永磁电磁轴承磁力的两种线性化方法

针对控制系统模型的实际应用需要，对永磁电磁轴承的磁力提出了两种线性化方法。运用设计实例对这两种方法进行了验证，获得了较好的近似结果。最后分析了各自的特点，所研究的问题对永磁电磁轴承的设计有一定的指导意义。     

Measurement of transient neutral gas puff pressure in the NUDT_IPPTx by a fast ionization gauge

A gas injector was designed for the 400 J/pulse prototype of the planar inductive pulsed plasma thruster (IPPT) developed by the National University of Defense Technology (NUDT_IPPTx). As the gas puff distribution over the coil surface is critical to the NUDT_IPPTx functioning efficiently, a fast ionization gauge was developed to investigate the neutral gas pressure profiles to seek the critical time when the thruster is ignited. The gauge was calibrated for argon by using a capacitance manometer. Time-resolved pressure profiles have been acquired in the condition of the gas puff mass matching with the discharge energy and the drive coil parameters of the NUDT_IPPTx. It is demonstrated that the gas injector can supply a gas puff with a sufficiently steep (d_p/d_t ≈ 770 kPa s^-1 ) leading and trailing edge, and the gas puff can be compressed against the drive coil as expected. The critical ignition moment is considered to appear at some instant between 525 μs and 650μs after the valve trigger.     

永磁电磁轴承的磁路设计方法

通过对永磁电磁轴承磁路设计过程的系统分析，提出了一种混合磁轴承工程磁路设计方法。文中详细给出了设计中各环节的计算方法和需要考虑的因素，并以具体设计实例加以验证说明。本文所提出的磁路设计方法对混合磁轴承的设计有重要的参考意义。     

Analysis of the Plasma Properties Affected by Magnetic Confinement with Special Emphasis on Helicon Discharges

A one-dimensional radial non-uniform fluid model is employed to study plasma behaviors with special emphasis laid on helicon discharges. The plasma density ne, electron temperature Te, electron azimuthal and radial drift velocities are investigated in terms of the plasma radius rp, magnetic field intensity B0 and gas pressure p0, by assuming radial ambipolar diffusion and negligible ion cyclotron movement. The results show that the magnetic confinement plays an important role in the discharge equilibrium, especially at low pressure, which significantly reduces Te compared with the case of a negligible magnetic field effect, and higher B0 leads to a greater average plasma density. Te shows little variations in the plasma density range of 1011 cm-3- 1013 cm-3 for p0 〈 3.0 mTorr. Comparison of the simulation results with experiments suggests that the model can make reasonable predictions of Te in low pressure helicon discharges.     

磁悬浮动量轮动力学模型研究

运用拉格朗日方程,建立了磁悬浮动量轮系统径向平动的精确动力学模型,并以应用广泛的PD控制进行了运动分析。研究表明,两自由度径向磁轴承的径向平动方向存在一定的耦合运动,但藕合对运动妁影响甚微,实际控制中可以采用单自由度运动模型替代。这方面的研究对认识磁悬浮动量轮的运动特性有积极的作用。     

电磁轴承结构参数设计研究

以实际工程应用为背景,针对电磁轴承的结构参数设计,分析了忽略铁磁材料磁阻对磁路计算带来的误差。通过对控制器参数的研究,表明磁轴承最终的控制刚度不仅与控制器有关,而且受结构参数的制约。从提高控制线圈电流和磁力的响应速度出发,给出了工作气隙、磁极面积与控制线圈的设计原则。这些结构参数与控制性能相关性的研究对于提高电磁轴承的总体性能有积极的作用。     

运载器控制系统CAN总线数据传输仿真与评估研究

针对CAN总线连接的运载器控制系统方案,建立了控制系统总线数据传输仿真平台。该平台以部件等效器模拟控制系统内各种敏感器和执行机构,通过CAN总线与以太网连成网络;采用CAN总线仿真工、具CANoe建立总线数据流测试与评估节点。利用该平台仿真了运载器从发射到入轨飞行过程中控制系统总线上的数据传输状态,对总线性能、信号周期和数据传输可靠性等进行了分析,结果表明CAN总线可以满足运载器控制系统数据传输要求。     

利用ANSYS软件进行磁悬浮动量轮的磁场设计

首先介绍了通用有限元软件ANSYS的一般功能。然后讲述了利用ANSYS软件对磁悬浮动量轮的磁场进行数值计算的一般步骤，详细描述了从创建物理环境到解后处理的全过程。最后以磁悬浮动量轮这一设计实例作为说明。对于利用ANSYS进行磁场分析研究有一定的参考意义。     

微型卫星激光推进发射概念与影响因素研究

建立了大气吸气模式与火箭模式组合的激光推进运载器（光船）发射微小卫星入轨的系统概念和分析模型，考虑了推进系统性能、大气传输衰减、模式转换高度、激光器功率、大气飞行阻力、发射点高度等因素对发射系统性能的影响，并对光船发射轨迹进行了计算和讨论。     

Numerical simulation and performance analysis of the radiofrequency inductive cathode

The radiofrequency(RF) inductive cathode has great prospects in space missions with long mission cycles, large speed increments, and rapid response requirements as the main electron source and neutralizer in Hall thrusters and ion thrusters. This paper proposes a comprehensive multi-physics RF inductive cathode model in which the RF electromagnetic field, electrostatic field for extracting electrons, flow field, plasma transport and electrochemical reaction process are all accounted for. Each ph...