谐波电流对同步发电机温升的影响分析

摘要

小容量发电机组为非线性负荷供电时，大量的谐波电流会流过同步电机的定子电枢绕组。在趋肤效应和邻近效应的影响下，高频谐波电流无法均匀分布在绕组导线截面上，而是沿绕线边缘传导。这增大了同步发电机的绕组电阻，引起发电机发热增加，效率降低，容量减小。分析谐波流经同步发电机定子绕组时趋肤效应和邻近效应的作用原理，用有限元分析软件Maxwell对电流在绕组截面上的分布规律进行仿真研究，并将绕组近似等效为若干个电感线圈，得到一种对谐波电流发热功率的估算方法。%Lots of harmonic currents will flow through the armature winding of the stator of synchronous generator when power supply is provided for non-linear load by generator set with small capacity. Under skin effect and proximity effect, the high frequency harmonic current is not evenly distributed on the cross-section of conductor, but transmits along the winding edge, resulting in increases of winding resistance and heat of generator, efficiency and capacity reduction. The paper analyzes the action principle when the harmonic current flows through armature winding of the stator of synchronous generator, conducts the simulation study on distribution rule of current on winding cross-section with finite element analysis software Maxwell and obtains an estimation method for heating power of harmonic current by making the windings equivalent to several inductance coils.