【作者】 雷美珍；

【导师】 戴文战；

【作者基本信息】 浙江理工大学 ， 机械工程， 2014， 博士

【摘要】 直线振荡执行器是一种无需中间机械转换部件即可实现高频往复直线运动的执行机构,其具有机械结构简单、噪音小、响应速度快和系统效率高等优点,适用于驱动制冷压缩机、电磁泵、人工心脏和振动筛等设备。动磁式结构直线振荡执行器由于动子质量轻、振荡频率高和推力密度高等优点得到日益广泛的重视,但结构复杂、内定子叠装困难和加工工艺要求高等一直是制约其发展的关键问题。对此,本文首次提出一种无需内定子的直线振荡执行器,并对其若干关键问题进行深入的分析与研究。本文的主要研究成果如下:(1)首次提出一种无需内定子的动磁式直线振荡执行器拓扑结构在分析现有各种拓扑结构的基础上,首次提出一种无需内定子的动磁式直线振荡执行器的新结构。新结构采用间隔一定距离的两个对称“C”型外定子,动子永磁体位于两个“C”型齿中间,具有无需内定子、结构简单、加工方便、漏磁小、电磁推力密度高和电磁推力可控性好等优点。(2)执行器的等效磁路建模及三维有限元分析在分析该直线振荡执行器运行原理的基础上,建立其等效磁路模型,采用虚功法推导出电磁推力和电感的解析计算公式。为准确分析其磁场分布和电磁特性,建立了结构尺寸参数化的三维有限元模型,计算了气隙磁链和电磁推力的电流和位移特性,分析了永磁体尺寸等多个关键参数对执行器输出电磁推力和有效行程的影响。(3)执行器的设计方法及多目标优化分析了该直线振荡执行器设计的基本方法,结合等效磁路法和三维有限元分析法推导出执行器关键参数的设计依据及解析公式。针对该动磁式直线振荡执行器需综合电磁推力较大和永磁体体积较小的要求,结合表面响应模型法和量子行为粒子群算法对执行器的永磁体尺寸进行多目标优化,克服了等效磁路优化模型计算精度低和三维磁场模型计算效率低的不足,同时避免了传统粒子群算法可能陷入局部最优解的问题。有限元结果验证了优化结果的正确性并表明,采用该方法优化后的执行器相比优化前输出电磁推力提高了 6.2%,永磁体体积减小了12.8%。(4)执行器机电系统谐振特性分析及等效机械谐振频率跟踪控制以驱动压缩机负载为例,建立集机械动力系统和电磁系统一体化的等效数学模型。在此基础上采用矢量法分析系统谐振特性,并推导出效率和功率因数等重要性能指标的解析计算公式。为实现等效机械谐振频率跟踪,提出一种基于改进扰动观察法的最大功率点跟踪方法。仿真结果证明,改进算法能加快其等效机械谐振频率跟踪速度,降低其在最大功率点附近的功率振荡,较好实现该执行器在变工况条件下的等效机械谐振频率跟踪。(5)执行器动子位移自传感算法研究提出一种基于全维状态观测器的执行器动子位移自传感算法,该算法通过端电压和电流的处理和计算来估算动子位移。仿真和实验结果表明,该算法能实现不同运行频率下的动子位移自传感,实测行程估算绝对误差的最大值为0.32 mm,相对误差的最大值为2.6%。针对直线振荡执行器在运行过程中等效电阻参数摄动问题,提出一种带等效电阻辨识的自适应动子位移观测器,推导出基于李雅普诺夫稳定性的自适应律。仿真结果表明,该算法能较好抑制等效电阻参数变化引起的动子位移观测误差。(6)样机实验研究在理论分析和设计的基础上,实际加工了一台实验样机,并设计了一套基于DSP的性能测试平台。样机的测试结果与理论分析结果吻合良好,证明本文提出的新结构、所建模型和理论计算均是正确,体现该新型执行器具有较高研究价值和应用前景。更多还原

【Abstract】 Linear oscillatory actuator(LOA)is an electromagnetic driving device which is able to achieve high reciprocating linear motions without intermediate conversion mechanism.It has the merits of simple structure,low noise,fast response and high efficiency,etc.The actuator has been widely used to drive refrigeration compressors,pumps,artificial hearts and shakers.The moving-magnet LOA has becoming more and more important in LOA areas due to its light mover mass,high resonant frequency and high thrust density.However,the key issues which restrict the development of LOA are complicated structure,difficulty in inner stator stacking and high production cost.A novel LOA with no inner-stators was proposed,and in-depth analysis of some key issues of it xwas carried out.The content of this paper is organized as following:(1)A novel LOA with no inner-stators was first proposedBy analyzing various topologies of the existing LOAs,a novel moving-magnet LOA with no inner-stators was first proposed.The novel topology has two symmetry"C" type external divided stators with separation distance,and the mover is set between two "C" type teeth.It has the characteristics of compact configuration,easy manufacture,little flux leakage,high electromagnetic thrust density and good thrust controllability.(2)Magnetic equivalent circuit modelling and 3D finite element analysis(FEA)The principle of the novel LOA with no inner-stators was analyzed,and the magnetic equivalent circuit model of it was established.Then the analytical expression of electromagnetic thrust and inductance were derived via virtual work method.3D parametric FEA model of the novel LOA was established to calculate the flux distribution and electromagnetic thrust.The effects of permanent magnet(PM)dimensions and other key parameters on the performance of the novel LOA were also analyzed.(3)The design methodology and multi-objective optimization of the novel LOAThe design methodology of the novel LOA was analyzed,and the design criteria of the critical parameters and analytic formulas were derived via magnetic equivalent circuit method and 3D FEA.In order to meet the requirements of relative maximum thrust and relative minimum volume,a novel multi-object optimization method by combining the response surface model(RSM)and quantum-behaved particle swarm optimization(QPSO)was proposed to optimize the PM dimensions.The novel optimization method overcomes the shorages of low accurary of equivalent magnetic circuit optimization model and low calculation efficiency of 3D magnetic field model calculations,and avoids the problem which the traditional particle swarm optimization(PSO)method may fall into local optimal solution.The FEA results validates the correctness of the optimized results.After optimization,the thrust of this novel actuator was increased by 6.2%,and its volume was decreased by 12.8%.(4)Resonant frequency characteristics analysis and equivalent mechanical resonant frequency tracking control of the novel LOABased on driving the compressor load,equivalent mathematical model including mechanical system and electromagnetic system was proposed.The resonant frequency characteristics of this actuator was analyzed via vector methods,and the analytic formulas of critical performance such as efficiency and power factor were derived.A mechanical resonant frequency tracking control strategy based on improved perturbation and observation method was proposed.Simulation results showed that the improved algorithm is effective to accelerate the resonant frequency tracking velocity and reduce the power oscillations at the maximum power point.Research indicates that the mechanical resonant frequency tracking control under the variable load was realized and the efficiency was improved by the proposed algorithm.(5)The mover displacement self-sensing algorithm for the novel LOAThe mover displacement self-sensing algorithm for the novel LOA was established based on full-dimensional state observer.The simulation and experimental results showed that its mover displacement was estimated by calculating and processing its voltage and current under various frequency.The maximum absolute error of estimate stroke is 0.32mm,and the maximum relative error is 2.6%.An adaptive full-dimensional mover displacement observer was proposed based on equivalent resistance identification,and the adaptive law was deduced based on lyapunov.Research indicates that the proposed algorithm is able to restrain the observation errors caused by the changes in resistance parameters.(6)The protype experimental research of the novel LOAAn experimental prototype of the novel LOA was proposed,and the SPWM drive control system based on DSP was implemented.The experimental results of electrical performance verified the correctness of the design methodology,mathematical model and theoretical calculations.It also proved that this novel LOA has high research value and application prospects.更多还原