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http://dx.doi.org/10.7471/ikeee.2015.19.3.335

An Implementation of High-precision Three-phase Linear Absolute Position Sensor  

Lee, Chang Su (The University of Suwon)
Publication Information
Journal of IKEEE / v.19, no.3, 2015 , pp. 335-341 More about this Journal
Abstract
Recently a demand for high precision absolute position transducer is increasing in order to control thickness in steel industry. LVDT (linear variable differential transformer) is widely used to measure the absolute position in the linearly moving cylinder under poor factory environment. In this paper we implement the three phase LVDT with a high resolution of one micron and L/D (LVDT to digital) converter. First we designed U, V, and W three phase signaling using FPGA. Second a pulse output algorithm is designed for position information with A and B phase waveforms. Finally the performance is compared with previous sensors. Experiments show that the linearity deviation error is 0.009788 [mm] and the average sinusoidal THD is 0.0751%, which means 2.2% and 33% more improved result than the previous sensors respectively.
Keywords
AWC/AGC; Three phase LVDT; L/D converter; FPGA; Linearity deviation error; THD;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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