机械部分、电气部 分以及油、气、水系统它受系统和用户运行方式的影响还受天气等自然条件影响，容易发 生故障或者不正常运行状态，某一次故障可能是一种偶然情况但对整个机组运行来说又是 一种必然事件，运行人员应从思想、技术、组织等各

2、个方面做好充分准备。本文就水电站 发电机组常见故障以及维修进行探讨。关键词：水电站发电机组常见故障维修一 水电站电气部分常见故障发电机在运行过程中，由于外界的影响和自身的原因，发电机的参数将发生变化，并 可能超出正常运行允许的范围。短时间超过参数规定运行或超过规定运行参数不多虽然不 会产生严重后果，但长期超过参数运行或者大范围超过运行参数就有可能引起严重的后果， 危机及发电机的安全应该引起重视。1、发电机过负荷运行中的发电机，当定子电流超过额定值 1.1 倍时，发电机的过负荷保护将动作发出 报警信号。运行人员应该进行处理，使用其恢复正常运行。若系统未发生故障，则应该首 先减小励磁电流减小发电机

3、发出的无功功率；如果系统电压较低又要保证发电机功率因数 的要求，当减小励磁电流仍然不能使用定子电流降回来额定值时，则只有减小发电机有功 负荷；如果系统发生故障时，允许发电机在短时间内过负荷运行，其允许值按制造厂家的 规定运行。 2、发电机转子一点接地发电机转子接地有一点接地和两点接地，转子接地还可分为瞬时接地、永久接地、断 续接地等。发电机转子一点接地时，因一点接地不形成回路，故障点无电流通过，励磁系统仍能 短时工作，但转子一点接地将改变转子正极对于地电压和负极对于地电压，可能引发转子 两点接地故障；继而引起转子磁拉力不平衡，造成机组振动和引起转子发热。3、转子回路两点接地发电机转子两点接地时

4、，由于形成回路，故障点有电流通过。4、发电机温度过高 V发电机在运行中，如果定子、转子或者铁心温度超过规定值，应该及时检5、发电机定子接地发电机定子接地是指发电机定子绕组回路或与定子绕组回路直接相连的一次系统发生 的单相接地短路。定子接地分为瞬时接地、永久接地、断续接地等。二、水电站机械部分常见故障1 、强烈的振动是水轮机组运行中一种常见的故障，其特征不易捕捉，难以铲除事故 隐患，不仅影响水轮机组的正常运行，而且还会降低机组和零部件的使用寿命。2、水轮机空蚀是水轮机损伤的主要原因，其损伤程度已成为确定是否进行大修的关 键参数，因空蚀将直接降低水轮机机组经济效益和安全性。3、随着水力发电机组在整

5、个电网中的比重越来越大，年平均发电时间延长，检修时 间缩短，一旦因事故停机，造成的经济损失极为严重。此外，电网调度中越来越强调水电 机组的调峰作用，要求充分利用水电厂最大出力。4、近年来高水头、高转速、高效率、大容量的水电机组的设计实践中趋向使用高强 度的材料，构件更加灵活，刚度的减小和机组尺寸的增加，必然会带来更多的稳定性问题。三、水电站发电机组常见故障的诊断方法1 、发电机组故障诊断一看。诊断发电机组 , 首先需要维修人员观察发电机组的外观 , 来确定机型、使用年 限、使用状况和需要维修的位置。发电机上的生产日期上明确地标注了生产日期 , 从而可 以准确判断出使用年限 , 有经验的维修人员

6、甚至在观察发电机的使用状况后 , 便可发现故 障所在。 二听。维修技术人员根据发电机出现的故障向发电站人员了解具体状况 , 例如 发电机产生故障时的表现 , 发电机型号 , 保养状况和使用时的习惯等。在与发电站工作人 员交流时 , 认真记下工作人员所描述的故障和出现故障的部位 , 以便准确作出维修方案 , 在深入交谈时了解保养状况后 , 可以给发电站提出好的建议和意见 , 以便维修好后对发电机的保养。在询问后 , 维修人员基本上确定了故障发生的部位和原因。经验丰富的水电站工作人 员提供的信息基本上准确 , 这样就避免了维修人员对发电机不必要的检查 , 节省了时间和 人力。即使工作人员经验不是很

7、丰富 , 通过交谈也可以基本确定发生故障的状况 , 了解到 一些有用的信息。发电机产生故障的原因有很多 , 具体部位如发电机组供电系统 , 发电机 组机械系统 , 发电机组引水系统及其它电控系统 , 都可能引起发电机组无法工作。在不事 先询问工作人员的情况下就进行维修 , 便会觉得无从下手 , 头绪乱 , 通过工作人员的交谈 了解了发电机组启动困难的现象 , 时好时坏 , 故障发生大多是在发电机组使用一段时间停 用十几分钟后发生 , 通过了解这些故障发生的条件和现象 , 基本上可以排除发点机组机械 系统等原因 , 通过运用与水电站工作人员沟通后 , 迅速快捷地排除故障 , 保证发电机组正 常运

8、行。发电机组产生故障的原因很多都与使用年限有关 , 使用一段时间后许多故障接踵而来 一些表面看起来并不起眼的故障 , 似乎并不影响发电机组的正常工作 , 但是经过维修人员 的检查后会发现这些故障 , 这些隐患不容忽视。2.使用专用仪器诊断发电机组设备仪器设备诊断法是指运用专业的检测设备、工具和仪器来检测发电机组的结构构成、 技术状态 （如间隙, 振动频率 , 声能, 红外线 ） 波形等来诊断发电机组的方法。仪器设备 的改进和发展 , 能准确地对发电机组出现的故障作出正确的诊断 , 并能分析出现故障的原 因, 在线检测快捷准确。利用各种现代的检测技术、测仪器和设备完成特定的测试任务的综合测试系统

9、 , 在发 电机组故障诊断和检测实现现代化方面具有重要作用。如利用虚拟仪器技术开发的发电机 组检测系统、发电机组故障诊断计算机分析系统、发电机组性能检测与故障诊断系统等等。四、水电站发电机组常见故障与维修针对水电站发电机组存在的那些常见故障 , 发电站经营者应该采取有效的措施 , 预防 发电机组常见故障的产生。为了更好的使发电机组进行工作 , 水电站应该对于发电机组的 使用进行提前控制 , 并且建立发电机组使用的信息库 , 将发电机组使用的信息保存完整。在工作人员提出发电机 组使用申请的时候 , 水电站应该审核和调查发电机组使用信息资料库里面的发电机组前一 次使用信息资料 , 对于工作人员的发

10、电机组使用情况进行全面、客观的评估 , 适度的实 施发电机组使用计划 , 将发电机组出现故障的风险降到最低。水电站水轮机设备的检修模式主要依赖于先进技术的应用和完善，特别是象泥沙含量 较高的水电站，应该打破传统的管理方式，给生产运行单位一定设备检修管理权限，改变 传统的集权式检修管理制度，应该加强对水轮机运行工况的监视，根据水轮机的运行情况制定合理的检修模式，既不机械的套用传统的计划检修模式，也不能盲目引进状态检修理 念。随着制造工业的发展，科学技术的进步，设备状态检修的前景是无限美好的。Common fault repair turbine hydropower stationAbstrac

11、t: with the progress of society, the rapid development of economy, peoples living standard has been greatly improved, peoples water use gradually increased. In hydropower into more and more families, failure of turbine hydropower station requires the relevant officers on the spot inspection, diagnos

12、is and troubleshooting. Because of the turbine generator structure more complicated mechanical part, electrical part and the oil, gas, water system which was influenced by the system and the user mode of operation is also affected by the weather and other natural conditions. Prone to failure or abno

13、rmal operation state. A fault may be an accident but to the whole unit operation is an inevitable event. The operating personnel from thought, organization, technology and other aspects fully prepared. The hydroelectric power station generating units and repair of common trouble. Keywords: common fa

14、ult repair turbine hydropower station一 Common faults of electric part of a Hydropower StationThe generator in the process of operation, due to the impact and own, generator parameters will change, and may exceed the normal operating permit. A short period of time more than parameters specified opera

15、ting or exceed the specified operating parameters not does not have serious consequences, but the long-term than operating parameters or over a range of operating parameters are likely to cause serious consequences, crisis and the safety of the generator should be paid attention to. 1, the generator

16、 overloadOperation of the generator, when the stator current exceeds the rated value of 1.1 times, over load protection action signal generator. Operating personnel should be treated, using its normal operation. If the system is not failure occurs, you should first decrease excitation current decrea

17、ses from the generator without power; if the system is low voltage and to ensure the power factor requirements, while reducing the excitation current is still not using stator current drop back to the rated value, only the small generator load; if the system fails, allowing the generator overload op

18、eration in a short period of time, which allows the value according to the manufacturers operation.2, the generator rotor one point groundGenerator rotor grounding one point grounding and two-point grounding, rotorground can also be divided into instantaneous grounding, permanent ground, intermitten

19、t grounding.Generator rotor one point grounding, the grounding point does not form a loop, no current through the fault point, the excitation system can still working, but the rotor one point ground will change the rotor to ground voltage and the negative to positive voltage, may cause the rotor two

20、 points grounding fault; and then causes the rotor unbalanced magnetic pull, causing vibration and causes the rotor to fever.3, the rotor circuit two-point groundingGenerator rotor two grounding points, due to the formation of the loop, the current through the fault point.4, the generator temperatur

21、e too highThe generator is in operation, if the stator, rotor or core temperature exceeds the specified value, should be timely inspection5, the generator stator groundingGenerator stator grounding means of generator stator winding single-phase circuit is directly connected with the stator winding c

22、ircuit or a system grounding. Stator grounding into instantaneous grounding, permanent ground, intermittent grounding.二、 Common faults of mechanical part two, hydropower station1, the strong vibration is a common fault in the hydraulic turbine, which is not easy to catch, to eliminate hidden dangers

23、 of accidents, not only affect the normal operation of turbine units, but also reduce the service life of machine and spare parts. 2, hydraulic turbine cavitation is the main reason of turbine damage, the damage degree has become the key parameters to determine whether an overhaul, due to cavitation

24、 will directly reduce the economic benefit and the safety of the turbine unit. 3, with the hydraulic turbine proportion in the whole power system is more and more big, the annual average generation time prolonged, the maintenance time is shortened, once by accident, cause the economic loss is very s

25、erious. In addition, the power grid dispatching of more and more emphasis on peak regulation role of hydroelectric generating units, for the full use of hydropower plant is the maximum output.4, in recent years the design practice of hydropower unit of high head, high speed, high efficiency, large c

26、apacity in the trend of the use of high strength materials, component is more flexible, just increase the size and unit of, will bring more stabilityproblems三、 Fault diagnosis fault diagnosis method of power unit three, hydropower station1, generating setFirst look .A look at the. Diagnosis of gener

27、ator unit, first of all need to repair of turbine appearance, to determine the type, age, condition and need repair position. The generator production date and clearly marked production date, which can accurately judge the use fixed number of year, experienced repair personnel even in the observatio

28、n generator using condition, we can find that the fault lies.Two listen. Repair personnel according to the fault generator power station staff to understand the specific situation, such as the generator failure of performance, type of generator, maintenance and use of habits. In a power station staf

29、f exchanges, carefully remember fault staff described and fault location, in order to make accurate repair plan, understand the maintenance status in deep conversation, can give the power station put forward good suggestions and opinions, so that after the repair of hair Motor maintenance.In the inq

30、uiry, repair personnel basically confirmed the position and the cause of the trouble. Experienced hydropower station staff to provide information basically accurate, thus avoiding unnecessary repair personnel to the generator checks, save time and manpower. Even if the work experience is not very ri

31、ch, through conversation can also determine the basic failure condition, get some useful information. There are many reasons for the generator failure, the specific parts such as power supply system, mechanical system of power plant, water diversion system of generator and other electric control sys

32、tem, may cause the generator cant work. To repair without asking the staff situation, will feel unable to start, out of chaos, through the staff to talk, understand the generating units to start difficult phenomenon, when HERSHEYS bad, failure occurred mostly occur in the turbine is used for a perio

33、d of time out after ten minutes, through the understanding of conditions and the phenomenon the fault can be ruled out as a cause, basically point unit mechanical system, through the use of hydropower station staff communication, quickly eliminate fault, to ensure normal operation of generating unit

34、s.The turbine generator unit fault causes many years are related with the use, use a period of time after many failures follow close on succession, some seeminglyinsignificant failure, do not seem to affect the normal work of the power unit, but after repair personnel check will find these faults, t

35、hese risks can not be.2 the use of special instruments generator equipment diagnosisEquipment diagnosis method is the use of professional testing equipment, tools and instruments to detect a generating unit structure, technical condition (such as clearance, vibration frequency, acoustic, infrared) m

36、ethod of waveform to diagnosis of turbine. The improvement and development of instrument and equipment, the fault can be accurately on the generator to make the correct diagnosis, and analysis of the causes of failure, on-line detection of fast and accurate.Use of modern detection technology, measur

37、ing instruments and equipment to complete the test task specific integrated testing system, plays an important role in the modernization of detection and diagnosis of generator unit fault. Such as the use of turbine development technology of virtual instrument detection system, generator unit fault

38、diagnosis of computer analysis system, turbine performance test and fault diagnosis system.四、 Common fault of generator four, hydropower station and repairFor those common fault of generator existing hydropower station, power station operators should take effective measures, the common fault prevention generator. In order to make the generator set to work, should advance control for turbine hydropower st