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所属行业:汽车制造业

  • 51731.2014年2季度汽车行业政策环境综述

    [汽车制造业] [2014-07-30]

    2014年2季度,汽车行业政策变化主要有两个方面:首先,为促进大气污染防治,工信部定于2014年底废止国三柴油车产品公告,自2015年起国三柴油车产品将不得销售。同时,国务院在车用成品油配套升级方面也做出了进一步的部署,我国柴油车国三时代宣告结束,国四大幕正式拉开。第二,工信部发布《轮胎行业准入条件》(征求意见稿),从企业布局和规模要求、工艺、质量和装备、能源和资源消耗、环境保护、安全生产和职业卫生、公告管理等多个方面提出了准入要求。准入门槛的设定将加快推动轮胎行业结构调整,规范生产经营秩序,抑制低水平重复建设,引导行业持续健康发展。
    关键词:汽车行业;环境综述
  • 51732.TSAFE接口控制文档V2.0

    [汽车制造业] [2014-07-30]

    This document specifies the data interface for TSAFE, the Tactical Separation-Assured Flight Environment. TSAFE is a research prototype of a software application program for alerting air traffic controllers to imminent conflicts in enroute airspace. It is intended for Air Route Traffic Control Centers ('Centers') in the U.S. National Airspace System. It predicts trajectories for approximately 3 minutes into the future, searches for conflicts, and sends data about predicted conflicts to the client, which uses the data to alert an air traffic controller of conflicts. TSAFE itself does not provide a graphical user interface.
    关键词:控制器;TSAFE接口;控制文档
  • 51733.并联型有源电力滤波器

    [汽车制造业] [2014-07-30]

    Shunt active power filters have been introduced as a way to overcome the power quality problems caused by nonlinear and reactive loads [9, 14, 23]. These power electronics devices are designed with the goal of obtaining a power factor close to 1 and achieving current harmonics and reactive power compensation [5, 6, 15]. The usual approaches [5, 15] for the control of shunt active filters are based on two hierarchical control loops: an inner one that assures the desired current and an outer one in charge of determining its required shape and the appropriate power balance as well. The control structure followed in this Chapter is the one in [7], in which the current controller is composed of a feedforward action that provides very fast transient response, and also of a feedback loop which includes an odd-harmonic repetitive control that yields closed-loop stability and a very good harmonic correction performance. In turn, the outer control law is based on the appropriated computation of the amplitude of the sinusoidal current network and, aiming at a robustness improvement, this is combined with a feedback control law including an analytically tuned PI controller. However, although the control system performance is very good, it shows a dramatic performance decay when the network frequency value is not accurately known or changes in time. For a better assessment of this issue this Chapter shows the experimental behaviors under constant and varying network frequency. This performance degradation is also presented and analyzed in terms of the THD, PF and cosφ. The Chapter organization is as follows. Section 7.1 introduces the plant, the control objectives and the two hierarchical control loops. Section 7.2 shows the odd harmonic controller designed for constant network frequency, also analysing the performance degradation through the THD, PF and cosφ. Section 7.3 details the results for the varying sampling time repetitive controller including the stability analysis by means of robust control theory. It is worth to say that the stability analysis using the LMI approach introduced in Section 3.3 can not be applied in this implementation since the size of the resulting matrices makes the problem computationally unsolvable. Section 7.4 and Section 7.5 present the implementation of the adaptive pre-compensation scheme and the robust design respectively and, finally, a second order HORC is applied in Section 7.6.
    关键词:控制器;并联有源;电力滤波器
  • 51734.汽车竞争情报-第509期

    [汽车制造业] [2014-07-30]

    报告从行业事件分析、市场环境、政策环境、分类环境、区域环境、国内对手情报、国外对手动向以及相关行业数据方面对汽车行业进行了分析评论。
    关键词:汽车;战略性分析;竞争环境;竞争对手;行业数据
  • 51735.基于干扰观测器的电动伺服加载系统的研究

    [汽车制造业] [2014-07-30]

    A novel double-loop control approach for reducing excess torque of the servo loading system based on disturbance observer is proposed.The mathematical model of the loading system is established by mechanism theory and the reasons causing the excess torque are analyzed,the nominal model and disturbance weighting function are determined based on an approximate method.Disturbance observer based the inner loop controller is designed by H∞ mixed sensitivity method and the external-loop controller is designed as the classical PID controller.Both the simulation and experiments results show that disturbance observer is feasible and effective to eliminate the excess torque,accuracy of the loading system is improved.
    关键词:控制器;干扰观测器;电动伺服加载系统
  • 51736.嵌入到FPGA的软核的模糊逻辑控制器的设计方法

    [汽车制造业] [2014-07-30]

    In this paper, the methodology for the design of fuzzy controllers for softcore processors, such as the Xilinx Microblaze embedded in the VIRTEX5 FPGA, is proposed to regulate the angular position of the axes of an experimental platform. The platform uses servomotors to control the rotational movements of the X-Y-Z axes, this with respect to the earth horizon. The angular position is feedback using three inclinometers sensors based on MEMS technology with SPI interface. The desired position is regulated using three independent fuzzy PD+I controllers, which use the error and change of error as input signals. The proposed methodology consists in the design and evaluation of the fuzzy controllers using the Fuzzy Logic Toolbox of Matlab.
    关键词:控制器;FPGA;软核;模糊逻辑控制器
  • 51737.无刷直流电机(BLDC)的可变电压轨控制

    [汽车制造业] [2014-07-30]

    A brushless DC (BLDC) motor achieves higher energy efficiency and endures less wear and tear than a traditional brushed DC motor due to the lack of friction between current coils and motor brushes; it requires additional control logic, however, often implemented using a microcontroller, to perform motor commutation. Standard drive circuitry consists of a rail voltage applied to a three-phase inverter and a pulse width modulated (PWM) signal applied to MOSFET gates in accordance with the commutation pattern. Typically, motor speed control is achieved by varying the pulse width applied to the gates while maintaining a fixed rail voltage. We implemented a proportional-integral (PI) feedback system to control motor speed while varying rail voltage. Using this PI controller, we examined the relationship between steady-state power consumption and rail voltage for a fixed reference, as well as the effect of variable rail voltage on transient controller response and total transient power consumption.
    关键词:控制器;无刷直流电机;可变电压轨
  • 51738.调制波形周期的归一化的单极性SPWM控制器

    [汽车制造业] [2014-07-30]

    The thesis mainly proposed a novel design method for Sinusoidal Pulse Width Modulation (SPWM) controller based on modulation waveform cycle normalization.T is the period ofsinusoidal modulation waveform,and T/n is the cycle of triangular carrier.Shift registers and adders of SPWM controller were designed to translate the 2n numerical value for SPWM waveform on-off switching points,which were calculated offline,to control the level of the outpout SPWM waveform,which is the key point of modulation waveform cycle normalization.In the thesis RTL function simulation verification by ModelSim and testing for FPGA have been achieved successfully.The results show that the novel SPWM controller is reliable,which has practical significance.
    关键词:控制器;调制波形周期;归一化;SPWM控制器
  • 51739.自适应控制器的适应时间和对驾驶的可用控制权影响

    [汽车制造业] [2014-07-29]

    Adaptive control is considered for highly uncertain, and potentially unpredictable, flight dynamics characteristic of adverse conditions. This experiment looked at how adaptive controller adaptation time to recover nominal aircraft dynamics affects pilots and how pilots want information about available control authority transmitted. Results indicate that an adaptive controller that takes three seconds to adapt helped pilots when looking at lateral and longitudinal errors. The controllability ratings improved with the adaptive controller, again the most for the three seconds adaptation time while workload decreased with the adaptive controller. The effects of the displays showing the percentage amount of available safe flight envelope used in the maneuver were dominated by the adaptation time. With the displays, the altitude error increased, controllability slightly decreased, and mental demand increased. Therefore, the displays did require some of the subjects resources but these negatives may be outweighed by pilots having more situation awareness of their aircraft.
    关键词:控制器;自适应控制器;试用时间;可用控制权;驾驶
  • 51740.气动定位阶段基于相对位置和相对加速度的的PDD~2控制器刚度和阻尼环的修改

    [汽车制造业] [2014-07-29]

    In our preceding works, the stage jerk feedback (SJFB) and base plate jerk feedback (BPJFB) schemes were successfully applied in a pneumatically actuated positioning stage. Where the relative position-based PDD~2 controller was used as the outer loop controller to maintain the positioning stability. However, since two accelerometers are used, each on the stage for SJFB and on the base plate for the BPJFB scheme, there is a possibility of modifying the stiffness and damping loops of PDD~2 controller from relative position-based to the relative acceleration-based inputs. Although there is no any advantage from the industrial application point of view, the bitterness of the modified PDD~2 controller is its simple structure while simple control scheme is desired. Therefore, this paper proposes the modification of stiffness and damping loops of PDD~2 controller such that to be energized by the relative acceleration signal. The objective is to check the feasibility of the proposed PDD~2 controller for the positioning performance without and with both SJFB and BPJFB schemes. It will help us in the future to think about calculating the stage acceleration signal through the relative position and base plate acceleration signals. So that there will be no need to use stage accelerometer, which results in the cost-effectiveness of the control system and safety of the setup. The experimental results show almost the same performances for the proposed PDD~2 controller as achieved through the conventional one.
    关键词:控制器;气动定位;PDD ~ 2控制器;刚度;阻尼环
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