It is important to monitor the radial loads in hydropower units in order to protect the machine from harmful radial loads. Existing recommendations in the standards regarding the radial movements of the shaft and bearing housing in hydropower units, ISO-7919-5 (International Organization for Standardization, 2005, “ISO 7919-5: Mechanical Vibration—Evaluation of Machine Vibration by Measurements on Rotating Shafts—Part 5: Machine Sets in Hydraulic Power Generating and Pumping Plants,” Geneva, Switzerland) and ISO-10816-5 (International Organization for Standardization, 2000, “ISO 10816-5: Mechanical Vibration—Evaluation of Machine Vibration by Measurements on Non-Rotating Parts—Part 5: Machine Sets in Hydraulic Power Generating and Pumping Plants,” Geneva, Switzerland), have alarm levels based on statistical data and do not consider the mechanical properties of the machine. The synchronous speed of the unit determines the maximum recommended shaft displacement and housing acceleration, according to these standards. This paper presents a methodology for the alarm and trip levels based on the design criteria of the hydropower unit and the measured radial loads in the machine during operation. When a hydropower unit is designed, one of its design criteria is to withstand certain loads spectra without the occurrence of fatigue in the mechanical components. These calculated limits for fatigue are used to set limits for the maximum radial loads allowed in the machine before it shuts down in order to protect itself from damage due to high radial loads. Radial loads in hydropower units are caused by unbalance, shape deviations, dynamic flow properties in the turbine, etc. Standards exist for balancing and manufacturers (and power plant owners) have recommendations for maximum allowed shape deviations in generators. These standards and recommendations determine which loads, at a maximum, should be allowed before an alarm is sent that the machine needs maintenance. The radial bearing load can be determined using load cells, bearing properties multiplied by shaft displacement, or bearing bracket stiffness multiplied by housing compression or movement. Different load measurement methods should be used depending on the design of the machine and accuracy demands in the load measurement. The methodology presented in the paper is applied to a 40 MW hydropower unit; suggestions are presented for the alarm and trip levels for the machine based on the mechanical properties and radial loads.
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机译：重要的是，监视水力发电机组中的径向负载，以保护机器免受有害的径向负载。有关水电单元中轴和轴承座径向运动的标准中的现有建议，ISO-7919-5（国际标准化组织，2005年，“ ISO 7919-5：机械振动—通过旋转轴的测量来评估机器振动） —第5部分：水力发电厂和抽水厂的机器，瑞士日内瓦，ISO-10816-5（国际标准化组织，2000年，ISO 10816-5：机械振动-通过非振动测量评估机械振动） -旋转零件-第5部分：水力发电和抽水厂的机器，瑞士日内瓦，）具有基于统计数据的警报级别，并且未考虑机器的机械性能。根据这些标准，设备的同步速度决定了建议的最大轴位移和壳体加速度。本文根据水力发电机组的设计标准以及在运行过程中机器中测得的径向载荷，提出了一种报警和跳闸等级的方法。在设计水力发电机组时，其设计标准之一是承受一定的载荷谱而不会在机械部件中出现疲劳。这些计算出的疲劳极限用于设置机器停机之前允许的最大径向载荷极限，以保护自身免受高径向载荷造成的损坏。水力发电机组中的径向负载是由不平衡，形状偏差，涡轮机中的动态流动特性等引起的。存在平衡的标准，制造商（和电厂所有者）对发电机的最大允许形状偏差提出了建议。这些标准和建议确定在发出需要维护机器的警报之前，最大应允许哪些负载。径向轴承载荷可以通过称重传感器，轴承特性乘以轴位移或轴承支架刚度乘以轴承座压缩或运动来确定。根据机器的设计和负载测量的精度要求，应使用不同的负载测量方法。本文介绍的方法适用于40 MW的水力发电机组。根据机械性能和径向负载，提出了有关机器的警报和跳闸级别的建议。
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