为使汽轮发电机轴流风扇产生的气动摩擦损耗不直接引入到电机内部,研制了大容量350MW抽风式空冷汽轮发电机.基于该电机在试验条件下轴流风扇安装角为29.2°的运行数据,开展CFD仿真计算,研究扇叶的安装角(29.2°、31.2°)和叶片数对静压效率、压升、温升等风扇性能参数的影响.通过数据分析发现,在保证风扇数目足够的情况下,电机风量较大时,可采用风扇安装角度31.2°,同时适当提高空冷器冷却能力;在电机风量较少时,建议采用风扇安装角29.2°.

以某汽轮发电机导电杆为研究对象,分别采用热网络法、有限元法和电-热耦合计算的方法,对其温升情况进行研究.文中最后采用电-热耦合的方法,无需给定损耗源的大小,而是通过设置流入导体的电流值,采用耦合计算的方法对导电杆温升进行计算,减小了损耗计算方法带来的误差.更为准确的通过比较三种方法的各自特点,指出了电-热耦合法的优点,得出耦合法是今后的发展趋势.

This paper presents the features of ventilation system,cooling method and the choice of heating parameters of Xiluodu hydro generator.The air flow rate of the ventilation system is calculated with network method,and the temperature distribution in each part is calculated with finite element method.By analyzing the results,the baffle is installed to improve the distribution of air flow rate,which put forward the optimization of the local flow field.In addition,the influence of ventilation system structure on the ventilation cooling effect is discussed.The results show that the test data and the calculation results is very close to each other,the improving method is benefit to the cooling effect.

以一台7 800 kW发电机为研究对象,该电机主机、励磁机采用相通的风路进行冷却,根据电机结构及损耗分布情况,采用FLOWMASTER软件对该电机的主机和励磁机的通风进行了计算,并分别对主机和励磁机的温升进行了研究.在计算结果基础上对结构进行优化,保证其散热能力满足机组运行要求.

以1500MW核电半速大型发电机的转子通风系统为例,通过对副槽多段轴径向通风结构进行设计,并利用所需风量小的优势,提出了;种针对副槽多段轴径向通风结构的转子温升计算方法.

The structure of air-cooled 20MW synchronous motor is compact,whether the ventilation system is designed reasonable or not greatly impacts the temperatures of stator,rotor and end part of the electric machines.In this paper,the temperature rise in each part is studied with the method of air paths and temperature distribution.By simulation analyzing to the air paths and heat generation parts, the affect of ventilation and the temperature rise of major part are provided.

Ventilation system of 150MW air cooled turbogenerator was computed and analyzed in detail in this paper.Thermal network method was used to create the networks and calculate temperature rise of stator and rotor.The ventilation test on the turbogenerator was performed,including air flow rate,fan efficiency,pressure and so on.The results were quite close to the calculated values.The ventilation system and coolers can meet the requirements of the endurance,security and reliablity of the electric machine operation.

Firstly,this paper creates physical model according to fluid mechanics theory and fluid similarity theory.Secondly,taking a pumped storage power generating unit as an example,it applies research method of similar ventilation model to verify the correctness of mathematics modeling method for calculating the wind resistance of each part of a real machine through experimentation.At last,it is proved that the ventilation system design of the real machine is feasible and reasonable.

In this paper,the characteristics of ventilation system and the fluid state of the air flow of 700MW hydrogenerator are simulated by means of studying similitude ventilation model,which is useful for varifying the feasibility of the ventilation system design and improving the structure of ventilation system.

本文叙述了灯泡式水轮发电机通风系统的特点,探讨了如何通过调整通风系统结构来保证风量沿轴的均匀分配,介绍了计算电机风量的网络法及计算定、转子各部分温度分布的有限元法,以便在此基础上进行通风系统进一步改进.

本文针对万家寨水轮发电机转子温升偏高的问题进行了通风系统改造,使其达到有效降低温升、降低通风损耗的目的.

本文应用流体动力分析软件FLOWMASTER及ANSYS有限元分析软件研究了交流电动机通风系统和定子三维温度场,形成了一套计算交流电动机风量分配及三维温度分布的研究方法.

本文给出了实际运行中的大型发电机用冷却器裕度实用判别法--冷风温度判别法,同时给出了准确的冷却器非正常工况的计算法--工作点计算法,并给出了与原有计算法的对比计算.

旋涡起主导作用的流动是当前世界前沿的研究领域之一.磁极极间的旋涡流动十分复杂,包含的物理内容也很丰富,一些流动现象、机理和规律还不完全清楚,采用数值模拟并结合风洞试验技术进行深入研究,对于理论探讨和实际工程应用都具有重要意义.应用人工压缩性方法求解了二维定常不可压雷诺平均Navier-Stokes方程,应用了Beam-Warming近似因子分解格式及其对角化形式,以及Baldwin-Lomax代数湍流模型,对水轮发电机通风系统流场进行了数值模拟.