【作者】 周星；

【导师】 丁凡；

【作者基本信息】 浙江大学 ， 机械电子工程， 2012， 硕士

【摘要】 比例电磁铁作为电液比例控制元件中实现电信号与机械信号转换的核心部件,在国防及工业各领域的电液控制系统中承担着重要作用。传统比例电磁铁的隔磁环部分一般由手工焊接,劳动强度大,加工工艺复杂,不利于先进自动化制造技术的推广和实现,不能满足现代工业对可持续发展的需求。基于磁栅式导磁套比例电磁铁的研究将更有利于实现自动化生产,从而解决目前企业技术工人缺乏的困境,更好地满足日益提高的市场需求,进而推动相关领域理论与技术的发展。本文以基于磁栅式导磁套的比例电磁铁关键技术为研究对象,以简化工艺、降低成本、提高性能为研究目标,采用理论分析、解析计算、数值仿真以及试验研究相结合的方法,对该新型电磁铁的关键技术进行了系统分析和深入研究。文中针对传统比例电磁铁隔磁环结构制造工艺复杂、电磁铁加工质量不稳定、加工成本较高的缺陷,提出了一种基于磁栅式导磁套的新型比例电磁铁结构,并完成了设计；根据磁路分析和磁场有限元仿真,分别探讨了各结构参数对电磁铁性能的作用机理和匹配关系；根据电磁铁温度场模型及应力分析设计理论,分别对其进行了温升验证和导磁套强度验证；搭建了比例电磁铁力测试系统,完成了基于磁栅式导磁套比例电磁铁的动静态试验。试验结果表明,其额定行程为3.6mm,额定输出力为54N,输出力滞环小于2.7%,电流滞环在2.2%左右,幅频宽约为50 Hz,具有良好的动静态特性。有关各章节内容分述如下：第一章从电液伺服／比例阀用电—机械转换器的角度出发,阐述了比例电磁铁关键技术的国内外研究进展,分析总结了阀用电—机械转换器的结构、工作原理、分类以及发展趋势。第二章针对广泛应用的典型比例电磁铁,介绍了其结构组成及工作原理；基于相关磁路定律和磁场理论,分别阐述了比例电磁铁磁路分析法和磁场数值计算方法的特点及应用场合；建立了线圈激磁磁路静态模型、比例电磁铁动态数学模型以及有限元瞬态场数学模型,得到电磁输出力的解析式和有限元方程。第三章提出了一种基于磁栅式导磁套的比例电磁铁结构,分析了其结构优点和工作原理；通过磁路分析及有限元仿真,详细阐述了各结构参数对其静态特性的作用机理,得到优化参数值下的比例电磁铁动静态特性仿真曲线；根据电磁铁发热机理,建立了稳态线圈温升模型以及瞬态温度场有限元模型,仿真验证了基于磁栅式导磁套的比例电磁铁各部分温升均在相应材料的许可范围内；基于应力分析设计法,建立了一体式导磁套强度分析有限元模型,对其进行仿真及等效线性化处理,根据应力分类与应力评判标准对线性化处理结果进行应力强度评定,验证了导磁套能够承受足够的内部压力。第四章搭建了电磁铁力特性测试系统,介绍了其组成、原理以及电磁铁的性能指标和试验方法；研制了基于磁栅式导磁套的比例电磁铁样机,基于搭建的测试系统对其静动态性能进行了试验研究,获得了电磁铁的动静态试验结果,并与仿真结果进行了对比,验证了静态磁场有限元模型的准确性。第五章对全文的主要研究工作和成果进行概括,并针对不足之处展望了今后需要进一步研究的工作和方向。更多还原

【Abstract】 As key components of electrohydraulic servo/proportional valves, the proportional electromagnet plays an important role in electric-hydraulic systems in both military and civil industry. The magnetic isolation ring of traditional proportional electromagnet is usually made manully, which is labor-intensive, process-perplexed, high-cost and easy to form gas cavity. For this reason, it cannot satisfy the standard of sustainable development of modern industry. The new proportional electromagnet with magnet-grid sleeve can effectively simplify the process and reduce costs, which is good for automated production. Furthermore, it can solve the widespread problem of shortage of workers, better satisfy the booming market demand, and promot the development of related theory and technology.For the target of simplifying the process, reducing cost, and improving the performance, the key technologies of the new proportional electromagnet with magnet-grid sleeve are systematically, deeply researched, based on theory analysis, analytical calcution, numerical simulation and experimental study. To solve the problem of high cost and sophisticated process of traditional proportional electromagnet sleeve, a novel proportional electromagnet is proposed, in which the single piece sleeve by magnetic-grid structure is adopted. Based on the magnetic analysis and simulation, the influence of various structural parameters is presented in detail. And based on the temperature field model and the stress analysis and design theory, the temperature rise and the intensity of the sleeve are verified. The results of simulation and test of the new proportional electromagnet with magnet-grid sleeve show that the new proportional electromagnet has good static and dynamic characteristics, with a linear working range of 3.6mm, a rated output force of 54N, an output foce hysteresis of less than 2.7%, an electric current hysteresis of 2.2%, and a 50Hz frequency response.The main content of each chapter is summarized as following:In chapter 1, from standpoints of the electromechanical converters for the electrohydraulic servo/proportional valves, the research progress on the key technologies of proportional electromagnet is introduced. The structural, principal, classification, development trend of the electromechanical converters for valves are summarized.In chapter 2, the typical structure and the working principle of the widely used proportional electromagnet are introduced. Based on the related laws of magnetic circuit and magnetic field theory, the characteristics and applications of magnetic circuit analysis method and numerical magnetic field method are introduced separately. The static model of the coil magnetic excitation, the dynamic model and the finite element method model of the proportional electromagnet are established, ande based on which the analytic equation of magnetic output force and the equation of finite element are obtained. In chapter 3, a new proportional electromagnet with magnet-grid sleeve is proposed, the structural advantages and working principles of which are analysed. Based on the analysis and finite element simulation of magnetic circuit, the effects of various structural parameters are deeply analysed, and the static characteristic simulation curves of the proportional electromagnet are obtained. Based on the principles of heat and magnetics, the temperature rise model and the transient temperature field finite element model of the coil are established, and the results of simulation show that the temperature rise is in the working range of the materials. Based on the stress analysis ande design method, the finite element model of the single-piece sleeve is established, simulated ande linearized. And according to the stress classification and stress assessment law, the linearization result shows that the sleeve can endure internal pressure which is large enough.In chapter 4, the constitution and principal of a test system for force characteristics, the performances and test methods of proportional electromagnet are introduced. A proportional electromagnet with magnet-grid sleeve is designed and made, the static and dynamic characteristics of which are tested by the test system. The static and dynamic test results of the proportional electromagnet with magnet-grid sleeve are compared with the simulation results, and the static magnetic field finite element model is verified.In chapter 5, all achievements of the dissertation are summarized and the further research work is put forward.更多还原