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基于QFT的电液力伺服系统的鲁棒控制 总被引:3,自引:2,他引:3
采用QFT方法,对电液伺服加载系统进行了鲁棒控制器设计。结果表明,控制器能够有效地抑制参数扰动,如弹性负载刚度变化、有效体积弹性模数变化等。控制器结构简单,工程上易于实现,有较高的实用价值。 相似文献
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In an electro-hydraulic servo control system, the force servo system is an important component. However, due to the nonlinear characteristic of hydraulic systems, traditional control methods cannot achieve satisfactory control performances. To deal with this issue, a load velocity compensation algorithm based on the structural invariant principle is proposed in this paper. First, the theoretical analysis of the hydraulic and cylindrical force control system is presented, and the mathematical model of the force control system is established. Then the open-loop frequency response characteristics of the system are analyzed, in which the Bode diagram shows that the bandwidth of the system is obviously expanded after adopting the load velocity compensation algorithm. Finally, a practical hydraulic and cylindrical force servo system is introduced to validate the feasibility of the proposed controller, the experimental results demonstrate that the proposed method can improve the performance of force control and eliminate the influence of load stiffness on the dynamic characteristics of the system through a set of comparative experiments with different elastic loads. 相似文献
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四轮轮毂电机驱动电动汽车电液复合制动平顺性控制策略 总被引:3,自引:1,他引:2
液压制动与电机再生制动的时域响应差异导致电动汽车在制动模式切换时产生冲击感,影响驾驶员驾驶感受和乘坐舒适性。以四轮轮毂电机驱动电动汽车为研究对象,提出一种基于分层架构的电液复合制动平顺性控制策略。针对"高压蓄能器+电机泵"式电子液压制动系统(EHB),上层控制器提出基于模糊控制的轮缸压力控制策略;针对制动模式切换过程中产生的冲击,下层控制器提出包括液压介入预测模块和电机制动补偿模块的电液复合制动平顺性控制策略。通过Simulink-AMESim联合仿真平台进行仿真试验验证。结果表明,轮缸压力控制策略能够保证轮缸液压力较好地追随目标压力,且稳态误差不超过2%;电液复合制动平顺性控制策略能够有效提高制动系统的响应速度,同时显著降低制动模式切换时的冲击,能提升车辆制动平顺性和乘坐舒适性。 相似文献
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DYNAMIC CHARACTERISTICS OF LARGE FLOW RATING ELECTRO- HYDRAULIC PROPORTIONAL CARTRIDGE VALVE 总被引:2,自引:0,他引:2
FU Linjian WEI Jianhua QIU Minxiu 《机械工程学报(英文版)》2008,21(6):57-62
A kind of cartridge servo proportional valve is discussed, which can be used for controlling large flow rate with high performance. By analyzing the structure principle of the valve, the transfer fimction of the valve is derived. With the transfer function, some structure elements that may affect its performance are investigated. Through the numerical simulation and test study, some principles of optimality and effective methods for improving the dynamic performance of the valve are proposed. The test results conform to the results of the theoretical analysis and simulation, which proves the correctness of the study and simulation works. The paper provides theoretical basis for engineering applications and series expanding design works 相似文献
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就德国西门子公司SIMADYND数字式电液控制系统的配置与功能进行了概述,同时就该系统在广东国华粤电台山发电有限公司国产600MW汽轮机的首次应用情况及在试运行过程中出现的主要问题进行介绍,并提出了相应的改进处理措施。 相似文献
28.
Friction characteristics of a new type of continuous rotary electro-hydraulic servomotor applied to simulator 总被引:1,自引:0,他引:1
The principle of a new type of no-pulsation continuous rotary electro-hydraulic servomotor applied to simulators is introduced. LuGre friction model was analyzed. The identification method of LuGre parameters was proposed, and the measures to compensate the effect of friction forces were given. A friction torque model for the new rotary motor was proposed. The low-speed response and step response of the motor were studied experimentally. Experimental results proved that using friction compensation could eliminate stick-slip motion at the low speed, which makes the servomotor applicable to simulators. 相似文献
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