Modeling and analysis of oil frictional loss in wet-type permanent magnet synchronous motor for aerospace electro-hydrostatic actuator

To improve the power density and simplify the seal structure,the Wet-Type Permanent Magnet Synchronous Motor(WTPMSM)technique has been applied to aerospace Electro-Hydrostatic Actuators(EHA).In a WTPMSM,the stator and the rotor are both immersed in the aviation hydraulic oil.Although the heat dissipation performance of the WTPMSM can be enhanced,the aviation hydraulic oil will cost an extra oil frictional loss in the narrow airgap of the WTPMSM.This paper proposes an accurate oil frictional loss model for the WTPMSM,in which the wide speed range(0–20 kr/min)and the narrowness of the airgap(0.5–1.5 mm)are its features.Firstly,the mechanism of the oil frictional loss in the airgap of the WTPMSM is revealed.Then an accurate oil frictional loss model is proposed considering the nonlinear influence caused by the Taylor vortex.Furthermore,the influence of motor dimensions on oil frictional loss is analyzed.Finally,the proposed oil frictional loss model is verified by experiments,which provides a guideline for engineers to follow in the WTPMSM design.

Solenoid Actuator Design for Improvement of Response Speed

The main design factors which effect on operating speed of solenoid actuator for valve operation are mass of plunger, electromagnetic motive force, inductance and return spring, and these factors are not independent but related with each other in view point of design and electromagnetic theory. It is impossible to increase the operating speed by only change the value of any one design factor. The change of any one value results in change of any value related it in various design factors. Permanent magnets are as assistant materials which make higher flux density in air gap. Electromagnetic motive force in controlled only by current. This paper presents a speed increasing design method of solenoid actuator using a solenoid, by some governing equations which are composed of electromagnetic theory and empirical knowledge, and proved the propriety by experiments.

Characteristic investigation of permanent magnet actuator for vacuum contactors operating with an intrinsically safe low voltage

This paper reports a new application of permanent magnet actuator for vacuum contactors.A novel permanent magnet(PM) actuator to drive a vacuum contactor with intrinsically safe and low supply voltage is proposed.PM is mounted on the static iron of the contactor to enhance its holding force and reliability.While only one coil is used to break the vacuum contactor,two series coils are deployed to yield a high magnetomotive force to realize the making operation.The electrical circuit equation,mechanical equation and magnetic field are all coupled in the simulation.A prototype is manufactured and tested to validate and showcase the performance of the contactor which is equipped with the proposed PM actuator.

直驱型机电作动器建模与动态特性分析

机电作动器作为飞行控制系统的关键执行机构,其性能对系统输出动态响应具有重要影响.根据直驱型机电作动器的结构组成,建立包含永磁同步电机控制和行星滚柱丝杠非线性因素的系统仿真模型.研究了“i_(d)=0”电流矢量控制下的系统阶跃响应,结果表明:基于永磁同步电机三闭环伺服控制策略的系统在不同位置阶跃信号指令下均具有良好的动态性能.通过与文献的对比,表明该控制策略下的机电作动器仿真模型有效.

Magnetic Actuation Systems and Magnetic Robots for Gastrointestinal Examination and Treatment

Magnetic actuation technology(MAT)provides novel diagnostic tools for the early screening and treatment of digestive cancers,which have high morbidity and mortality rates worldwide.The application of magnetic actuation systems and magnetic robots in gastrointestinal(GI)diagnosis and treatment to provide a comprehensive reference manual for scholars in the field of MAT research are reviewed.It describes the basic principles of magnetic actuation and magnetic field safety,introduces the design,manufacturing,control,and performance parameters of magnetic actuation systems,as well as the applicability and limitations of each system for different parts of the GI tract.It analyzes the characteristics and advantages of different types and functions of magnetic robots,summarizes the challenges faced by MAT in clinical applications,and provides an outlook on the future prospects of the field.

模块化多电平换流阀子模块用真空旁路开关设计

模块化多电平换流阀(MMC)子模块的可靠性直接影响到柔性直流输电系统的整体稳定性,旁路开关是决定子模块关断性能的关键设备之一。文中基于永磁机构的工作原理和理论建立一种双线圈旁路开关模型,利用仿真分析电容储能电压、电容值、线圈线径和匝数以及弹簧参数对开关动态特性的影响规律,并对其动态特性进行优化设计。最后根据仿真结果制作样机并进行试验验证,测试结果表明:旁路开关满足在3 ms内合闸,零弹跳的技术要求,且通过雷电冲击试验、工频耐压试验、方波电压试验3项绝缘试验。

集成式电机主轴的力感知及微进给特性研究

为满足精密加工过程中对电机主轴的转速、进给距离和切削力精确控制的需求,将永磁同步电机和超磁致伸缩驱动器结合,提出一种具有转动、微进给及力感知功能的集成式电机主轴。为验证集成式电机主轴力感知部分的结构合理性,基于磁路法和有限元分析法,得出集成式电机主轴的微进给距离、外线圈感应电压与外部载荷的关系。最后,为验证仿真的准确性,搭建集成式电机主轴力感知及微进给试验平台。结果显示,在此磁路模型设计中,集成式电机主轴的磁通密度可达0.551 9 T,磁通密度均匀度大于77.85%,集成式电机主轴的微进给距离可达26.5μm,外线圈感应电压与外部载荷成反比且内线圈的最佳外加电流为5 A。研究结果表明,集成式电机主轴力感知及微进给功能的设计是合理可行的,为深入研究和精确控制集成式电机主轴奠定了基础。

全电式水下阀执行器多电机协同控制策略研究

水下采油树全电执行器多电机协同工作时,由于误差等导致减速器发生振动。为了减少同步误差导致传动系统发生振动的情况,通过对多电机协调策略进行研究,从控制算法层面提出了一种基于改进粒子群算法优化模糊PI补偿器的多电机协同控制策略。使用Logistic混沌映射并结合中心耦合游移的策略改进粒子群算法,采用改进后的算法离线优化模糊控制器的隶属度函数。为了得到最小的同步误差,在适应度评价函数中引入同步误差项。为了验证该方案,建立了Simulink/Adams联合仿真模型,在Adams中以轴套力柔性连接替换理想约束,建立了联合仿真模型和传动机构动力学模型,对传动机构的振动情况进行了仿真。研究结果表明,该方法通过减小同步误差,能有效减轻传动系统的振动情况。所得结论可为多电机协同控制提供参考。

Design Optimization and Comparison of Linear Magnetic Actuators under Different Topologies

In this study,several types of linear actuators that adopt different permanent-magnet(PM)topologies are studied and compared.These linear actuators are based on the concept of PM magnetic screw transmission,which offers high force density,high reliability,and overload protection.Using different magnetic configurations and assembly methods,these linear actuators are designed and optimized for a fair comparison.Initially,based on the operating principle and maximum thrust force,the surface-mounted magnetic screw is described and optimized.Furthermore,the embedded magnetic screw,Halbach array magnetic screw,and field modulated magnetic screw are investigated and compared.Their electromagnetic performances,such as thrust force,torque,magnetic losses,and demagnetization effects are analytically assessed and verified using finite-element analysis.Finally,a prototype of the surface-mounted magnetic screw is developed to validate the predictions.

基于集成学习方法的机电作动器故障诊断框架

针对飞行器综合性能不断提高的发展需求,对机载机电作动器(EMA)进行健康管理尤为关键。文章以EMA作为研究对象,重点研究基于集成学习方法的故障诊断框架来解决飞行器可能存在的健康管理问题:对比不同集成学习策略间的优劣,提出一种以Boosting集成学习方法为核心的故障诊断框架。该方法的建立以XGBoost、LightGBM和CatBoost模型为基础,相较于时下流行的深度学习框架,其占用的计算资源更少,模型的可解释性更强。试验结果表明,该框架相较于传统机器学习方法准确率提高10%,相较于深度学习方法训练时间减少75%,且内存占用率更低,具有较强的工程应用价值。

航空永磁电驱动系统比例谐振型自抗扰速度控制器设计

襟缝翼机电作动器是飞机高升力系统中的关键运动部件,其速度控制对襟缝翼的姿态调节十分重要。然而,襟缝翼机电作动器易受到翼面周期性或非周期性气动载荷干扰,传统的比例积分型速度控制器性能实现受限。为此,本文提出一种基于比例谐振自抗扰控制器(ADRC),在抑制非周期性干扰基础上还可抑制特定次周期性干扰。周期性干扰通过采用比例谐振控制的扩展状态观测器来估计。通过试验,比较了比例积分型控制器、传统线性自抗扰控制器和比例谐振型自抗扰控制器的控制性能,验证了本文所提出的方法可以显著抑制干扰、提高机电作动器的速度控制精度,为飞机平稳起降提供技术支撑。

混合叠压圆筒型永磁直线振荡电机电磁特性分析

圆筒型双定子永磁直线振荡电机因其结构简单、功率密度高而广泛应用于压缩机领域。然而,电机的定子通常采用传统的硅钢片周向叠压方式,导致其叠压系数低、磁路易饱和。因此,该文提出一种新的混合叠压方法。首先,介绍了双定子永磁直线振荡电机的基本拓扑结构和工作原理,给出磁路特有的分布方式;然后,对采用电工纯铁和硅钢片混合叠压方式进行分析,推导了硅钢片数量与电工纯铁之间的占比关系,并对不同硅钢片数量对电机反电动势、电磁推力和损耗的影响进行分析;最后,通过三维有限元分析对采用传统叠压方式和混合叠压方式的双定子永磁直线振荡电机的电磁特性进行了比较和分析。实验结果验证了混合叠压方式在提高电磁推力和简化制作工艺方面的优势。

基于模糊PID控制的准零刚度磁悬浮隔振平台的设计与实现

为有效降低系统固有频率,获得外部振动在多频段的强衰减,以永磁电磁混合作动器为负刚度结构提出并设计了一种准零刚度的磁悬浮隔振平台,实现了基于模糊PID(proportional integral differential)算法的振动主动控制系统.首先,通过特性分析与参数计算,基于准零刚度理论完成了准零刚度磁悬浮隔振平台的方案设计;其次,建立磁悬浮隔振系统模型,提出基于模糊PID算法的振动主动控制策略,可主动调节系统的等效刚度和阻尼;最后,基于Speedgoat实时目标机开发振动主动控制系统,搭建隔振测试平台,并开展了隔振性能测试.研究结果表明:本文设计的准零刚度磁悬浮隔振平台通过采用模糊PID的控制策略能够主动调节PID参数,动态调整系统的等效刚度和阻尼;外部振动频率在20~100 Hz频率段内,振动衰减率大于80%;外部振动频率在100~500 Hz频率段内,振动衰减率大于90%.

配永磁机构真空断路器操动时间分散性的预测模型与影响因素研究

针对现有模型存在的难以实现多场充分耦合的问题,提出了一种对配永磁机构真空断路器动作时间进行预测的新模型。该模型考虑励磁变化和运动部件速度效应带来的涡流影响,实现了永磁操动机构的复杂机械运动、电子瞬态电路与瞬态磁场的多场耦合分析。基于该模型,对某型号配永磁机构真空断路器的动作时间进行了预测,实验证明所提方法是正确的。在此基础上,利用模型分析了励磁电压、环境温度、铁心材料和励磁方式等因素对永磁操作机构动作时间分散性的影响,并研究了各因素对动作时间分散性的影响机理。

一种永磁辅助开关磁阻电机的四区间DITC方法

与传统开关磁阻电机相比,永磁辅助开关磁阻电机有更高的功率密度和效率、更大的转矩安培比,但存在较大的转矩脉动,限制了工程应用范围。该文首先解释传统直接瞬时转矩控制策略,针对传统直接瞬时转矩控制策略转矩脉动的原因,提出一种将两相交换区细分为交换Ⅰ区、交换Ⅱ区和交换Ⅲ区,与单相导通区构成一个电周期的四区间,分别给出与区间电感特性相适应的滞环控制;然后提出不同转速下的导通角算法,建立自适应导通角的四区间转矩脉动抑制方法。最后以一台三相6/20的永磁辅助开关磁阻电机为例,进行仿真分析和样机实验。结果表明,该方法能在宽转速范围上有效降低永磁辅助开关磁阻电机的转矩脉动。

A novel fault tolerant permanent magnet synchronous motor with improved optimal torque control for aerospace application

Improving fault tolerant performance of permanent magnet synchronous motor has always been the central issue of the electrically supplied actuator for aerospace application. In this paper, a novel fault tolerant permanent magnet synchronous motor is proposed, which is character- ized by two stators and two rotors on the same shaft with a circumferential displacement of mechanical angle of 4.5°. It helps to reduce the cogging torque. Each segment of the stator and the rotor can be considered as an 8-pole/10-slot five-phase permanent magnet synchronous motor with concentrated, single-layer and alternate teeth wound winding, which enhance the fault isola- tion capacity of the motor. Furthermore, the motor has high phase inductance to restrain the short-circuit current. In addition, an improved optimal torque control strategy is proposed to make the motor work well under the open-circuit fault and short-circuit fault conditions. Simulation and experiment results show that the proposed fault tolerant motor system has excellent fault tolerant capacity, which is able to operate continuously under the third open-circuit fault and second short- circuit fault condition without system performance degradation, which was not available earlier.

三相对称绕组的多自由度磁性致动器设计

针对基于机械弹簧的多自由度致动器存在系统复杂、运动精度低的问题,设计了一种采用铁氧体永磁体的新型谐振致动器。首先,所提致动器的基本结构主要包括1个定子、1个动子和1个三相对称绕组,其中动子部分包括6个永磁铁氧体和1个动铁芯;其次,对磁阻特性和推力特性进行了理论研究;然后,在动力学模型分析的基础上,提出了无需位置传感器的运动估计方法;最后,通过有限元分析验证了所提致动器的特性,并与样机上的测量结果进行了比较。研究结果表明:样机的磁阻力误差和力常数误差分别仅为6%和2%,且在无机械弹簧的条件下产生相对于移动距离的对中力,从而可以在X-Y平面上实现各种可控的高精度谐振运动。所提致动器有效降低了系统成本和复杂性,可用于需要精确受控运动的机械领域,在微型机器人、医疗设备和光学仪器等。

双余度差速作动系统用永磁式制动器的设计

为满足双余度差速作动系统工作切换和故障隔离的要求,提出了一种永磁式制动器,并给出了制动器的组成和工作原理。通过等效磁路法建立了锁定和解锁状态制动器的解析模型,并与有限元分析结果进行了对比。进行了制动器摩擦副的设计,分析了摩擦副的磁性能和摩擦性能。最后将制动器实验结果与分析结果进行了比较,验证了分析结果的准确性。

新型12 kV真空断路器单稳态永磁机构的设计

高速发展的电力系统要求电力故障在更短的时间内切除,而传统的永磁断路器难以达到要求。以ZW32-12型户外交流高压真空断路器为原型,设计了一款三相独立运动的单线圈单稳态永磁机构,每相永磁机构内置分闸弹簧、励磁线圈及永磁体,与真空灭弧室通过绝缘拉杆直接相连,采用的直线运动方式使其在体积、功耗、性能等方面都有所改善。