Nonlinearity Compensation of an Angular Position Encoder Using a Compact Linearization Circuit

XVII International Conference on Systems, Automatic Control and Measurements, SAUM 2024 (pp. 96-99)

АУТОР(И) / AUTHOR(S): Jelena Jovanović , Dragan Denić , Dragan Živanović , Ivana Ranđelović , Milan Dinčić , Goran Miljković 

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DOI:  10.46793/SAUM24.096J

САЖЕТАК / ABSTRACT:

This paper presents a compact linearization circuit designed to compensate for the nonlinearity of an angular position encoder. The circuit comprises two main sections: a preprocessing circuit that generates a modified sine signal from the encoder output signals, and a two-stage piecewise linear analog-to-digital converter of a compact design that performs nonlinearity compensation and digital conversion of the modified sine signal. Compactness is achieved by utilizing a single flash analog-to-digital converter for both conversion stages, thereby reducing the number of power-consuming comparators and production costs. LabVIEW simulations demonstrate a major reduction in both the maximal absolute nonlinearity error and the relative nonlinearity error of the measurement system. Before linearization, these errors were 0.33067 rad and 21.05%, respectively, but decreased to 0.00654 rad and 0.10403% after linearization with the proposed circuit.

КЉУЧНЕ РЕЧИ / KEYWORDS:

modified sine signal, flash ADC, compact design, comparator count, nonlinearity error

ПРОЈЕКАТ / ACKNOWLEDGEMENT:

This work was supported by the Ministry of Science, Technological Development and Innovation of the Repub-lic of Serbia [grant number 451-03-66/2024-03/200102].

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