Filtering algorithm and direction identification in relative position estimation based on induction loop-cable

Abstract

A filtering algorithm and direction identification method are presented for the positioning system of the mid-speed maglev train. Considering the special structure of the mid-speed maglev train, the ground position estimation method is adopted for its traction system. As the train is running, the induction loop-cable receives the signal sent by the on-board antenna to detect the position and direction of the train. But the height of the on-board antenna relative to the loop-cable is highly vulnerable to the change of the suspension height and the magnetic field produced by the traction during traveling, which may lead to amplitude fluctuation of the received signal. Consequently, the position estimation may be inaccurate. Therefore, a discrete second-order nonlinear trackdifferentiator is proposed based on the boundary characteristic curves, and the new differentiator could also extract the running direction of the train for the traction system. The experimental results show that the tracking differentiator can effectively filter out the signal interference and can provide accurate direction signal.

Keywords

maglev train / positioning system / loop-cable / tracking-differentiator (TD) / direction identification

References

[1] WuX MMaglev train [M], 2008Shanghai, ChinaShanghai Science and Technology Publishing House1808-1811

[2] LeeH-w, KimK-c, LeeJu. Review of maglev train technologies [J]. IEEE Transactions on Magnetics, 2006, 42(7): 1917-1925

[3] LiY, LiJ, ZhangGeng. Disturbance decoupled fault diagnosis for sensor fault of maglev suspension system [J]. Journal of Central South University, 2013, 20(6): 1545-1551

[4] ZhouH-b, DuanJ-an. Levitation mechanism modeling for maglev transportation system [J]. Journal of Central South University of Technology., 2010, 17(6): 1230-1237

[5] BellanP M. Simple system for locating ground loops [J]. Review of Scientific Instruments, 2007, 78: 065104

[6] SkibinskiG. Design methodology of cable terminator to reduce reflected voltage on AC motors [C]//. Conf Rec IEEE-IAS Annu Meeting, 1996153-161

[7] TheodoulidisT, BowlerJ. Eddy-current interaction of a long coil with a slot in a conductive plate [J]. IEEE Transaction on Magnetics, 2005, 41(4): 1238-1247

[8] MisronN, YingL Q, FirdausR N, AbdullahN. Effect of inductive coil shape on sensing performance of linear displacement sensor using thin inductive coil and pattern guide [J]. Sensors, 2011, 11: 10522-10533

[9] NorhisamM, NorrimahA, WagiranR, SidekR M, MariunN, WakiwakaH. Consideration of theoretical equation for output voltage of linear displacement sensor using meander coil and pattern guide [J]. Sensor and Actuators A, 2008, 147: 470-473

[10] DaiC H, LongZ Q, XieY D. Research on the filtering algorithm in speed and position detection of maglev trains [J]. Sensors, 2011, 7: 7402-7218

[11] HanJ Q. Auto disturbances rejection control technique [J]. Front Sci, 2007, 1: 24-31

[12] GuoB Z, ZhaoZ L. On convergence of tracking differentiator [J]. International Journal of Control, 2011, 84(4): 693-701

[13] XieY D, LongZ Q. A high-speed discrete tracking-differentiator with high precision [J]. Control Theory Appl, 2009, 26: 127-132

[14] XieY-d, LongZ-q, LiJie. Analysis of the second-order nonlinear discrete-time tracking-differentiator as a filtering [J]. Information and Automation, 2008785-789

[15] XieY D, LongZ Q, LiJ, LuoK. Research on a new nonlinear discrete-timetracking-differentiator filtering characteristic [C]//. Proceedings of the 7th World Congress on Intelligent Control and Automation, WCICA 2008, 20086750-6755

[16] XueS, LongZ-q, HeN, ChangW-sen. A high precision position sensor design and its signal processing algorithm for a maglev train [J]. Sensors, 2012, 12: 5225-5245