【作者】 李其朋；

【导师】 丁凡；

【作者基本信息】 浙江大学 ， 机械电子控制工程， 2005， 博士

【摘要】 电液伺服控制系统以其控制精度高、响应速度快、抗负载刚性大等优点，在航空航天领域如导弹、火箭等的模拟加载装置，冶金领域如纠偏机构、张力控制机构，军事领域如火炮控制机构，工程机械领域如推土机、压路机等都有着广泛的应用。电液伺服阀作为电液伺服控制系统的核心部件，其作用是将输入的小功率电信号精确快速的转换为大功率的液压能输出，其性能优劣直接决定着电液控制系统的性能。直动式电液伺服阀因其具有结构简单、响应快、抗污染能力强、可靠性高、无先导级泄漏、特性不受供油压力影响等性能优点，已经成为流体传动与控制领域的一个重要发展方向和竞争焦点。提高电液伺服阀的性能指标，有助于改善电液伺服控制系统的控制特性，有益于更好地满足日益提高的市场需求，进而推动流体传动及控制技术的发展。 论文以直动式电液伺服阀的关键技术为研究对象，在综合国内外文献的基础上，提出了永磁极化、差动磁通驱动、动铁式、耐高压双向电-机械转换器的新结构，通过理论分析和磁场的有限元计算，确定了各结构参数间的匹配关系，实验结果表明该电-机械转换器的线性工作范围±1mm，最大驱动力为±60N，滞环小于2％，幅频宽达到160Hz。针对目前阀用电感式传感器的频响有限，已难满足高频响电液伺服阀的要求，本论文还提出了耐高压阀用电涡流位移传感器的新结构，并就电涡流传感器易温度漂移的技术难点，在理论分析基础上，提出采用无感线圈进行温度补偿的新方法，仿真和实验结果表明，该位移传感器的测量量程为8mm，精度为0.5％，20～90℃测量范围内温升引起的测量偏差由未补偿时的12％降低到0.7％，频响高，能够满足高频电液伺服阀的性能要求。基于耐高压双向电-机械转换器和耐高压电涡流位移传感器，本论文研制了不带位移反馈以及带位移反馈的直动式电液伺服阀的新结构，仿真探讨了其结构参数与其输出特性的内在关系，实验研究了直动式电液伺服阀的输出特性，实验结果表明，该直动式电液伺服阀的额定压力为21MPa，额定流量为60L／min，额定电流为±2A，滞环小于7％(不带位移反馈)，幅频宽达到100Hz(10％额定流量@-3dB)。 有关各章内容分述如下： 第一章，在综合国内外文献的基础上，介绍了电液伺服阀的发展历史，从新结构和新材料两个角度论述了国内外电液伺服阀的研究动态，重点介绍了电液伺服阀的工作原理和性能指标；介绍了伺服阀相关技术，包括冷却技术、位移反馈技术以及液动力补偿技术的进展，总结出电液伺服阀的若干发展趋势。 第二章，介绍了传统型和新材料型两类电-机械转换器的作用、分类及工作原理，并进行了性能比较；分析讨论了单向比例电磁铁的输出特性及工作机理，深入探讨了其结构参数与其输出特性的关系及作用规律；在此基础上，提出了永磁极化式双向电-机械转换器，并就其关键技术包括永磁材料、软磁材料、衔铁支承以及激励线圈等给以了分析讨论。更多还原

【Abstract】 As an important approach to automatic control, electrohydraulic servo control system has been widely used in many sections of national economy and social surroundings due to its advantages such as high level of control precision, quick response speed and high immunity to load variations. Electrohydraulic servo valves, the key part of an EHC servo system, with its function of transferring low-power electrical signal to large-power hydraulic output quickly and precisely, play an essential role in deciding the whole performance of the system. Direct-drive servo valve has come to be an important trend in fluid power transmission and control, in that it has advantages like compact structure, quick response, strong immunity to pollution, strong reliability, no leakage in pilot stage and no influence of supply pressure to performance. Therefore, improving its performance, can be beneficial to enhancing the control performance of the EHC servo system, better satisfying the market requirements and pushing forward the fluid power technology.The thesis deep analyzed and researched the direct-drive servo valve, utilizing theory analysis, computer simulation, finite element numerical computation and experimental study. A permanent-magnet polarized, differential controlled, moving-iron type, high pressure, bi-directional electrical-mechanical converter is put forward, the matching relation between its structure parameters is determined by simulation, and the experimental results indicate that the converter has a linear working range of ± 1mm, hysteresis lower than 2%, and frequency response 160Hz. A high-pressure eddy current displacement sensor is presented, and a temperature-drift compensation method employing non-inductive coil is also brought forward through theoretical analysis on the causes of temperature drift, both the simulated and experimental results show that the sensor has an effective range of 8mm, precision of 0.5%, frequency response of 500Hz. Finally, two types of direct-drive servo valve, one with and one without displacement feedback, are raised, then the matching relation between the structure parameters and the performance are discussed, and experiments are carried out, both the simulated and experimental results prove that the valves have achieved excellent characteristics, with nominal pressure 21MPa, nominal flow 40L/min, nominal electrical current 2A, hysteresis lower than 7% (without position feedback) and 3% (with position feedback), frequency response 120Hz.In chapter 1, based on the research information abroad and overseas, the history of the servo valve is introduced, and the present technical status, especially the structure and performance of every kind, is described in the term of new structure and new material, the related technologies including cooling technology, position feedback technology and flow force compensation are both reported, finally, some trends on the development of the servo valve are summarized.In chapter 2, the traditional and new-type electrical-mechanical converters are compared on their function, classification and working principle; the performance and working mechanism of the proportional solenoid are illustrated, and furthermore, the relation between its parameters and its characteristics are discussed; then a novel permanent-magnet polarized bi-directional linear actuator is presented, and its key technology including permanent magnet material, soft magnet material, armature and excitation coil are analyzed.In chapter 3, based on finite element analysis, considering the magnetic leakage and non-linear magnet characteristics, the static mathematical model is established, and the influence of the parameters on the performance are given, then the model is confirmed by experiments. The electrical-magnetic-mechanical coupling of the actuator’s dynamic procedure is analyzed, and the transient performance of the actuator is calculated employing direct coupling method, the influence of the electrical and mechanical parameters on更多还原