基于有限元法的极化磁系统等效磁路模型的研究
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摘要
航天电磁继电器是国防电子系统中主要的电子元器件之一。极化磁系统以其灵敏度高、功耗低、体积小、动作快和电寿命长等一系列优点,被广泛应用于航天电磁继电器产品中。含永磁磁系统吸力特性分析是进行继电器磁系统参数化设计的基础,对于永磁的恰当处理和计算是准确分析吸力特性的前提。
由于永磁内部磁通分布不均匀,极化磁系统中各段永磁工作在不同的回复线上,为了对各段永磁进行等效,首先需要求出各段永磁的起始工作点。根据永磁的不同装配方式,分别对永磁“开路”情况和完全装配情况进行三维磁场仿真分析,计算永磁各截面的磁通,获得永磁各段中心截面的平均磁感应强度,将其作为各段永磁的起始工作点对应的磁感应强度值。研制永磁截面磁通测量装置,对三维磁场仿真分析结果进行验证。
为了提高等效磁路模型的精度,需要得到计算精度较高的永磁漏磁导。利用有限元软件获得条形永磁开路及装配情况下磁场分布情况,“开路”情况下永磁在空气中的漏磁通管为新月形截面,并将计算出的漏磁导与磁场仿真结果及实验计算结果进行比较;完全装配情况下永磁漏磁通包括经过空气闭合及经过轭铁闭合两种情况,经过空气闭合的漏磁通管为新月形截面,经过轭铁闭合的漏磁通管可分为柱形截面、部分圆环形截面、不同心圆环形截面三种,将计算出的漏磁导与磁场仿真结果进行比较;给出永磁漏磁通经不同介质闭合的分界面确定方法。
利用三维有限元方法获得不同装配情况下永磁的磁场分布情况,并按照磁场分布对永磁进行合理分段,利用磁场仿真结果计算出各段永磁的工作回复线,给出各段永磁等效磁势与等效磁阻的计算方法。在此基础上建立永磁分段后的等效磁路模型。利用该模型建立方法为现有产品及实验模型建立等效磁路模型,计算出吸力特性,并与实验结果、有限元方法及未分段等效磁路方法计算结果进行比较。
Electromagnetic relay in aerospace is one of main electronic components in national defense weapon equipment system. Polarized magnetic system is widely used in electromagnetic relay in aerospace as it has a series of features, such as high-sensitivity, low power consumption, small volume, quick movement, long electrical life and so on. The analysis of electromagnetic attractive force characteristic of magnetic system with permanent magnet is a foundation for the parameter design in relay’s magnetic system, whether the permanent magnet is treated and calculated appropriately or not is the precondition to analyze the electromagnetic attractive force characteristic accurately.
The different parts of PM don’t work on the same recoil line because of the uneven PM’s internal magnetic field distribution. Initial work points of each section of PM are calculated to conduct equivalent magnetic models. According to different ways of permanent magnet assembly, analyses of 3d magnetic field simulation are used to simulate PM in air and PM in whole magnetic system. Magnetic flux density distribution of PM’s sections is obtained by post processing simulation result and can be used to obtain the characteristic of the magnetic flux density distribution curve. The value of B corresponding to initial work point for each part is assigned the average magnetic flux density of this part. Internal magnet flux measurement device is developed to verify 3d magnetic field simulation results.
Calculation accuracy of equivalent magnetic circuit method could be effectively improved with exact calculation of PM leakage permeance. Magnetic field distributions of PM in air and PM in whole magnetic system can be obtained by FEM software. Cross-sections of leakage magnetic flux tubes of PM in air are close to crescent, leakage permeance calculated are compared with results calculated by simulation and measuring results; paths of leakage magnetic flux of PM in whole magnetic system are closed through the air or through the yoke. Cross-sections of leakage magnetic flux through the yoke can be divided into cylindrical section, partial circular annular cross-section and non-circular cross-section, leakage permeance calculated are compared with results calculated by simulation. Method of determining interface of PM leakage flux is provided.
Magnetic field distributions of PM in air and PM in whole magnetic system can be obtained by FEM software, and PM is divided into parts based on magnetic field distributions. Recoil lines of each section are calculated with simulation results. Calculation methods of equivalent magnetic potential and equivalent reluctance of PM subsection are provided. Equivalent magnetic circuit is established to calculate attractive force characteristics of existing product and experimental model, which are compared with simulation results, measuring results and traditional magnetic circuit model results.
由于永磁内部磁通分布不均匀,极化磁系统中各段永磁工作在不同的回复线上,为了对各段永磁进行等效,首先需要求出各段永磁的起始工作点。根据永磁的不同装配方式,分别对永磁“开路”情况和完全装配情况进行三维磁场仿真分析,计算永磁各截面的磁通,获得永磁各段中心截面的平均磁感应强度,将其作为各段永磁的起始工作点对应的磁感应强度值。研制永磁截面磁通测量装置,对三维磁场仿真分析结果进行验证。
为了提高等效磁路模型的精度,需要得到计算精度较高的永磁漏磁导。利用有限元软件获得条形永磁开路及装配情况下磁场分布情况,“开路”情况下永磁在空气中的漏磁通管为新月形截面,并将计算出的漏磁导与磁场仿真结果及实验计算结果进行比较;完全装配情况下永磁漏磁通包括经过空气闭合及经过轭铁闭合两种情况,经过空气闭合的漏磁通管为新月形截面,经过轭铁闭合的漏磁通管可分为柱形截面、部分圆环形截面、不同心圆环形截面三种,将计算出的漏磁导与磁场仿真结果进行比较;给出永磁漏磁通经不同介质闭合的分界面确定方法。
利用三维有限元方法获得不同装配情况下永磁的磁场分布情况,并按照磁场分布对永磁进行合理分段,利用磁场仿真结果计算出各段永磁的工作回复线,给出各段永磁等效磁势与等效磁阻的计算方法。在此基础上建立永磁分段后的等效磁路模型。利用该模型建立方法为现有产品及实验模型建立等效磁路模型,计算出吸力特性,并与实验结果、有限元方法及未分段等效磁路方法计算结果进行比较。
Electromagnetic relay in aerospace is one of main electronic components in national defense weapon equipment system. Polarized magnetic system is widely used in electromagnetic relay in aerospace as it has a series of features, such as high-sensitivity, low power consumption, small volume, quick movement, long electrical life and so on. The analysis of electromagnetic attractive force characteristic of magnetic system with permanent magnet is a foundation for the parameter design in relay’s magnetic system, whether the permanent magnet is treated and calculated appropriately or not is the precondition to analyze the electromagnetic attractive force characteristic accurately.
The different parts of PM don’t work on the same recoil line because of the uneven PM’s internal magnetic field distribution. Initial work points of each section of PM are calculated to conduct equivalent magnetic models. According to different ways of permanent magnet assembly, analyses of 3d magnetic field simulation are used to simulate PM in air and PM in whole magnetic system. Magnetic flux density distribution of PM’s sections is obtained by post processing simulation result and can be used to obtain the characteristic of the magnetic flux density distribution curve. The value of B corresponding to initial work point for each part is assigned the average magnetic flux density of this part. Internal magnet flux measurement device is developed to verify 3d magnetic field simulation results.
Calculation accuracy of equivalent magnetic circuit method could be effectively improved with exact calculation of PM leakage permeance. Magnetic field distributions of PM in air and PM in whole magnetic system can be obtained by FEM software. Cross-sections of leakage magnetic flux tubes of PM in air are close to crescent, leakage permeance calculated are compared with results calculated by simulation and measuring results; paths of leakage magnetic flux of PM in whole magnetic system are closed through the air or through the yoke. Cross-sections of leakage magnetic flux through the yoke can be divided into cylindrical section, partial circular annular cross-section and non-circular cross-section, leakage permeance calculated are compared with results calculated by simulation. Method of determining interface of PM leakage flux is provided.
Magnetic field distributions of PM in air and PM in whole magnetic system can be obtained by FEM software, and PM is divided into parts based on magnetic field distributions. Recoil lines of each section are calculated with simulation results. Calculation methods of equivalent magnetic potential and equivalent reluctance of PM subsection are provided. Equivalent magnetic circuit is established to calculate attractive force characteristics of existing product and experimental model, which are compared with simulation results, measuring results and traditional magnetic circuit model results.
引文
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8 H. Saso. Super Small, High Insulation BA Relay Targets Information Processing Equipment. Journal of Electronic Engineering. 1995, (11):34~39
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2 Maosheng Ding, Gang Wang, Xiaohua Li. Reliability Analysis of Digital Relay. Eighth IEE International Conference on Developments in Power System Protection. 2004, (1):268~271
3 Jingying Zhao, Jianguo Lu, Haitao Wang, Guojin Liu. Study on Reliability Test Method of Overload Relay. Proceedings of the Fifty-second IEEE Holm Conference on Electrical Contacts. 2006, (9):58~62
4张冠生.电器理论基础.机械工业出版社, 1989:12~13
5周俊峰.继电器及其技术发展态势.机电元件. 2003, 23(2): 61~64
6朱永庆,吴世湘.军用继电器的发展态势.电子科学技术评论. 2005, (1):55~56
7 K J. Strnat. Modern Permanent Magnets for Application in Electro Technology. Proceedings of IEEE. 1990, 78(5):923~924
8 H. Saso. Super Small, High Insulation BA Relay Targets Information Processing Equipment. Journal of Electronic Engineering. 1995, (11):34~39
9 K. Karasawa. Technology in Place for Miniaturization, Enhance Sensitivity of Polarized Relays. Journal of Electronic Engineering. 1989, (11):58~60
10 Max Hurter. The Development of a High Reliability High G Shock Relay-Minitured Low Profile Relays. The 26th Annual National Relay Conference. 1978:4-1~4-8
11梁慧敏,叶雪荣,翟国富.军用电磁继电器容差设计可靠度计算方法.低压电器. 2005, (2):6~10
12佟为明,梁慧敏,刘宁滨,刘茂恺.极化磁系统永久磁铁回复线起始点的求法.电气电子教学学报. 1999, 21(2):25~28
13佟为明,赵志衡,刘茂恺.永磁磁路图解法.电气电子教学学报. 1997, 20(4):65~67
14李卫民,刘茂恺.归算漏磁导及采用漏磁法计算磁路.电杂志. 1991, (1):16~22
15张海云. JKB~56C继电器磁系统的分析与计算.北京航空航天大学科学研究报告. 1989:1~10
16 N. Sadowski, R. Carlson, A. M. Beckert and J. P. A. Bastos. Dynamic Modeling of a Newly Designed Linear Actuator Using 3D Edge Elements Analysis. IEEE Transactions on Magnetics. 1996, 32(3):1633~1636
17曲民兴,曹云东,孙鹏,来常学.稀土永磁在起重电磁铁中的应用.电气开关. 1994, (4):50~54
18沙德尚,孔力.一种分析双凸极电机非线性磁路的新方法.微特电机. 2005, (7):9~12
19董鲁宁,钱婧等.电磁推力轴承磁路计算方法的改进.上海大学学报. 2005, 11(4):375~380
20郑永成,王洋等.基于磁场分割的磁导计算与磁路设计.机械与电子. 2006, (7):11~13
21刘荣林.航空同步发电机的等效磁路模型.中国民航学院学报. 2004, 22(3): 18~20
22邹洪超,娄建勇,荣命哲.单线圈单稳态永磁机构接触器三维磁场分析和电磁吸力的计算.低压电器. 2004, (4):12~15
23张敬菽,陈德桂,向洪岗,刘刚,黄琳敏.直流接触器磁系统的动态特性计算及其可视化仿真.电工电能新技术. 2003, 22(3):28~31
24唐武进,耿英三,陈德桂等.基于三维有限元的直流接触器电磁系统特性计算.机床电器. 2004, (4):9~12
25 H. R. Bolton, Y. Shakweh. Performance prediction of Laws’s relay actuator. IEE PROCEEDINGS. 1990, 137(1):1~13
26 J. K. Kim, S. W. Joo, S. C. Hahn, J. P. Hong, D. H. Kang, and D. H. Koo. Static Characteristics of Linear BLDC Motor Using Equivalent Magnetic Circuit and Finite Element Method. IEEE Transactions on Magnetics. 2004,40(2):742~745
27佟为明,翟国富.低压电器继电器及其控制系统.哈尔滨工业大学出版社, 1999:189, 197
28王思民.极化磁系统中永磁体处理方法的改进.青岛科技大学学报(自然科学版). 28(3):234~236
29翟国富,梁慧敏,许峰,郝燕玲.电磁继电器可靠性容差设计方法的综合分析与讨论.低压电器. 2002, (6):12~16
30梁慧敏,张玉成,翟国富.电磁继电器静态吸反力特性测试方法的探讨.低压电器. 2003, (5):50~53
31翟国富,梁慧敏,郭成花等.极化磁系统永磁力矩特性曲线形状的分析与研究.中国电机工程学报. 2002, 22(11):110~114
32 SadowskiJ, Bastos P A, Albuquerque A B et al. A Voltage Fed AC Contactor Using 3D Edge Elements. IEEE Transactions on Magnetics. 1998, 34(5):3170~3173
33 Yoshihiro Kawase, Osamu Miyatani, Tadashi Yamaguchi et al. Numerical Analysis of Dynamic Characteristics of Electromagnets Using 3D Finite Element Method with Edge Elements. IEEE Transactions on Magnetics. 1994, 30(5):3248~3251
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