Elihu Thomson´s jumping ring in a levitated closed-loop control experiment

Author

Barry, Noel ; Casey, Richard

Author_Institution

Dept. of Electr. & Electron. Eng., Cork Inst. of Technol., Ireland

Volume

42

Issue

1

fYear

1999

fDate

2/1/1999 12:00:00 AM

Firstpage

72

Lastpage

80

Abstract

A conducting nonmagnetic ring is levitated above a coil excited by an AC source, using the same principle as that of the well-known jumping ring experiment, originally discovered by Elihu Thomson. The AC source is amplitude modulated to ensure that the ring stays in a stationary levitated position. The circuit is analyzed using a simple electrical/magnetic treatment, and the parameters of the system are found. A control strategy is derived for the system, after it has been linearized for small perturbations about an operating point. A simple low-voltage implementation is also shown, with results

Keywords

closed loop systems; coils; control system analysis; magnetic forces; magnetic levitation; magnetic variables control; network analysis; AC source; Elihu Thomson; coil excitation; conducting nonmagnetic ring; control strategy; electrical/magnetic treatment; jumping ring; levitated closed-loop control experiment; low-voltage implementation; single phase linear actuator; stationary levitated position; Acceleration; Amplitude modulation; Circuit stability; Coils; Frequency; Gravity; Magnetic analysis; Magnetic levitation; Switches; Voltage;

fLanguage

English

Journal_Title

Education, IEEE Transactions on

Publisher

ieee

ISSN

0018-9359

Type

jour

DOI

10.1109/13.746338

Filename

746338