汽车防盗油阀密码控制器的研究

针对汽车防盗,该文开发了一种密码控制的油路阀防盗系统,油路控制阀安装在汽车点火器处,密码控制器则安装在驾驶室内的操作台上.利用该控制系统,任何人进入车辆后,都必须输入正确的密码才能打开安装在油泵与汽车点火系统之间的油路控制阀,接通油路后,才能启动汽车发动机.在密码控制器中,设计了报警模块,当输入密码错误超过规定的次数后,控制器启动报警系统并同时锁定键盘.为了避免汽车意外熄火油路阀关闭切断油路以及密码控制器掉电而需要重新输入密码的麻烦,控制器的存储单元能记忆步进电机的当前位置并保持阀芯的当前开口,便于驾驶员快速重启发动机.最后利用摩托车发动机进行了实验研究,实验结果表明该密码控制油路阀系统具有很好的防盗作用.     

磁流变阻尼器实验建模及模糊半主动振动控制

利用磁流变阻尼器特性试验数据,通过曲线拟合等手段建立了双sigmoid力学模型。该模型的参数是控制电流和振动频率、振幅的函数,能准确描述不同激励条件下阻尼力-速度滞回特性。建立了双层隔振系统模型,分析了阻尼比对传递函数的影响。提出了一种模糊半主动振动控制算法。仿真结果表明,该控制算法在宽频范围上能取得很好的隔振效果。     

压电式空气补气阀技术研究及应用

介绍了一种基于压电双晶片的空气补气阀(ACV)。该压电阀安装于摩托车化油器怠速补气通道,通过现场传感器信号的采集,根据控制策略,利用压电阀的流量特性,实施脉冲宽度调制(PWM)驱动控制,达到国Ⅲ排放要求。该文通过对逆向压电效应、压电方程的理论分析,依据实际的双晶片尺寸,得出空气补气阀的实际位移和力矩,并通过实际的测试,发现在100V、15Hz的PWM控制波形驱动下,该压电补气阀呈现出了良好的稳定性和一致性,满足了电控化油器中对怠速智能补气的需求。     

高压静止无功补偿器用晶闸管阀均压／阻尼电路参数的优化

静目无功补偿器（SVC）在提高电力系统供电质量和运行稳定性等方面发挥，重要作用。本文详细分析TSVC用晶闸管阀的均压／阻尼电路参数对系统电压和电流的影响，通过仿真计算，分析提出了优化品闸管阀均压／阻尼电路参数的指导原则。试验比较结果表明：采用优化电路参数，关断时刻晶闸管阀产生的电压冲击小、无电压振荡，对系统的影响小。     

模糊逻辑算法在SVC控制中的应用浅析

针对电力系统中SVC装置的应用特点,提出了一种将模糊逻辑算法应用到SVC控制算法中,然后通过实验对比三种控制算法,从而得出了一种模糊逻辑算法与PI算法相结合的新型改进算法。该算法初步解决了SVC装置补偿过程中在某些系统工况下出现改善电压质量与提高功率因数相矛盾的问题。     

特高压直流系统旁路开关运行风险分析及预控措施研究

文章指出旁路开关位置检测功能存在的隐患,提出相应的解决办法。文章结合普侨直流系统旁路开关故障实例,指出阀组解锁过程中旁路开关分位信号延误导致双阀组跳闸的风险,研究避免对侧旁路开关保护误跳的技术措施,并通过仿真试验验证其效果。     

基于半马尔科夫决策过程的视频传输拥塞控制算法

针对传输控制协议(TCP, transmission control protocol)的拥塞控制算法未能满足视频传输质量要求的问题,提出了一种基于半马尔科夫决策过程的视频传输拥塞控制算法。首先, 为克服目前基于峰值信噪比的视频质量评估方法实时性低的缺点,设计了一种可在线运行的无参考视频质量评估方法。其次,根据接收端视频质量的反馈,采用半马尔科夫决策过程对拥塞控制进行建模,并通过求解此模型得到拥塞控制参数的调整策略。仿真实验结果表明,与目前典型的拥塞控制算法相比,该算法不但具备更好的TCP友好性,而且有效地提高了解码后视频序列的主观和客观质量。     

FFT在大型风电机组自适应控制中的应用

在大型风电机组传动系统降载控制策略中的滤波和加阻等方法均需要机组传动链扭振频率,而实际机组运行过程中的扭振频率难以精确获取。文中通过FFT实时分析发电机转速,提出通过计算能量密度自动判断振动的方法,实时监测风机扭振并计算振动频率。将计算结果作为风电机组自适应控制滤波和加阻的依据,使用该方法对实际的运行数据进行计算,计算结果验证了该方法能有效的监测风机扭振并计算出振动频率。     

微波组件振动过程失效分析及对策

电子产品的失效与其所承受的外界应力紧密相关,通过采取设计及工艺改进措施,降低薄弱部位承受的外界应力影响,提高产品的可靠性。通过对某型微波组件在振动试验过程中焊点出现开裂的案例分析,提出了采用镀银铜线软连接、安装孔倒角处理和增加点胶固定等措施,并经量级分别为12g、15g、22.3g(g=10m/s2)的随机振动及正弦扫频振动、温度冲击等试验验证,满足了微波组件在整机上的使用需求,防止在振动中因焊点开裂造成产品失效。     

羽于公交车辆的电子动力传动系统将揭开面纱

Adura系统已经在公交汽车和多功能汽车的传动系统中秘密工作了两年，其使得这些车辆的燃料系统更经济，排放等级也得以提高。这种系统是由加州一家公司开发的，包含了高度模块化的系统电子部件，一个智能控制软件平台，以及首个工业用现场安装能量储存系统。该储存装置可根据25、50或100英里初始行程配置在纯电子模块中，进而进行后续的混合工作。     

以太网与无线WIFI传输的机车车辆检测系统

为了解决传统车辆检测装置安装布线复杂,传输速率慢的缺点,设计了一种无线网络化的车辆检测系统。该系统以STM32为核心建立主控制器,MSP430单片机为核心建立无线传感器网络节点,通过传感器完成多种车辆振动信号的采集。采用无线WIFI与以太网两种通信方式实现控制指令与采集数据的高速传输,同时设计了基于C#.NET平台设计的人机交互界面,实现对车辆运行状态的实时监测。通过实验验证,系统能够完成车辆运行过程中速度,加速度等振动信号的高速采集、传输与处理。     

Performance based systematic design methodology for development and flight testing of fuel engine powered quadrotor Unmanned Aerial System for industrial applications

This paper presents a systematic study of the design optimization, development, vibration analysis and flight testing of a single power plant variable pitch quadrotor Unmanned Aerial System (UAS) for industrial applications. The use of variable pitch rotors enables the use of a two-stroke internal combustion engine for powering the four rotors through a mechanical transmission. The proposed methodology is described by carrying out the design of a quadrotor UAS with 2–3 kg payload capacity and have endurance in excess of one hour. The study is conducted in a systematic manner. First, the design of rotors is optimized for minimum power consumption during hover as well as forward flight condition using physics based simulation developed and validated for this purpose. From the rotor optimization, an untwisted rotor blade with taper ratio of 0.6 and aspect ratio of 10 appeared to be an optimal choice for the current design. Next, the powerplant selection is carried out based on the optimized rotor designed earlier. Next, two different approaches for mechanical power transmission design is considered: torque tube-bevel gear and belt–pulley system based designs. The transmission system designed using belt and pulley was nearly 14% lighter and showed greater tolerance to manufacturing imperfections. Next, two prototypes are designed and its static and dynamic analysis is carried out to ensure its airworthiness. A Proportional Integral Derivative (PID) based attitude controller is developed using quarternions for attitude stabilization and trajectory tracking to test the flight in simulation and then subsequently on the actual vehicle by implementing it on PixHawk autopilot board. Finally, system integration is carried out to build two prototypes of engine powered quadrotor UAS. Then, vibration data is recorded using the sensors onboard to conduct the vibration analysis and design an efficient vibration isolator. Performance analysis is also, carried out to estimate the speed for best endurance (11 m/s) and best range (27 m/s) for the variable pitch quadrotor designed. The estimated best endurance achieved is 2.2 h and estimated best range is more than 150 km. This design revisits and solves the challenge of developing an agile helicopter without cyclic pitch control which was first explored nearly a century ago.     

高压隔膜泵运行状态远程监测系统的设计

高压隔膜泵是矿浆管道输送系统的动力源,随着无人值守泵站的投入运行,如何远程监测高压隔膜泵的运行状态就成为亟需解决的问题。文中设计了一种基于STM32的高压隔膜泵运行状态远程监测系统。该系统实时采集单向阀振动信号,将采集到的振动信号数据通过以太网传输到远程服务器中,在服务器中采用固有时间尺度分解方法(ITD),对高压隔膜泵单向阀振动信号进行分析,从而实现对高压隔膜泵运行状态的远程监测。实验结果表明,该系统采集信息准确,传输速度快速且稳定,可以在工业行业推广使用。     

高速列车司机室异常噪声分析与控制研究

对高速列车司机室内的噪声和振动进行了测试,分析车内的噪声与振动水平、噪声传递路径及声源特性,探寻造成司机室噪声水平过大的原因,提出通过车轮鏇修解决司机室噪声过大问题的建议,并对车轮鏇修前后的司机室噪声与振动水平进行了对比测试分析,并由此开展了高速列车司机室噪声控制措施的研究.结果表明,车轮第20阶多边形是使车内噪声和振动过大,并形成588 Hz显著频率的主要原因.车辆结构在580 Hz附近存在局部模态区,当外界激振频率落在这一区域时,会激发车辆结构的共振.通过车轮鏇修,改善车轮多边形,可以在一定程度上缓解车内噪声问题.但是,优化车辆结构,使车辆模态避开车内噪声显著频率范围,才能从根本上解决包括司机室噪声过大在内的一系列由于共振引发的车内噪声问题.另外,结构振动声辐射对司机室显著声源具有一定贡献,针对司机室噪声控制,还需要采取一定的减振措施.     

Location prediction algorithm for a nonlinear vehicular movement in VANET using extended Kalman filter

Vehicular ad-hoc network (VANET) is an essential component of the intelligent transportation system, that facilitates the road transportation by giving a prior alert on traffic condition, collision detection warning, automatic parking and cruise control using vehicle to vehicle (V2V) and vehicle to roadside unit (V2R) communication. The accuracy of location prediction of the vehicle is a prime concern in VANET which enhances the application performance such as automatic parking, cooperative driving, routing etc. to give some examples. Generally, in a developed country, vehicle speed varies between 0 and 60 km/h in a city due to traffic rules, driving skills and traffic density. Likewise, the movement of the vehicle with steady speed is highly impractical. Subsequently, the relationship between time and speed to reach the destination is nonlinear. With reference to the previous work on location prediction in VANET, nonlinear movement of the vehicle was not considered. Thus, a location prediction algorithm should be designed by considering nonlinear movement. This paper proposes a location prediction algorithm for a nonlinear vehicular movement using extended Kalman filter (EKF). EKF is more appropriate contrasted with the Kalman filter (KF), as it is designed to work with the nonlinear system. The proposed prediction algorithm performance is measured with the real and model based mobility traces for the city and highway scenarios. Also, EKF based prediction performance is compared with KF based prediction on average Euclidean distance error (AEDE), distance error (DE), root mean square error (RMSE) and velocity error (VE).     

The design of low cost valve-and-pump compounded pressure control system for the hydro viscous clutch

Hydro viscous clutch (HVC) is a power transmission unit which relies on shear stress of fluid to transmit driving torque. The conventional pressure control system suffers from high minimum operating pressure problem. This makes the HVC has a large drag torque and greatly limits the usage flexibility. In this article, a valve-and-pump compounded pressure control (VCPC) system is proposed for the hydro viscous clutch (HVC) to enlarge the working pressure range in the low pressure direction. The pressure of the control cylinder is adjusted by the rotary speed of pump or the electro-proportional relief valve (ERV) when the VCPC system works on different pressure stage. The adaptive robust control (ARC) algorithm and the feedforward PID algorithm are introduced into the VCPC system for the purpose of obtaining better pressure tracking performance. The effectiveness of the proposed VCPC system is validated through the compared experiments. Electromagnetic interference is considered and experiment results are carefully analyzed. It can be concluded that the pressure control range is increased by 38% with the proposed VCPC system. And compared with conventional control algorithms, the ARC algorithm has a better pressure tracking performance and relatively smooth input signal on low pressure stage.     

Self-powered In-Phase Sensing and Regulating Mechanical System Enabled by Nanogenerator and Electrorheological Fluid

Mechanical system with adjustable stiffness and damping (ASAD) shows great potential in vibration suppression of aircraft, vehicle, precise instrument, etc. However, current ASAD systems consist of power, sensing, and controlling components, which bring huge challenges of system reliability and integrability, and critically limit its application diversity. Herein, we proposed the first strategy for regulating ASAD system that is system simplification, self-powered and no-delay by deeply coupling triboelectric nanogenerator (TENG) and electrorheological fluid (ERF). Under the time-varying mechanical triggering, the local and time correlated output of TENG instantaneously applied on the ERF regulates the entire mechanical system dynamically and “in-phase”. As an illustration, the resonance of a cantilever system is effectively suppressed naturally without complicated controlling strategy, and the vibration isolating efficiency reaches up to 85.2%. Finally, a mechanical transmission system is demonstrated utilizing a rotary TENG and ERF, excellent soft-start performance is enabled by this self-regulating ASAD strategy. This work may provide the opening arsenal of methodologies used in self-powered and self-regulating mechanical systems.     

Cooperative and Opportunistic Channel Access for Vehicle to Roadside (V2R) Communications

This paper focuses on vehicle to roadside (V2R) communications in vehicular networks based on the IEEE 802.11 DCF MAC protocol. In vehicular networks, roadside units (RSUs) are typically spaced apart along the road and each vehicle can be connected to an RSU only when the vehicle is within its transmission range. Due to the high relative speed between a moving vehicle and a stationary RSU, the residence time of the vehicle within the coverage of each RSU is very short. Thus it is hard for the system to reach a steady state. With multi-hop forwarding, in which a vehicle may be connected to an RSU through relaying over other vehicles, the connection time of each V2R access may be extended. But this is at the expense of introducing wireless interference among vehicles, which may dramatically degrade the system performance. To tackle these challenges, we propose a new mechanism called Proxy-based Vehicle to RSU access (PVR) for V2R communications. This protocol is designed to exploit cooperative and opportunistic forwarding between any two distant RSUs and to emulate back-to-back transmissions within the coverage of an RSU. As a result, it can shorten the access delay by taking advantage of opportunistic forwarding and mitigate the interference problem during the short residence time within the coverage of an RSU. The simulation results show that PVR achieves excellent performance and outperforms all existing solutions for V2R communications in vehicular networks.     

DSP-Based Sensorless Electric Motor Fault Diagnosis Tools for Electric and Hybrid Electric Vehicle Powertrain Applications

The integrity of electric motors in work and passenger vehicles can best be maintained by frequently monitoring its condition. In this paper, a signal processing-based motor fault diagnosis scheme is presented in detail. The practicability and reliability of the proposed algorithm are tested on rotor asymmetry detection at zero speed, i.e., at startup and idle modes in the case of a vehicle. Regular rotor asymmetry tests are done when the motor is running at a certain speed under load with stationary current signal assumption. It is quite challenging to obtain these regular test conditions for long-enough periods of time during daily vehicle operations. In addition, automobile vibrations cause nonuniform air-gap motor operation, which directly affects the inductances of electric motors and results in a noisy current spectrum. Therefore, it is challenging to apply conventional rotor fault-detection methods while examining the condition of electric motors as part of the hybrid electric vehicle (HEV) powertrain. The proposed method overcomes the aforementioned problems by simply testing the rotor asymmetry at zero speed. This test can be achieved at startup or repeated during idle modes where the speed of the vehicle is zero. The proposed method can be implemented at no cost using the readily available electric motor inverter sensors and microprocessing unit. Induction motor fault signatures are experimentally tested online by employing the drive-embedded master processor (TMS320F2812 DSP) to prove the effectiveness of the proposed method.      

Robust speed control system considering vibration suppressioncaused by angular transmission error of planetary gear

This paper proposes a new robust speed control to suppress vibration caused by angular transmission error of planetary gears. For this purpose, this paper first constructs a new numerical simulation model of angular transmission error of planetary gear, which is confirmed by experimental data from a robot arm. Next, in order to suppress the vibration caused by angular transmission error, we propose a robust speed control system based on disturbance observer and coprime factorization. Numerical simulation results show that the proposed system regulates the angular speed of motor satisfactorily, and it suppresses the vibration caused by angular transmission error