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991.
为加强轮机人员对电力系统知识的掌握,根据现代大型集装箱船电力系统的特点,详细介绍了船舶应急电系统受控的逻辑关系,特别指出联络开关的意义和作用,可为船舶电站设计、轮机设备维护管理及故障分析提供指导。 相似文献
992.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(11):795-806
Two typical criteria for good vehicle suspension performance are their ability to provide good road handling and increased passenger comfort. The main disturbance affecting these two criteria is terrain irregularities. Active suspension control systems reduce these undesirable effects by isolating car body motion from vibrations at the wheels. This paper describes fuzzy and adaptive fuzzy control (AFC) schemes for the automobile active suspension system (ASS). The design objective is to provide smooth vertical motion so as to achieve the road holding and riding comfort over a wide range of road profiles. The efficacy of the proposed control schemes is demonstrated via simulations. With respect to the optimal linear quadratic regulator (LQR), it is shown that superior results have been achieved by the AFC. 相似文献
993.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(5):675-697
This paper presents a closed-loop dynamic simulation-based design method for articulated heavy vehicles (AHVs) with active trailer steering (ATS) systems. AHVs have poor manoeuvrability at low speeds and exhibit low lateral stability at high speeds. From the design point of view, there exists a trade-off relationship between AHVs’ manoeuvrability and stability. For example, fewer articulation points and longer wheelbases will improve high-speed lateral stability, but they will degrade low-speed manoeuvrability. To tackle this conflicting design problem, a systematic method is proposed for the design of AHVs with ATS systems. In order to evaluate vehicle performance measures under a well-defined testing manoeuvre, a driver model is introduced and it ‘drivers’ the vehicle model to follow a prescribed route at a given speed. Considering the interactions between the mechanical trailer and the ATS system, the proposed design method simultaneously optimises the active design variables of the controllers and passive design variables of the trailer in a single design loop (SDL). Through the design optimisation of an ATS system for an AHV with a truck and a drawbar trailer combination, this SDL method is compared against a published two design loop method. The benchmark investigation shows that the former can determine better trade-off design solutions than those derived by the latter. This SDL method provides an effective approach to automatically implement the design synthesis of AHVs with ATS systems. 相似文献
994.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(6):856-876
The bodies of many railway freight cars in many countries of the world are coupled to the running gear by means of a body centre plate that makes a friction pair with a centre bowl. During motion, the bogie is rotated and moved with respect to the car body. This leads to wear on the contact surfaces. Lubrication is inexpedient in this case because the friction forces damp the vibrations (so-called bogie hunting) during motion. Usually, centre plates exhibit noticeable wear after two years of operation. Reducing wear requires knowing details of the wear process which, in turn, requires computer simulation of freight car motion for an operation period of 10–15 years. The purpose of this paper is to develop a universal method for wear simulation of friction pairs that could be used, in particular, for the centre plate of a freight car. 相似文献
995.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(9):1477-1496
This work presents a virtual rider for the guidance of a nonlinear motorcycle model. The target motion is defined in terms of roll angle and speed. The virtual rider inputs are the steering torque, the rear-wheel driving/braking torque and front-wheel braking torque. The virtual rider capability is assessed by guiding the nonlinear motorcycle model in demanding manoeuvres with roll angles of 50° and longitudinal accelerations up to 0.8 g. Considerations on the effective preview distance used by the virtual rider are included. 相似文献
996.
介绍了多电平变换技术的发展,对多电平逆变器的电路结构以及控制策略进行了分析和比较,指出了其优缺点.最后介绍了多电平逆变技术在高电压大功率的变频调速、有源电力滤波装置和电力系统无功补偿等方面的应用情况. 相似文献
997.
本文结合二连浩特至赛罕塔拉一级公路工程实例,分析了水泥稳定碎石基层平整度的影响因素,介绍本项目如何提高水泥稳定碎石基层平整度的综合控制措施。 相似文献
998.
结合观音桥枢纽互通B匝道桥工程实例,对连续梁桥悬臂施工的施工控制过程模拟、施工控制中的现场监测项目与监测方法等进行了介绍,并对施工中需注意的事项提出几点建议。 相似文献
999.
1000.
青藏高原铁路客车电气系统设计 总被引:2,自引:0,他引:2
文章从安全性和可靠性的角度出发,指出了青藏高原铁路客车电气系统需要解决的难题,介绍了电气系统及设备所采取的针对性措施以及系统控制与防护措施。 相似文献