多极多层式磁流变离合器基础理论及控制方法研究

Torque density and torque range are the problems to be solved urgently in the field of magnetorheological (MR) transmission. Based on the theories and methods of electromagnetics, thermodynamics, fluid dynamics and control, the theoretical and experimental researches on the basic principles and control methods of a novel multi-pole multi-layer MR clutch are carried out. A new type of MR clutch based on the principle of superposition of two magnetic fields generated by the inner coil and the outer coil is proposed, and the magnetic circuit model is established by using the principle of electromagnetics. Based on the fluid dynamics and the rheological properties of MR fluid under the individual input current, a dynamic model of MR clutch is established. According to the characteristics of several coils, the optimal control index is determined as the maximum output torque and the lowest energy consumption under a given structural volume, and the output torque and energy consumption are limited to a certain allowable range. The optimal control method is studied with the control strategy of optimal control theory. The dynamic characteristics of the MR clutch are studied on the test bench, and the effectiveness of the control method is verified by the simulation platform. The objective of the project can not only provide theoretical guidance for the research of MR clutch, but also promote the development of MR technology.

转矩密度、转矩范围是目前磁流变传动技术是亟待解决的问题，本项目综合运用电磁学、热学、流体动力学和控制学的理论和方法，对多线圈独立式新型多极多层式磁流变离合器的基本原理与控制方法进行理论和实验研究。提出一种基于内线圈产生的和通过外线圈产生的两磁场叠加原理的新型磁流变离合器；利用电磁学原理，建立新型磁流变离合器的磁路模型；利用流体动力学原理，并结合磁流变液在多线圈独立供电作用下的流变特性，建立新型磁流变离合器的动力学模型；针对多线圈特点，将控制的优化指标定为在给定结构体积下的输出力矩最大且能耗最低，将输出力矩和能耗限制在某个允许范围之内，结合最优控制理论的控制策略，研究最优控制方法。在试验台架上研究磁流变离合器的动态特性，利用仿真平台验证多线圈控制方法的有效性。本项目研究不仅对多极磁流变离合器的发展提供理论指导，同时对磁流变技术的进步起到推动作用。

本项目以多极式磁流变离合器为研究对象，开展高转矩密度、宽转矩范围的结构紧凑型磁流变离合器研究。首先分析了多线圈叠加的多极式磁流变离合器的磁场叠加效果和磁路模型。进一步地，为了简化结构、改善密封以及减小能源消耗，用永磁体代替部分线圈，设计了两种永磁体和线圈组合式磁流变离合器，同时研究了永磁体形状对间隙磁场强度的影响。最后完成了两种基于永磁体和线圈的多极多层式磁流变离合器的结构设计、原理样机研制、模拟仿真和控制方法研究，在搭建的磁流变离合器测试平台上开展了输出特性和控制实验。研究结果表明，在永磁体和线圈产生的两个磁场的叠加作用下，磁流变离合器的输出力矩可以增加；输出力矩与永磁体的磁场强度、形状等相关；输出力矩的动态响应受到测试系统和控制方法的影响。本项目研究对永磁体和线圈组合式磁流变离合器的研究具有重要意义，为磁流变离合器的推广应用提供了基础。