在ESS中嵌入滤波器实现转子电场恒速的系统设计方法

对于空心大球转子静电陀螺仪,转速接近静电支承系统(ESS)的剪切频率,一般采用磁场恒速控制方法,因而介绍了一种电场恒速控制方法,通过在支承电路中加入滤波器,来提高支承系统的力矩系数,从而利用支承系统构成了恒速控制系统。实验结果表明,系统的稳定性满足要求,恒速精度优于0.1Hz。     

球形转子的精密恒速控制系统

讨论了静电支承球形转子的精密恒速控制系统，该系统主要基于旋转磁场加转和锁相控制。阐述了控制系统的组成，分析了鉴相器、PD控制、加转系统模型并加以线陛化，求出传递函数并分析特性，最后介绍了具体实验效果。     

静电支承球形转子的恒速控制

本讨论静电支承球形转子的恒速控制问题。首先,介绍静电支承系统的基本工作原理,其次,建立静电支承系统的动力学模型。第三,分析采用PID控制器的支承刚度,第四,阐述形成静电旋转力矩的原理。最后,提出利用静电力恒速的方案与基本限制条件。     

一种小型静电陀螺仪三位一体系统方案

在比较了国外两种小型静电陀螺仪方案的基础上，研究了一种小型静电陀螺仪质量不平衡调制信号读取、数字式支承和电场恒速三位一体工作系统方案。介绍了三位一体系统的工作原理，讨论了系统各组成模块的功能，对制约系统性能的关键因素作了相关分析。分析表明，在抵消变压器线圈阻抗匹配的条件下，可以忽略加力和信号读取之间的相互影响。     

基于可控式被动阻尼的静电陀螺仪启动控制系统

静电陀螺仪(ESG)的启动阻尼是一个转子最大惯性主轴与转轴对准的过程。采用直流磁场的可控式被动阻尼方法有效地解决了转子极性倒置问题。中介绍了基于可控式被动阻尼ESG启动控制系统的设计和研制，该系统以浮点DSP芯片TMS320C32为核心电路，具有转子阻尼、极性识别与控制、故障检测、转速测定、恒速控制和RS232通讯等功能。在气浮装置上证实了所研制的系统能有效实现上述功能。     

小型静电陀螺仪转子变形及干扰力矩分析

推导了小型静电陀螺仪转子非球形干扰力矩公式，仿真分析了两种不同结构的实心转子的温度变形、离心变形、压力变形及综合变形，计算了其变形产生的干扰力矩及漂移。     

静电悬浮转子微陀螺及其关键技术

静电悬浮转子微陀螺具有比振动式微陀螺精度高的潜在优点，并可同时测量二轴角速度和三轴线加速度。介绍了静电悬浮转子微陀螺的研究现状。对该静电悬浮转子微F1螺／加速度计的工作原理、特点进行了分析，并对实现高精度静电悬浮转子微陀螺／加速度计晌关键技术如静电稳定悬浮、微位移检测控制、静电恒速旋转驱动、微机械加工和真空封装技术等进行了探讨。指出这一新颖MEMS陀螺是高精度多轴集成微惯性传感器技术发展的一个重要方向，具有广阔的应用前号和较大的发展潜力。     

静电陀螺仪用光纤传感器实验研究

以静电陀螺仪用光纤传感器原理样机为基础，开展了信号拾取的实验研究。基于球形模拟转子的实验表明，该光纤传感器能够满足静电陀螺仪极轴信号拾取的灵敏度要求。文中分析了影响光纤传感器信号拾取性能的相关因素，设计了光纤准直器的有关参数，提出了光纤传感器小型化的设想，为光纤传感器的实用提供了参考。     

静电陀螺仪MUM小角度读取的相关技术研究

讨论了同步解调法实现静电陀螺仪质量不平衡调制（MUM，Mass-Unbalanced Modulation）小角度读取的原理，分析了影响读取分辨率的各种因素，并对其实施方案中的相关技术进行了探讨。研究表明，尽管MUM读取方案非常适用于实心转子静电陀螺仪，但前提是将其小角度读取的分辨率提高到可与光电方法相比的水平（角秒级）。要实现这一目标，首先要保证转子和电极的机械特性达到一定要求；在此基础上，还要在支承系统的结构、转子位移测量电路设计等方面进行精心设计。     

静电陀螺转子位移测量电路的研究

—静电陀螺转子位移测量电路是静电陀螺支承系统的重要部件。它直接影响转子在电极球腔中的失中度，从而导致陀螺漂移。因此在温度变化及电磁干扰情况下，必须提高测量电路的分辨率和零位稳定性。本文在理论分析和实验研究的基础上，提出参数优化设计方法和模块化结构设计。实验结果表明所研制的电路性能良好，工作稳定度达到了高精度静电陀螺仪的要求。     

变转速共轴旋翼载荷建模及实验验证

对共轴双旋翼无人飞行器操纵结构的简化,会引起旋翼载荷变化更加复杂。共轴双旋翼转速控制方法有助于飞行控制系统的实现,但是在飞行控制律设计时,需要透彻了解变转速旋翼的气动载荷变化,建立精准的旋翼载荷模型。本文深入分析了旋翼变转速情况下单旋翼系统和共轴双旋翼系统的旋翼入流分布,建立了单旋翼变转速旋翼载荷计算方法,提出了共轴双旋翼变转速旋翼载荷计算方法。明确了低雷诺数对微型旋翼飞行器的旋翼载荷计算影响,引入雷诺数修正系数完成对旋翼翼型升阻系数气动参数的修正和验证,提高了变转速共轴双旋翼载荷模型的计算精度。设计了一套变转速单旋翼系统和共轴双旋翼系统的旋翼载荷测量实验装置,通过实验测试完成了对共轴双旋翼载荷计算方法的验证,表明了所提出的变转速共轴双旋翼载荷模型和实验测试装置是可信的。     

八电极静电陀螺支承系统的建模

八电极静电支承系统沿着四个非正交轴对转子施加静电力,这些作用力相互影响,因此需要对支承坐标进行垂直解耦。针对采用八电极方案的静电陀螺,给出了电极电容的计算公式和位移解算方法,推导了静电力计算公式,最后建立了八电极静电陀螺支承系统的模型并利用Simulink对系统进行仿真。仿真结果表明,在系统中加入解算矩阵和"3-4"变换矩阵后,可以使X、Y、Z三个轴向上对转子位移的控制相互独立,为转子的可靠支承奠定了基础。     

变速转子准稳态主动平衡系统的增益调度控制

在现代高速旋转机械中,不平衡引起的振动是机器性能降低甚至损坏的重要原因。对变速转子准稳态主动平衡系统,可按一定时间步长把变转速离散成有限个转动角速度。针对每个离散角速度,依据影响系数法,采用包含残余振动值和校正不平衡的广义线性二次型目标性能函数推导出控制律。通过每个离散转速下影响系数的估计和增益矩阵的计算,形成对应于各离散转速的增益表,从而实现变速转子准稳态主动平衡系统的增益调度控制。数值模拟验证了增益调度控制能很好地抑制不平衡振动。与传统的加权二乘法(WLS)相比,数值模拟显示,该法对校正不平衡的惩罚可提高系统的稳定性,也可增强控制的鲁棒性。     

Optimization of the rotor surface resistance of the asynchronous electrostatic motor

For an electrostatic motor consisting of a rotor of insulating material covered with a slightly conducting surface layer, and a ring of electrodes fed with phase-shifted ac voltages that generate a rotating electric field acting on the rotor, the maximum torque on the rotor and the corresponding surface resistance are determined theoretically under the condition that the amplitude of the ac voltages on the electrodes is constant.     

电动桥式起重机负载升降过程的系统动力学模拟

从系统的角度考虑电动桥式起重机起升机构工作过程中的动力学模拟问题。首先,由系统的拉格朗日函数、约束条件和电机的磁共能定义修正的拉格朗日函数;随后,应用Hamilton原理和三相感应电机瞬态模型得出起升机构工作过程中电动桥式起重机系统的运动方程。为验证模型的效果,本文还进行了转子串电阻速度控制系统控制下的32t电动桥式起重机吊运额定负载下降过程的数值模拟,分析了高速浮动轴扭转刚度以及制动过程中转子电阻的配置方案对系统动力响应的影响。模拟结果表明,制动过程中起升机构高速浮动轴所受载荷远大于起动过程中所受载荷,制动开始时在电机转子电路中增加一级较大的外串电阻有利于减小下降制动阶段系统中的动载。     

A note on internal damping induced self-excited vibration in a rotor by considering source loading of a DC motor drive

It is well known that rotors become unstable beyond a certain threshold spinning speed due to the non-conservative circulatory forces, which arise out of rotating internal damping. In this note, it is shown that if the source loading of the non-ideal drive is considered then this instability manifests itself as a constant rotor spinning speed and a constant amplitude whirl orbit about an unstable equilibrium. A DC motor drive is considered and the corresponding steady-state spinning frequency and whirl orbit amplitude are analytically derived as functions of the drive and the rotor system parameters.     

Magnetic field effects on the nonlinear vibration of a rotor

The nonlinear vibration of a rotor operated in a magnetic field with geometric and inertia nonlinearity is investigated. An asymmetric magnetic flux density is generated,resulting in the production of a load on the rotor since the air-gap distribution between the rotor and the stator is not uniform. This electromagnetic load is a nonlinear function of the distance between the geometric centers of the rotor and the stator. The nonlinear equation of motion is obtained by the inclusion of the nonlinearity in the inertia, the curvature, and the electromagnetic load. After discretization of the governing partial differential equations by the Galerkin method, the multiple-scale perturbation method is used to derive the approximate solutions to the equations. In the numerical results, the effects of the electromagnetic parameter load, the damping coefficient, the amplitude of the initial displacement, the mass moment of inertia, and the rotation speed on the linear and nonlinear backward and forward frequencies are investigated. The results show that the magnetic field has significant effects on the nonlinear frequency of oscillation.     

Dynamic analysis of a tethered satellite system with a moving mass

This paper presents a dynamic analysis of a tethered satellite system with a moving mass. A dynamic model with four degrees of freedom, i.e., a two-piece dumbbell model, is established for tethered satellites conveying a mass between them along the tether length. This model includes two satellites and a moving mass, treated as particles in a single orbital plane, which are connected by massless, straight tethers. The equations of motion are derived by using Lagrange’s equations. From the equations of motion, the dynamic response of the system when the moving mass travels along the tether connecting the two satellites is computed and analyzed. We investigate the global tendencies of the libration angle difference (between the two sections of tether) with respect to the changes in the system parameters, such as the initial libration angle, size (i.e. mass) of the moving mass, velocity of the moving mass, and tether length. We also present an elliptic orbit case and show that the libration angles and their difference increase as orbital eccentricity increases. Finally, our results show that a one-piece dumbbell model is qualitatively valid for studying the system under certain conditions, such as when the initial libration angles, moving mass velocity, and moving mass size are small, the tether length is large, and the mass ratio of the two satellites is large.     

裂纹转子在支承松动时的振动特性研究

以具有支承松动的Jeffcott裂纹转子为研究对象，分析了支承松动和轴上横向裂纹对转子系统刚度的影响，建立了转子系统振动的微分方程，并用数值方法分析了其振动特性。分析表明，转子在裂纹和支承松动这两种非线性因素的作用下，表现出复杂的非线性行为。     

On the dynamics of the fluid balancer

This paper is concerned with the dynamics of a so-called fluid balancer; a hula hoop ring-like structure containing a small amount of liquid which, during rotation, is spun out to form a thin liquid layer on the outermost inner surface of the ring. The liquid is able to counteract unbalanced mass in an elastically mounted rotor. The paper derives the equations of motion for the coupled fluid–structure system, with the fluid equations based on shallow water theory. An approximate analytical solution is obtained via the method of multiple scales. For a rotor with an unbalance mass, and without fluid, it is well known that the unbalance mass is in the direction of the rotor deflection at sub-critical rotation speeds, and opposite to the direction of the rotor deflection at super-critical rotation speeds (when seen from a rotating coordinate system, attached to the rotor). The perturbation analysis of the problem involving fluid shows that the mass center of the fluid layer is in the direction of the rotor deflection for any rotation speed. In this way a surface wave on the fluid layer can counterbalance an unbalanced mass.