A synthetic position decoding technology for rotary transformers based rotor position measurement system

Jun Cai; Xiaolan Dou; Zeyuan Liu; Adrian David Cheok; Yan Ying; Xin Zhang

doi:10.1063/5.0193514

A synthetic position decoding technology for rotary transformers based rotor position measurement system

Rev Sci Instrum. 2024 Apr 1;95(4):044706. doi: 10.1063/5.0193514.

Authors

Jun Cai^{1

2}, Xiaolan Dou¹, Zeyuan Liu³, Adrian David Cheok¹, Yan Ying¹, Xin Zhang⁴

Affiliations

¹ C-MEIC, CICAEET, and the School of Automation,Nanjing University of Information Science and Technology, Nanjing 210044, China.
² School of Mechanical and Electrical Engineering, Anhui Jianzhu University, 230601 Hefei, China.
³ School of Automation, Nanjing University of Posts and Telecommunications, 210023 Nanjing, China.
⁴ Department of Electrical Engineering, Zhejiang University, 310013 Hangzhou, China.

PMID: 38661484
DOI: 10.1063/5.0193514

Abstract

This article proposes a rotary transformer position decoding scheme for motor drive control. In this scheme, a simple analog circuit is used to design the excitation circuit and signal conditioning circuit. Demodulate the modulated sine/cosine signal through software and decode it through a phase locked loop (PLL) to obtain the implemented position signal. This scheme completely avoids the use of traditional, specialized decoding chips. At the same time, in order to make the position decoding scheme applicable to different motor drive control platforms, a single-cycle partition average based pulse signal estimation method is proposed for converting the angle position into pulse signals similar to the output of an encoder's phases A, B, and Z, which are referred to as A/B/Z signals in the paper. In order to experimentally validate the proposed scheme, a software decoding platform based on the STM32F407 was built and compared with the decoding results of the chip. The effectiveness and accuracy of the proposed scheme were verified, and it can be effectively applied in the field of motor drive control.