抽水蓄能发电电动机电磁场三维有限元分析

发电电动机是抽水蓄能电站的核心部分,其运行时涉及的电磁、机械、散热等问题十分复杂,是一个多物理场耦合分析问题,其中电磁场分析是基础。以广州抽水蓄能B厂某发电电动机为例,采用三维有限元法对其进行电磁场计算,建立了发电电动机的三维模型,分析了电流密度、磁场分布和气隙磁密的分布情况。结果表明,定子绕组电流和励磁绕组电流大小符合电机在满载运行时的情况;磁极处磁密最大,槽齿处磁密也较大,轭部和相邻两磁极交界处的磁密较小;气隙磁密沿轴向的大小不是恒定值,由于端部漏磁通的影响,靠近端部的气隙径向磁密小于轴向中心处。

Electromagnetic Field Analysis of Pumped Storage Generator-Motor Using Three-dimensional Finite Element Method

Generator-Motor plays an important role in pumped storage power station. Electromagnetic, mechanical and heat dissipation problems are very complex and it is a multi-physical field coupling problem whose electromagnetic analysis is the foundation. Taking generator-motor of Guangzhou B pumped storage power plant for an example, three-dimensional finite element method is used to calculate electromagnetic field. A 3-D generator-motor model is established and the distribution of current density, magnetic field distribution and gap flux density are analyzed. The results show that the current of stator winding and excitation winding are accord with the full load operation situation of the generator-motor. The magnetic density of pole has the maximum value. The magnetic density of cogging has a relatively large value. The value of magnetic density in yoke and the region between the two poles are relatively small. The air gap flux density in the axial direction is not a steady state value. The radial air gap flux density near the end is smaller than that of the axial center for the influence of leakage magnetic flux in the end because of the end leakage flux.