4/8极无刷双馈电机的转子绕组设计

Rotor Winding Design Method of 4/8 Pole Brushless Doubly Fed Machine

在变速恒频发电和变频调速等应用领域,采用无刷双馈电机加变频器的方案有着很多的优点,如变频器容量小、系统效率高、可靠性高等。无刷双馈电机的转子采用绕线转子结构具有谐波含量小、成本低、设计方法灵活等优点,容易做到使两种极对数的绕组磁势均为正弦形。本文提出了一种基于磁势叠加原理的绕线转子无刷双馈电机的转子绕组设计方法,该方法采用一套绕组"重复利用"的方式得到了两种不同极数且旋转方向相反的磁势。该方法可以实现这两种极数转子磁势幅值的任意比,从而为优化设计提供了可行性。本文研究了转子绕组的两个优化设计原则:转矩密度最大原则和转子铜耗最小原则,分析了转子铁耗和电磁振动问题。在此基础上设计了一台64 k W的4/8极绕线转子无刷双馈发电机并进行了实验研究。实验结果证明了所提出设计方法的正确性。

In many application field such as variable speed constant frequency generator system and variable speed drive system, the system of Brushless Doubly - Fed Machine （BDFM） has great advantages such as the small capacity of inverter, high efficiency, and high reliability. The BDFM with wound rotor structure has many advantages such as small harmonic content and low cost. And it is easy to make two rotor MMF waveform of BDFM to be sinusoid. A novel design method of wound rotor based on MMF superposition principle was presented in this paper. This method can obtain two different MMF waveforms with two different pole pairs number and the opposite rotating direction by way of a winding ＂recycling＂. The ampli- tude ratio of two MMF waveforms can be design to be any value according to the proposed method, which provides the feasibility for the optimization design. Two design principles： the principle of maximum torque density and the rotor copper loss minimization are studied in this paper. The rotor ferrite loss and electromag- netic vibration were studied in this paper, too. Based on these design result, a 64 kW 4/8 pole wound rotor brushless doubly fed generator was made and studied experimentally. The correctness of the proposed design method was proved by experimental results.