Abstract
This paper analyzes the measurement error, caused by the position of the current-carrying conductor, of a circular array of magnetic sensors for current measurement. The circular array of magnetic sensors is an effective approach for AC or DC non-contact measurement, as it is low-cost, light-weight, has a large linear range, wide bandwidth, and low noise. Especially, it has been claimed that such structure has excellent reduction ability for errors caused by the position of the current-carrying conductor, crosstalk current interference, shape of the conduction cross-section, and the Earth’s magnetic field. However, the positions of the current-carrying conductor—including un-centeredness and un-perpendicularity—have not been analyzed in detail until now. In this paper, for the purpose of having minimum measurement error, a theoretical analysis has been proposed based on vector inner and exterior product. In the presented mathematical model of relative error, the un-center offset distance, the un-perpendicular angle, the radius of the circle, and the number of magnetic sensors are expressed in one equation. The comparison of the relative error caused by the position of the current-carrying conductor between four and eight sensors is conducted. Tunnel magnetoresistance (TMR) sensors are used in the experimental prototype to verify the mathematical model. The analysis results can be the reference to design the details of the circular array of magnetic sensors for current measurement in practical situations.
Highlights
The non-contact current measurement technology are continuously developing
It can be seen that the differences between the eight Tunnel magnetoresistance (TMR) sensors are obvious, which exist in other kinds of magnetic sensors (e.g., Giant magnetoresistance (GMR) sensors, Anisotropic magnetoresistance (AMR) sensors, or Hall sensors)
We analyzed the relative measurement error of a circular array of magnetic sensors caused by position error of the current-carrying conductor in this paper
Summary
The non-contact current measurement technology are continuously developing. One hand, high performed linear magnetic sensor and signal conditioning IC for closed—loop magnetic current sensor have been lunched, e.g., DRV5055 and DRV401-EP form TI. In order to improve the measurement accuracy, the structure based on a circular array of magnetic sensors has being frequently studied during the past two decades [3,4,5,6,7,8,9,10,11,12]. [13]), the circular array of magnetic sensors is considered to be an effective scheme to achieve low-cost, large linear range, wide frequency bandwidth [14,15,16], light weight, and high reliability. The circular array of magnetic sensors can be used for both DC and high-frequency AC measurement, compared to Rogowski coil [17], which can only be used for high-frequency and low frequency (50/60) current measurement. The measurement accuracy of this structure mainly suffers from the error caused by position of the current-carrying conductor
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.