开关磁阻电机磁固耦合非线性动力学建模及振动控制

As one of the most potential, energy-saving and efficient electric machines, switched reluctance motors (SRMs) have important values to be researched and application prospect to be popularized. However, vibration and noise are the major serious problems to restrict the application of SRMs for a broad speed regulation area. In the study, based on the electro-mechanical dynamic theory, a method with combining Maxwell-stress and magnetic circuit methods is used to calculate the air flux distinity between stator and rotor poles. And then, a nonlinear dynamic model considering the coupled reaction between the radial displacement of stator and radial electromagnetic force is built, where the saturation effects of magnetic material and the fringe flux effects are also considered. On the basic modeling, two strategies of vibration reduction are presented. First, the improved multiple-object genetic algorithm is used to optimize the structure of SRMs, which can reduce the radial force effectively from the design point of view. Second, a composite control strategy with Fuzzy control and ADRC is used to optimize the wave forms of phase current and implement the reversal compensation control between torque and current, where the phase current can vary with the reference current for obtaining a stable output torque and minimum torque ripple. With torque ripple reduction, the uncertainty problem caused by load interfering and parameter variation is restrained. The availability and effectiveness of the model and the vibration control can be verified by 3D finite element simulations and experiments. For SRMs, there is important theoretic significance in this study, which will be useful and actual for advancing the operational performance and broadening the application in high precise servo and drive control areas of this machine.

开关磁阻电机作为一种最具潜力、高效节能的机电一体化产品，具有重要的研究价值和推广应用前景。振动和噪声是目前制约开关磁阻电机应用于更广泛调速领域的主要原因。本项目基于机电分析动力学理论，考虑铁磁材料的饱和特性与边缘磁通的影响，结合麦克斯韦应力法与磁路法对定转子凸极间的气隙磁密和电磁力进行计算，建立考虑定子径向振动位移与电磁力耦合作用的非线性动力学模型。在此基础上，一方面，利用改进多目标遗传算法对开关磁阻电机进行结构优化设计，使径向力降到最低；另一方面，通过模糊控制技术实现转矩电流的逆向补偿控制，获得优化的参考电流值，采用改进自抗扰控制技术使相电流实时跟踪参考电流变化，得到平稳的转矩输出，在降低转矩脉动的同时克服系统中因负载扰动及参数变化引起的不确定性。模型和振动控制的有效性通过仿真和实验来验证。本项目研究对提高电机的运行性能和扩大其在高精度伺服驱动控制领域的应用具有重要的理论意义和实用价值。

开关磁阻电机作为一种最具潜力、高效节能的机电一体化产品，具有重要的研究价值和推广应用前景。本项目围绕引起电机振动和噪声的转矩脉动问题、磁固耦合建模以及控制策略进行了相关研究。基于机电分析动力学理论，考虑了铁磁材料的饱和特性与边缘磁通的影响，结合麦克斯韦应力法与磁路法对定转子凸极间的气隙磁密和电磁力进行了计算，建立考虑定子径向振动位移与电磁力耦合作用的非线性动力学模型。建模过程中，考虑了开关磁阻电机位移场与电磁场相互影响，利用麦克斯韦张量法和磁路法，推导了开关磁阻电机定子系统所受径向电磁力模型。将定转子间气隙长度变化量耦合到定子凸极的径向电磁力函数中，再结合梁函数组合法解得定子系统径向振动位移的表达式，充分反映了电机结构变化和气隙磁场、电磁力变化的定量对应关系。在此基础上，一方面，利用改进多目标遗传算法对开关磁阻电机进行结构优化设计，使径向力降到最低；通过对选定开关磁阻样机进行了有限元电磁力学计算和分析，研究了转子斜槽结构对电机的静态磁链和转矩特性的影响，并进行了斜槽结构设计前后结果的对比。分析表明，转子斜槽结构可有效改善电机平稳运行性能，对转矩脉动具有一定的抑制作用，主要是由于转子斜槽会使定转子凸极之间有一定的重合，得到的磁链曲线与直槽时的磁链相比在非对齐的位置有所增加，完全对齐的位置有所减少，使得整个曲线更为平滑。另一方面，通过模糊控制技术实现转矩电流的逆向补偿控制，获得优化的参考电流值，采用改进自抗扰控制技术使相电流实时跟踪参考电流变化，得到平稳的转矩输出，在降低转矩脉动的同时克服系统中因负载扰动及参数变化引起的不确定性。仿真和实验基本验证了模型和振动控制策略的有效性。本项目研究成果有助于提高开关磁阻电机的运行性能和扩大其在高精度伺服驱动控制领域的应用范围。