
In this paper, the boundaryvalue problem of rotor negativesequence eddy current field and its numerical solution by the finite element method(FEM) are discussed. A variational formulation is presented and the existence and uniqueness of the solution are proved. On application of FEM to the above stated boundaryvalue problem, a method for formulating the discrete equation and some related formulas are given in detail. The convergence of this method is proved, and a block diagram for programming is given.... In this paper, the boundaryvalue problem of rotor negativesequence eddy current field and its numerical solution by the finite element method(FEM) are discussed. A variational formulation is presented and the existence and uniqueness of the solution are proved. On application of FEM to the above stated boundaryvalue problem, a method for formulating the discrete equation and some related formulas are given in detail. The convergence of this method is proved, and a block diagram for programming is given. As an example, the distributions and losses of negativesequence eddy current in rotor are calculated by FEM for SQF75275 MW turbogenerator. As the calculating results are compared with those of practical tests, thier close agreement is satisfactory. The effect of different wedge materials and mesh sizes on results of calculation is also discussed. 本文讨论了负序涡流场边值问题及其有限元解法，文中给出了问题的变分形式，证明了解的存在唯一性；给出了应用于该问题的有限元法离散方程的形成方法和公式，证明了方法的收敛性，给出了程序框图。文中还以 ＳＱＦ－７５－２ ７５兆瓦汽轮发电机为例，用有限元计算了转子负序涡流分布和损耗，计算结果与现场试验比较，基本符合，并讨论了不同槽楔材料、网格大小对计算结果的影响。 The equation of eddycurrent induced in the alternating magnetic fields in a rectangular thin plate is derived from the principle of electric eddycurrent excite by the application of the fundamental theorem of electromagnetism. The data of eddycurrent fields are obtained by electronic computers. The equivalent excitationforce and the appropriate position of the actingpoint are found. This work is very useful for the design adjustment and application of the... The equation of eddycurrent induced in the alternating magnetic fields in a rectangular thin plate is derived from the principle of electric eddycurrent excite by the application of the fundamental theorem of electromagnetism. The data of eddycurrent fields are obtained by electronic computers. The equivalent excitationforce and the appropriate position of the actingpoint are found. This work is very useful for the design adjustment and application of the exciter. 本文从电涡流激振器的原理出发,运用电磁学基本定理导出了矩形金属薄板在给定交变磁场中感应的涡流方程,并用电子计算机解出电涡流场的数据,可计算等效激振力和作用点位置。这些工作对涡流激振器的设计、调试和使用都是很重要的。 This paper describes the test methods and the various test results for the deter mination of the negative sequence current capability of type QFQ502 turbogenerator by equivalent loss method.The current of the rotor slot wedges are measured by mag netic test coils,and the eddycurrent field of the rotor are calculated by finite ele ment method.By the comparison of the calculation results with the measured values, the accuracy of the calculating methods is satisfactory. 本文介绍了应用等效损耗法确定 QFQ502型汽轮发电机负序电流能力的试验方法和结果。试验中用“磁带”测量了转子槽楔电流,并用有限元法计算了转子涡流场。计算结果与实测值进行对比,证明了计算方法的准确性。 



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