电磁-温度-应力耦合作用下新型复合式磁力耦合器三维漏磁机理研究

Aiming at the problems of heavy load, severe wear and serious pollution in harsh coal mine environment, a new type of composite magnetic coupler with cutting the magnetic induction line through the axis and the radial conductor is proposed, which could achieve the increase of magnetic force. Focus on the interaction region of the axis and radial magnetic field of the composite magnetic coupler, the dynamic characteristics and three-dimensional magnetic leakage mechanism of the composite magnetic coupler under the action of electromagnetic-temperature-stress are studied by means of theoretical analysis, numerical simulation and experiment. The air gap magnetic field model of the composite magnetic coupler is established by using the equivalent magnetic circuit method, then the quantitative rules of the parameters and dynamic characteristics of the composite magnetic coupler are pursued. A three-dimensional electromagnetic-temperature-stress coupling model is constructed to realize real-time and accurate coupling between heat loss and temperature field stress field, then the variation of temperature stress with time and spatial distribution characteristics of components are obtained. Based on the region integral method, the permeability of the magnetic leakage loop in the interaction region of the axial and radial magnetic fields is analyzed, and the three-dimensional magnetic leakage mechanism under the electromagnetic-temperature-stress coupling is revealed. Finally, the small prototype is trial-produced for the transmission test of the composite magnetic coupler under electromagnetic-temperature-stress coupling, which could correct the prototype and provide the scientific basis for energy-saving transmission of mechanical system with severe wear and frequent overload in harsh environment of coal mine.

针对重载启动、磨损剧烈、污染严重等煤矿环境下机械系统的传动节能问题，提出了一种新型的复合式磁力耦合器，可通过轴、径向导体同时切割磁感应线实现磁场力的增大。针对复合式磁力耦合器轴、径向磁场的交互区域，以理论分析、数值模拟及试验为主要研究手段，研究电磁-温度-应力作用下复合式磁力耦合器的动态特性以及三维漏磁机理。采用等效磁路法，建立复合式磁力耦合器的气隙磁场模型，探求复合式磁力耦合器参数与动态特性的量化规律；构建三维电磁-温度-应力耦合模型，实现热源损耗与温度场应力场实时精确耦合，得出各部件温度应力随时间的变化，以及空间分布特性；基于区域积分法，分析轴、径向磁场的交互区域漏磁回路的磁导，揭示电磁-温度-应力耦合作用下的三维漏磁机理；试制小型样机，开展电磁-温度-应力耦合作用下复合式磁力耦合器的传动试验并修正样机，为煤矿恶劣环境下磨损严重与经常性过载工作的机械系统节能传动提供科学依据。

紧密联系煤矿工程需求，开展电磁-温度-应力耦合作用下复合式磁力耦合器的结构设计以及三维漏磁机理研究。主要研究工作与结论如下：.1）考虑漏磁效应，建立了复合式磁力耦合器等效磁路网络模型，由此得到了漏磁系数的计算公式；采用三维有限元法仿真复合式磁力耦合器的漏磁系数，并将其与漏磁系数的计算值相比较，平均误差仅为8.7%；分析了四个漏磁参数α、β、γ及η在总漏磁中所占权重，结果显示：相较于复合漏磁α，其余三个漏磁数值较小；漏磁系数计算值、三维有限元分析值与试验值之间吻合较好；与忽略气隙漏磁效应的情况相比，考虑气隙漏磁分析计算后的复合式磁力耦合器输出转矩值与试验值更接近，计算值更精确。.2）根据新型复合式磁力耦合器的结构特点，应用化“场”为“路”的方法，建立了气隙磁场的计算公式；基于电流叠加性，将电流折算到铜导体表面，并沿圆周方向对感生电动势进行积分，建立了空间磁场的输出转矩模型。当转差率相同时，理论值、仿真值及试验值三者之间的差距小于10%；在同等体积条件下，相较于普通双盘式磁力耦合器，复合式磁力耦合器传递的扭矩增大了30.7%；与配备相同容量异步电机的矿山机械相比，配备复合式磁力耦合器的矿山机械的线性工作区域较宽，机械特性较软，因此过载保护能力更强。.3）针对复合式磁力耦合器在三维磁场仿真中忽略了涡流热量对输出转矩计算的影响，提出了一种基于永磁磁场-温度耦合场的三维有限元分析方法，分析涡流热量对铜导体与永磁体性能的影响，将涡流产生的热功率作为热源载荷依次导入Transient Thermal模块的温度场，再将温度场的仿真结果修正复合式磁力耦合器的性能参数。研究结果显示，计算值与试验值之间吻合较好，应用永磁磁场-温度场耦合分析方法能够准确地分析复合式磁力耦合器温度分布。