MW级双并列转子低速永磁直驱电机设计方法与性能分析

Design method and performance analysis of MW-level dual-parallel rotor low-speed permanent magnet direct-driven motor

针对二辊式轧机、双螺杆泵等并行同步对驱类设备存在体积庞大、主从动轴同步性差且需要定期维护等问题,提出一种双并列转子永磁电机直驱系统,整个传动系统更加紧凑高效。结合工程需求,构建了双并列转子永磁直驱电机的基本结构,定义了双并列转子永磁电机定子耦合区内的设计关键参数,并基于等效磁路法对耦合区磁路分布进行了分析,从定子分块规则和冲片几何结构的角度出发,建立了耦合区内耦合角的确定方法。对一台额定功率为1 200 kW、额定转速为20 r/min的双并列转子永磁直驱电机进行了电磁设计,通过数值仿真对所设计的电磁方案进行了校核分析,探讨了占空角大小对转矩脉动和转子所受不平衡电磁力的影响,为双并列转子永磁直驱系统的研发奠定了基础。

Aiming at the problems of two-roll mill,twin-screw pump and other parallel synchronous drive equipment,such as bulky volume,poor synchronization of master and slave shafts,and the need for regular maintenance,a dual-parallel rotor permanent magnet motor direct-driven system was proposed,making the entire transmission system more compact and efficient.Based on engineering requirements,the basic structure of the dual-parallel rotor permanent magnet direct-driven motor was constructed,and the design key parameters in stator coupling area of dual-parallel rotor permanent magnet motor were defined.The magnetic circuit distribution in the coupling area was analyzed based on the equivalent magnetic circuit method.The method for determining the coupling angle in coupling area was established from the perspective of the partitioning principle of the stator and the geometrical structure of the punching piece.The electromagnetic design was carried out for a dual-parallel rotor permanent magnet direct-driven motor with a rated power of 1200 kW and a rated speed of 20 r/min,and check analysis of the motor were carried out through numerical simulation.The influence of duty angle on torque ripple and unbalanced electromagnetic force of rotor was also discussed,which lays a foundation for the research and development of dual-parallel rotor permanent magnet direct-driven system.