Dynamic Simulation and Valve Structure Optimization of an Electro-Hydraulic Clutch Shift Control System in an Automatic Transmission

The electro-hydraulic clutch control system controls the transferred torque of gear-shifting clutches in clutch-to-clutch transmissions. A nonlinear dynamic model of an electro-hydraulic clutch shift control system is presented. The mechanical and fluid subsystems of all valves are investigated, including their interactions. Model validation of the electro-hydraulic valve system is performed by comparing the simulated and measured pressure curves. The dynamic characteristics of the electro-hydraulic clutch shift control system with different supply pressures and different fluid temperatures are simulated and evaluated. It is found that pipes which are often ignored between the electro-hydraulic valve system and the clutch piston,have strong influence on clutch piston chamber pressures. In order to satisfy the required time and reduce the fluctuation of the clutch piston chamber pressures,the orifices' diameters and valve structure are optimized.

An Active Inrush Current Limiter Based on SCR Phase Shift Control for EV Charging Systems

This article gives an overview of the main passive solutions and active techniques, based on AC switches to limit inrush currents in medium power AC-DC converters （up to 3.7 kW） for electric vehicle charging systems. In particular, a strategy, based on SCR （silicon controlled rectifier） phase, shift control in a mixed rectifier bridge with diodes and thyristors, is proposed. The challenge is to help designers optimize the triggering delay of SCRs to both limit the peak value of inrush current spikes and optimize the charge duration of the DC-link capacitor. A mathematical model （Mathcad engineering tool） has been defined to point out, the interest of a variable triggering delay to control SCRs to meet the expectations described previously. Experimental measurements using an industrial evaluation board of the AC-DC converter demonstrate the robustness of the method.

Iterative Learning Control for a Class of Linear Continuous-time Switched Systems with Fixed Initial Shifts

This paper deals with the problem of iterative learning control for a class of linear continuous-time switched systems in the presence of a fixed initial shift. Here, the considered switched systems are operated during a finite time interval repetitively. According to the characteristics of the systems, a PD-type learning scheme is proposed for such switched systems with arbitrary switching rules, and the corresponding output limiting trajectories under the action of the PD-type learning scheme are given. Based on the contraction mapping method, it is shown that this scheme can guarantee the outputs of the systems converge uniformly to the output limiting trajectories of the systems over the whole time interval. Furthermore, the initial rectifying strategies are applied to the systems for eliminating the effect of the fixed initial shift. When the learning scheme is applied to the systems, the outputs of the systems can converge to the desired reference trajectories over a pre-specified interval. Finally, simulation examples illustrate the effectiveness of the proposed method.

Shifting force control of an AMT heavy-duty truck based on manual shift test

Taking a heavy-duty truck as a research platform,the changing characteristics of shifting force,shift time,and slipping work are obtained through theoretical analysis and manual shift test of a real vehicle. Based on the analysis of the test results,a gear-shifting control strategy of the hydraulic automated shift control system is designed and experimentally verified on the bench. By optimizing the control parameters of high-speed switching valves,a control strategy and parameters are obtained,which can meet the requirements of dynamic performance and reliability.

Controlling the Goos-H?nchen Shift via Incoherent Pumping Field and Electron Tunneling in the Triple Coupled InGaAs/GaAs Quantum Dots

We study the controlling of the Goos-Hanchen （GH） shifts in reflected and transmitted light beams in the triple coupled InGaAs/GaAs quantum dot （QD） nanostructures with electron tunneling and incoherent pumping field. It is shown that the lateral shift can become either large negative or large positive, which can be controlled by the electron tunneling and the rate of incoherent pump field in different incident angles. It is also demonstrated that the properties of the OH shifts are strongly dependent on the probe absorption beam of the intracavity medium due to the switching from superluminal light propagation to subluminal behavior or vice versa. Our suggested system can be considered as a new theoretical method for developing a new nano-optoelectronic sensor.

Shift scheduling strategy development for parallel hybrid construction vehicles

The shift scheduling system of the transmission has an important effect on the dynamic and economic performance of hybrid vehicles. In this work, shift scheduling strategies are developed for parallel hybrid construction vehicles. The effect of power distribution and direction on shift characteristics of the parallel hybrid vehicle with operating loads is evaluated, which must be considered for optimal shift control. A power distribution factor is defined to accurately describe the power distribution and direction in various parallel hybrid systems. This paper proposes a Levenberg-Marquardt algorithm optimized neural network shift scheduling strategy. The methodology contains two objective functions, it is a dynamic combination of a dynamic shift schedule for optimal vehicle acceleration, and an energy-efficient shift schedule for optimal powertrain efficiency. The study is performed on a test bench under typical operating conditions of a wheel loader. The experimental results show that the proposed strategies offer effective and competitive shift performance.

Analysis of a novel phase-shifted soft switch converter

In this paper, on the basis of the phase shifted controlled zero voltage switch (ZVS) full bridge converter with pulse width modulation (PWM), a novel zero voltage and zero current switch (ZVZCS) PWM converter using a simple auxiliary circuit was designed. The ZVZCS soft switch is achieved by the resonance among the resisting electromagnetic deflection capacitor, the capacitor of the simple auxiliary network and the leakage inductor of transformer. There are no dissipation devices of the saturation inductor and the auxiliary switch in the converter, meantime the capacitor of the auxiliary circuit is also used to clamp the voltage of the rectifier, and there is no additional clamped circuit. There is no big circulating current in the converter, all the active and passive devices work on the condition of the low current and voltage stress, and the proposed converter has wide load range and small duty loss.

Conformal Analysis of Spatial Shift in High Resolution Satellite Data (HRSD)

Advent of High Resolution Satellite Data (HRSD) with development of high spatial resolution sensors have revolutionized the generation of large scale maps. Generation of large scale digital utility maps using HRSD involves different methodologies and includes several steps wherein errors or spatial shift may be induced at any stage of data generation. It may be interesting to note that the characteristics of the spatial shift vary with methodologies adopted in its processing and has unique implications with respect to the data usage along with its application. Spatial shifts of points on a satellite data is result of unexpected translation and rotation of pixel with respect to the original location. Present study analyzes the spatial shift generated in satellite data with reference to the change in area and orientation of a group of pixels i.e. conformal and equal area properties of the rectified satellite data. This study aims to establish a relationship between the spatial resolutions of the satellite image used for digital map generation with the spatial accuracy achieved. In this study, Ground Control Points (GCP’s) identified on satellite data for a sample study area were validated using Differential Global Positioning System. Five different high resolution satellite images were analyzed to verify changes in area and shape with reference to the GCP’s. The results indicate that with improvement in the spatial resolution, higher precision in the digital maps is accomplished in terms of spatial shift of the points.

基于VeriStand的硬件在环仿真系统在LF 2204动力换挡拖拉机上的应用

考虑到新的测试软件被开发后,拖拉机实车测试的安全性,有效性和高经济性等多方面因素的影响,提出了一种基于NI-VeriStand的HIL(硬件在环仿真系统)在LF 2204动力换挡拖拉机控制系统上的应用,基于仿真软件SimulationX对动力换挡拖拉机设计整车仿真模型,通过该模型应用HIL仿真系统对动力换挡控制系统策略软件进行全面的功能测试,以确定该控制系统的可靠性、完整性。

基于Modbus/TCP协议的ATS与FSK系统间通信接口设计

根据墨西哥某城市地铁指挥控制系统的设计需求,列车自动监控(ATS)系统与频移键控(FSK)系统之间数据交互采用网络接口,基于Modbus/TCP协议实现相应的以太网通信。为此提出基于Modbus/TCP协议的ATS与FSK系统间通信接口设计方案:利用Modbus/TCP协议的扩展灵活性,在传统Modbus/TCP协议的基础上进行扩展,实现ATS与FSK系统间的模拟列控信息、列车检测信息、FSK传输配置信息、网络配置信息的安全可靠传输;为了高效便捷地将从网口接收的信息解析后传输给FSK系统,选择在ARM/Linux+FPGA平台上实现通信接口。测试验证结果表明:该通信接口设计方案结构清晰且方便移植,能够正确有效地实现ATS与FSK系统间通信。

基于动力系统协调控制的AMT换挡品质研究

配备AMT机械式自动变速器的车辆在换挡时变速器的速比会突然发生变化,致使发动机输出轴和变速器输出轴之间产生转速差、车辆出现冲击、离合器产生过度磨损等情况。基于此,提出了换挡过程中精确控制发动机转速和转矩的反馈控制、时间最优控制和PID控制相结合的协调控制算法,以及利用电机的辅助作用,快速补充换挡过程中的动力中断,提高了换挡品质。建立综合考虑发动机、电动机、离合器和电子节气门相互协调控制的换挡控制策略。通过仿真试验,表明该控制策略能有效地提高换挡品质。

重型卡车变速器控制系统的设计及实验分析

为进一步减少重型卡车司机在驾驶过程中的工作量,降低重型卡车汽车的油耗,提出了采用传递效率更高、寿命更长以及结构更简单的电控系统替换传统的机械式变速器,在对重型卡车变速器简单概述的基础上,完成了变速器电控系统的硬件和换挡流程的设计;最后,通过构建实验平台对重型卡车变速器电控系统的换挡性能进行验证,得到了理想的控制效果。

改进移相控制下PMSG-PET系统回流功率的优化

针对电力电子变压器作为风电系统并网接口系统存在回流功率的问题,通过优化电力电子变压器的控制方法,改进传统的双重移相控制方法,在传统双重移相控制的基础上,改变移相比D1、D2,使二者的组合达到最优,能够降低系统中的回流功率,提高系统效率,在Matlab中对改进控制方法后的系统进行建模与仿真。结果表明,改进前输出功率最小值大约为-5 kW,将改进后的移相控制方法应用到PMSG-PET系统中,改进后输出功率最小值大约为-1.5 kW。该控制方法能够有效降低系统回流功率,证明了改进移相控制方法的有效性。

基于模型预测控制的输入并联输出串联双有源桥变换器均压控制策略

以双有源桥变换器(dual-active-bridge converters, DAB)为子模块、输入端并联输出端串联(input parallel output series, IPOS)构成的IPOS-DAB变换器是全直流风电系统实现风电直流汇集与送出的关键枢纽。IPOS-DAB变换器在工程实际应用中元器件参数存在差异,并串联时不同DAB子模块输出功率不均衡,导致DAB子模块输出电压电流不均衡,进而会造成子模块损坏的机率大增,极大地降低了系统的可靠性。传统均压控制存在可靠性较低、动态性能不足的问题,因此无法满足外部动态扰动时的控制要求。针对此问题,结合模型预测控制(model predictive control, MPC)方法的优势,采用模型预测控制对IPOS-DAB变换器进行均压控制。首先根据IPOS-DAB变换器建立预测模型,然后设计控制目标函数及整体控制策略。最后在Matlab/Simulink中搭建系统模型,在不同工况下与传统均压控制进行对比仿真验证,证明了所提控制策略具有更好的均压控制效果。

基于模糊算法的MCR-CPT移相控制策略研究

为提高磁耦合谐振式非接触电能传输(MCR-CPT)系统的电能传输质量,针对PID控制器在系统工况发生变化时适应性较差、无法及时更新和抗干扰能力弱的问题,提出一种适用于移相全桥CPT系统双闭环双输入模糊PID控制策略,并在此基础上以电压环为例,改进成三输入模糊PID控制策略,利用模糊控制分析工况变化,在线整定PID控制器的相关参数,从而稳定系统输出。仿真与实验证明了基于模糊PID算法的MCR-CPT移相控制策略具有良好的鲁棒性与抗干扰能力。

Closed-Loop Iterative Learning Control for Discrete Singular Systems with Fixed Initial Shift

This paper deals with the problem of iterative learning control for a class of discrete singular systems with fixed initial shift. According to the characteristics of the discrete singular systems, a closed-loop learning algorithm is proposed and the corresponding state limiting trajectory is presented.It is shown that the algorithm can guarantee that the system state converges uniformly to the state limiting trajectory on the whole time interval. Then the initial rectifying strategy is introduced to the discrete singular systems for eliminating the effect of the fixed initial shift. Under the action of the initial rectifying strategy, the system state can converge to the desired state trajectory within the pre-specified finite time interval no matter what value the fixed initial shift takes. Finally, a numerical example is given to illustrate the effectiveness of the proposed approach.

高效机械排挡系统在新能源汽车中的应用与优化探索

为了提升驾驶体验,进行高效机械排挡系统在新能源汽车中的应用与优化探索。通过对机械排挡系统的结构和材料进行优化设计,实现车辆的轻量化,提高车辆的性能和经济性。引入智能化控制系统实现车辆与机械排挡系统的智能互联,根据车辆行驶状态快速、准确地换挡,提高驾驶舒适度和车辆的行驶效率。控制噪声和振动,以提供更舒适的驾驶体验。实验结果表明,高效机械排挡系统可以平稳地实现新能源汽车中高低挡的转换,具有应用价值。

结合主导特征值法的变结构控制及其应用

本文结合主导特征值位移法和变结构控制理论，提出了一种新的基于部分状态反馈量的变结构控制系统设计方法，并依据这种方法设计了统一潮流控制器（ＵＰＦＣ）的控制系统。仿真结果验证了其有效性。

AMT混合动力系统驱动模式能量优化控制

在AMT混合动力系统转矩优化分配算法的基础上,提出了以动力总成系统效率最大化为目标的AMT档位优化控制来优化转速,并通过离线优化求解确定了不同状态(发动机和电机功率、车速、蓄电池SOC)下AMT的最优化档位控制规律和电机最优化转矩。仿真试验结果表明,能量优化控制算法显著改善了整车燃油经济性。

越野车辆的自动变速系统

基于CAN总线通信,利用机、电、液、气一体化控制技术,为一种越野车辆研制了机械自动变速系统.根据车辆传动系统的特点,设计了自动变速操纵机构、系统控制电路和控制软件,自动变速操纵机构的设计保留了车辆应急状态下的人工干预功能,电控系统的设计实现了系统与其它车载系统的车辆信息共享,在优化车辆整体性能的同时,进一步降低了系统的成本,并实现了动力传动一体化控制.实车试验结果表明,系统的各项设计达到了实际运用的要求.