多跨距无刷双馈电机转子绕组设计及特性分析

Rotor design and characteristic analysis of brushless doubly-fed machine

针对无刷双馈电机谐波大,效率低的问题,基于齿谐波原理和不等匝绕组理论,提出一种基于混合式转子结构的多跨距复合式的无刷双馈发电机转子设计方案,这一具有磁阻效应的混合式转子绕组结构能有效的提高转子导体利用率,提高无刷双馈电机功率绕组的输出功率,并能显著降低与无刷双馈电机两种主要基波极对数相近的谐波含量,对于降低无刷双馈电机绕组谐波含量提高整机效率提供了参考。最后以一台450 kW电机为例具体介绍了多跨距复合式转子绕组的设计方法,并通过建立有限元模型进行具体分析,通过与双正弦绕组的无刷双馈电机在磁场分布,气隙磁密谐波情况及电机输出功率的对比分析,结果表明多跨距复合式转子结构的无刷双馈电机具有良好的整机性能。

In order to solve the problem of large harmonics and low efficiency of brushless doubly-fed machine,based on the tooth harmonic principle and unequal turn winding theory,this paper proposes a multi span compound rotor design scheme of brushless doubly-fed generator based on hybrid rotor structure.The hybrid rotor winding structure with magnetoresistive effect can effectively improve the conductor utilization rate,increase the output power of the power winding,and significantly reduce the harmonic content similar to the two main fundamental poles pairs.It provides a reference for reducing the harmonic content of brushless doubly fed machine winding and improves the efficiency of the whole machine.Finally,taking a 450 kW motor as an example,the design method of multi-span composite rotor windings was introduced in detail.By establishing a finite element model,the brushless doubly-fed machine with double sinusoidal windings was analyzed in detail.The comparative analysis of magnetic field distribution,air gap magnetic density harmonics and motor output power shows that the brushless doubly-fed machine with multi-span composite rotor structure has good performance.