压缩机测试系统工况控制策略的研究

在研究压缩机测试系统试验工况之间的数学关系基础上，针对控制系统的硬件选择。提出了一种以D／P转换为核心，用条件概率为描述语言的概率控制技术。将简单的开关控制转变为全波的调压式控制。在测试系统的工况控制中概率控制技术使控制系统有了较高的动静态性能。     

不同工况下刮板输送机启动时的动力学特性研究

根据不同工况下刮板输送机系统的承载特性,利用有限元法构建了刮板输送机系统的动力学模型,对不同工况下刮板输送机系统在启动时的动力学特性进行了分析,为优化刮板输送机系统的启动控制系统、提升刮板输送机工作时的稳定性和可靠性、降低断链事故发生的概率提供理论基础。     

汽车真空辅助制动系统的设计与研究

以汽车紧急制动工况为研究对象,设计和研制了一种汽车真空辅助制动系统,该系统主要包括机械执行机构、制动吸盘、真空系统、弹射收起系统、控制系统五个部分。对该系统进行了理论分析和实验研究,结果表明,该系统可显著提高汽车制动效能, 可有效缩短汽车紧急制动时的制动距离,从而有效降低交通事故的发生概率并降低交通事故的严重程度。     

核电汽轮机控制系统突发工况响应

汽轮机控制系统在突发工况下的响应关系到整个核电站的机组运行状态。本文通过对秦山核电二厂3、4号机组投运以来的汽轮机数次瞬态工况下的响应,比如:电网扰动、调频回路动作等工况为线索,对汽轮机控制系统的结构、功能、逻辑进行了说明。     

部分负荷工况下电控发动机空燃比控制研究

空燃比的精确控制是现代车用汽油机控制最为关键的技术,部分负荷工况是电控汽油发动机运行最多的工况,研究部分负荷工况下的电控发动机空燃比控制系统对降低排放提高燃油经济性具有重要意义。文中在进行了目标空燃比控制分析后,首先建立了发动机数学模型,设计了部分负荷工况下的空燃比PID控制系统和模糊PID控制系统,并建立了发动机空燃比控制的仿真模型,然后与未采取控制策略的常规控制系统的空燃比控制效果进行对比。仿真结果表明,在部分负荷工况下采用模糊PID算法的控制效果最好,控制精度较高、控制性能最优,PID算法次之。     

核压力容器缺陷验收确定性准则的失效概率分析

在含缺陷结构完整性评定中,即使满足确定性分析要求,结构也会存在发生失效的可能。提出确定性缺陷验收准则所对应失效概率的分析方法,以计算在满足确定性分析要求的临界条件下结构的失效概率。采用该方法可以验证确定性缺陷验收准则是否能够满足结构的概率要求,也可依据概率要求指导确定性缺陷验收准则中安全系数的制定。针对ASME BPVC第XI卷中基于应力强度因子的缺陷验收准则,以正常降温工况和承压热冲击事故工况为例,对一典型含缺陷反应堆压力容器(Reactor pressure vessel,RPV)进行确定性分析和概率分析,得到相应工况下的临界裂纹尺寸及失效概率,并讨论安全系数对含缺陷RPV失效概率的影响。所分析案例表明,ASME标准中规定的安全系数在正常降温工况下尚不能保证RPV临界失效概率低于核安全的概率要求。     

液压支架电液控制系统的研究与应用

针对目前部分国产液压支架电液控制系统的实际使用现状及存在的问题,调研了煤矿生产的实际工况环境,分析了控制系统的典型结构和工作原理,阐述了控制系统的性能特点,指出了电液控制系统需要解决的关键技术问题。为此类产品的研发提供了一定的参考。     

集装箱偏载工况下提升机构控制系统设计

以某型集装箱装卸搬运机的提升机构为研究对象,应用ADAMS软件创建了提升机构的钢丝绳模型,研究了提升机构在集装箱偏载工况下的提升规律,运用经典PID理论设计了提升机构控制系统。仿真结果表明,该控制系统能够有效改善偏载工况下集装箱在提升过程中的稳定性。     

基于视觉感知的半主动悬架控制系统研究

通过对目前半主动悬架控制系统的研究分析,传统的半主动悬架控制系统在经过一些特定的工况产生的瞬态冲击,可能会由于悬架控制系统的响应迟滞效应无法对每次较大的瞬态冲击做到快速控制响应,对于整车舒适性带来一定影响。本文提出一种基于深度学习图像检测技术的半主动悬架控制系统,旨在通过视觉感知前方对车辆乘坐舒适性带来较大影响的特征工况(如减速带),再融合半主动悬架特殊工况识别控制算法,优化半主动悬架控制系统。     

基于LabVIEW的工控机控制系统的开发及应用

介绍了一种以工业控制计算机与I／O板卡为硬件平台,软件LabVIEW为开发环境的工业控制系统的解决方案,并将该控制系统与单片机、PLC等控制系统进行了比较分析。采用该控制方案实现了核电用燃料棒上端塞压力电阻焊机的自动控制,实践表明,系统运行可靠、稳定,符合实际工况要求。     

近红外距离选通成像系统作用距离研究

近红外脉冲激光照明的距离选通成像技术能够有效降低后向散射的影响,提高夜间以及恶劣环境下光电成像系统的作用距离。针对近红外激光距离选通成像系统的设计需要,以系统输出信噪比大于该目标的形状和识别概率所对应的人眼阈值信噪比为原理。在微光成像系统作用距离公式的基础上。添加主动照明系统的影响因素,建立了近红外激光距离选通成像系统的作用距离模型。该模型得到的结果和实际系统实验结果相比具有很好的一致性,表明该模型合理,可靠。在近红外激光距离选通成像系统的设计过程中,可以用此模型对系统进行作用距离预测。     

Precise slave-side force control for security enhancement of bilateral motion control during application of excessive force by operator

The high probability of a future environment featuring human–robot coexistence is motivating studies on man–machine interface safety. Bilateral control that enables contact including haptic sensations to distant locations through master–slave actuators is an emerging technology in the fields of human tele support, care, and assistance. This paper proposes a safe operating technique for bilaterally controlled robots based on environmental properties. This technique protects the remote environment from excess force applied by the master operator. We have described the operation as the normal mode and safe mode. The system follows four-channel acceleration-based bilateral control throughout normal mode operation. The safe mode operation corresponds to virtual environmental sensation of the master operator together with force-position limitation on the slave side. In this work, a conventional virtual stiffness controller was modified to overcome the loss of environmental sensation from the remote slave side. Precise simultaneous force-position control is achieved on the slave side by focusing on the object safe force limit. The modified method is applied to the bilateral controller preserving the common mode force servoing property. The proposed method is validated using experiments.     

中速柴油机冷却系统恒温控制设计与研究

针对柴油机不同的工况对冷却水温度要求不同,原冷却系统不能随工况的变化自动调节温度,设计了柴油机智能冷却系统恒温控制系统。通过热平衡实验获得柴油机各工况最佳工作状态的冷却水温度和流量,利用单片机控制变频器水泵转速和电控三通旁通阀的开度对冷却水温度自动控制。实验结果表明:该系统可以随柴油机工况变化将冷却水温度恒定控制在最佳工作温度,达到了节油效果,最大节油率为5.4%,平均节油率为3.6%。     

功率超声系统负载的检测及模糊控制

功率超声医疗设备在治疗的过程中,为了取得良好的超声乳化效果,要求振动系统在不同的负载下都具有较大的输出振幅,这就要求振动系统在不同的负载下都工作在匹配状态下.文章首先分析了纵向复合棒大功率换能器加接变幅杆和刀具的振动系统的等效机电模型,然后根据等效机电模型分析了功率超声振动系统动态阻抗匹配的基本原理.同时针对功率超声系统的工作特点设计了一种动态负载在线检测方法,得到反映负载状态及其变化趋势的参数,并根据识别出的动态负载确定出模糊控制器的输入输出参数.最后给出了一种实用的模糊控制算法进行振动系统的动态阻抗匹配.实验结果表明,利用模糊控制器进行动态阻抗匹配能保证振动系统在变负载的情况下仍然获取较高的电功率和较好的超声乳化效果.     

Loss model based efficiency optimized control of brushless DC motor drive

Energy efficiency improvement of electrical motor drives has recently become a very interesting subject. Several methods have been proposed in the literature to improve the efficiency of permanent magnet synchronous machine (PMSM) with sinusoidal back-EMF. These methods are not precise and appropriate for brushless DC machine (BLDCM) with trapezoidal back-EMF. As a unique solution, this work introduces a flux controlled based loss minimization algorithm suitable for BLDCM that considers iron loss as well as influence of back-EMF harmonics; consequently promotes efficiency of machine. In this regard, the loss model of PMSM is extended based on multiple reference frame analysis to include back-EMF harmonics of BLDCM. As an advantage, proposed modified loss model does not require any additional data about the dimensions of machine that makes it suitable for industrial motor drive applications. The Proposed loss model is validated through experimental tests in different operating conditions. Afterward, by applying direct torque and indirect flux control of BLDCM as the control technique, d-axis current in the rotor reference frame is controlled to reduce the air gap flux and consequently iron loss of the machine. Finally, a procedure is presented to determine the optimum d-axis current which maximizes the efficiency. Effectiveness of proposed control system is evaluated using simulation results in MATLAB/Simulink and experimental results on a practical prototype. It is indicated that depending on the operating conditions, about 2% to 11% of efficiency improvement would be achieved in the proposed method.     

A novel composite adaptive flap controller design by a high-efficient modified differential evolution identification approach

The optimal tuning of adaptive flap controller can improve adaptive flap control performance on uncertain operating environments, but the optimization process is usually time-consuming and it is difficult to design proper optimal tuning strategy for the flap control system (FCS). To solve this problem, a novel adaptive flap controller is designed based on a high-efficient differential evolution (DE) identification technique and composite adaptive internal model control (CAIMC) strategy. The optimal tuning can be easily obtained by DE identified inverse of the FCS via CAIMC structure. To achieve fast tuning, a high-efficient modified adaptive DE algorithm is proposed with new mutant operator and varying range adaptive mechanism for the FCS identification. A tradeoff between optimized adaptive flap control and low computation cost is successfully achieved by proposed controller. Simulation results show the robustness of proposed method and its superiority to conventional adaptive IMC (AIMC) flap controller and the CAIMC flap controllers using other DE algorithms on various uncertain operating conditions. The high computation efficiency of proposed controller is also verified based on the computation time on those operating cases.     

基于LOGO技术的智能型混凝土搅拌主机控制器

本文阐述了混凝土搅拌主机的工作原理及其自动控制系统，提出了LOGO的编程技巧和解决实际生产问题的方法，尤其是对提高混凝土生产率，系统的故障诊断和生产过程的处理等方面做了切实可行的论述。     

高速列车牵引电机的同步虚拟主轴控制

针对高速列车牵引电机的同步控制问题,分析了系统同步性对于列车运行状态的影响作,并比较了不同控制策略的优势与不足,提出了利用虚拟主轴控制满足列车牵引系统高同步性的需求的方案,在Matlab中结合传统的虚拟主轴控制理论及列车牵引电机实际运行情况,对传统虚拟主轴控制模型控制参数做出调整,对启动阶段的控制策略进行了优化,建立了一个包含四台永磁牵引电机的同步控制系统模型。利用所建模型分析了系统发生负载扰动,负载不平衡等情况下转速,转矩,转速差,转角差的变化情况,并分析了系统保持同步的临界条件。研究结果表明,将虚拟主轴控制策略应用在高速列车牵引电机的同步控制之中,有着同步性高、响应迅速等的优点,该控制策略有着良好的应用前景。     

Torsional thrust balance measurement system development for testing reaction control thrusters

The paper describes the design, development, and testing of a torsional-type thrust stand to evaluate the performance of <40 N class cryogenic propellant reaction control thrusters. New thrust measurement techniques for cryogenic propellant fed reaction control systems at this thrust class are needed as current methods are deficient in providing reliable test data. The torsional thrust stand primarily consists of a balanced moment arm rotating around a set of frictionless pivots. The displacement of the moment arm due to applied thrust was tracked using a laser displacement sensor. A post-processing technique was developed to determine thrust values from displacement data. The measurement capability of the thrust measurement system is exemplified herein through the test firing a LOX/Methane thruster at steady-state and pulsing conditions. Effects of thruster mass and feed system stiffness on thrust-stand measurement characteristics were also assessed. The measurement system provided repeatable thrust data at steady-state and pulsing operating conditions.