Abstract
The purpose of this study is to investigate the temperature effect on system errors of a rotary magnetic encoder, such as pole-pitch error, magnetic field error, assembly error and AMR elements detecting error. An accuracy analysis in various aspects, including thermal expansion in 1mm pole-pitch, distance expansion between AMR array, and magnetic field changes due to the physical characteristics of encoder material. In consideration with the above requirement, an environmental test platform was constructed to conduct experiments and to measure system errors in the range of 10 to 75℃. Experiments were planned to check assembly errors occurring in various temperatures and verify the correctness of the mathematical model. The results indicated that the concentricity of the rotary encoder and measuring gap were relatively sensitive to this system when temperature was not in a standard condition. Finally, a relationship was established between temperature and encoder precision. It also provides advices for how to reduce the system errors of a rotary magnetic encoder in industrial applications.