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本文通过理论分析,提出了感应电机提高转矩密度的实现途径。并通过理论推导,对利用谐波提高转矩密度进行了定性的理论分析。最后,通过有限元仿真和样机试验对比分析,对注入谐波提高转矩密度展开了验证,试验结果验证了部分理论的正确性。 相似文献
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为了解决由于单护盾TBM掘进刀盘扭矩过大或盾体姿态发生偏差时,管片在掘进过程中产生旋转,造成管片安装精度、外观质量及运输效率受到影响等问题,结合单护盾TBM在软岩地层掘进条件下,分析管片旋转产生的原因,针对刀盘等设备的结构进行设计改进、优化掘进参数、优选刀具类型、及时清理刀盘以及必要时采取牺牲管片环缝与纵缝等措施,最终解决了单护盾TBM掘进过程中管片旋转的施工难题。 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(10):1575-1596
Steering feel, or steering torque feedback, is widely regarded as an important aspect of the handling quality of a vehicle. Despite this, there is little theoretical understanding of its role. This paper describes an initial attempt to model the role of steering torque feedback arising from lateral tyre forces. The path-following control of a nonlinear vehicle model is implemented using a time-varying model predictive controller. A series of Kalman filters are used to represent the driver's ability to generate estimates of the system states from noisy sensory measurements, including the steering torque. It is found that under constant road friction conditions, the steering torque feedback reduces path-following errors provided the friction is sufficiently high to prevent frequent saturation of the tyres. When the driver model is extended to allow identification of, and adaptation to, a varying friction condition, it is found that the steering torque assists in the accurate identification of the friction condition. The simulation results give insight into the role of steering torque feedback arising from lateral tyre forces. The paper concludes with recommendations for further work. 相似文献
116.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(4):327-338
Via a conventional steering system the driver perceives desired and disturbing effects such as road feedback and resonance effects, respectively. They appear with overlapping frequency spectra within the driver's steering torque. This paper introduces a control algorithm that is suppressing periodic disturbances without affecting useful steering road feedback attributes as well as regular power assistance characteristic. This is realised by an integrated torque actuator within the steering column in conjunction with a conventional Hydraulic-assisted Power Steering (HPS) system. 相似文献
117.
为了较合理地估算刀盘的切削扭矩,对刀盘2种主要刀具即切刀和滚刀的切削扭矩进行研究:首先基于塑性力学中滑移线场,对滚刀和切刀分别建立与其切削机制相对应的塑性力学模型,推导具体的表达式;然后,根据盾构刀具的配置参数及红层掘进参数对刀盘的切削扭矩进行计算,分项求和得到刀盘总扭矩。最后对刀盘计算总扭矩与施工实测总扭矩相比较,并分析理论计算模型存在的误差原因。研究结果表明:滚刀在红层中受均匀磨损,磨损量小,刀盘扭矩的实际装备系数为3.2,有一定的富余。研究结果可为盾构刀盘的设计、施工提供参考。 相似文献
118.
Jan Loof Igo Besselink Henk Nijmeijer 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2019,57(1):86-107
This paper describes the coupling between a three degrees of freedom steering-system model and a multi-body truck model. The steering-system model includes the king-pin geometry to provide the correct feedback torque from the road to the steering-system. The steering-system model is combined with a validated tractor semi-trailer model. An instrumented tractor semi-trailer has been tested on a proving ground and the steering-wheel torque, pitman-arm angle, king-pin angles and drag-link force have been measured during steady-state cornering, a step steer input and a sinusoidal steering input. It is shown that the steering-system model is able to accurately predict the steering-wheel torque for all tests and the vehicle model is accurate for vehicle motions up to a frequency where the lateral acceleration gain is minimum. Even though the vehicle response is not accurate above this frequency, the steering-wheel torque is still represented accurately. 相似文献
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针对"两头忙"的工况特点,提出了目前在"两头忙"设计中常用的3种功率控制方式,并且介绍了其各自的工作原理和性能特点. 相似文献