High-Throughput Measurement of the Contact Resistance of Metal Electrode Materials and Uncertainty Estimation

Chao Zhang,Wanbin Ren

doi:10.3390/electronics9122079

Abstract

Low and stable contact resistance of metal electrode materials is mainly demanded for reliable and long lifetime electrical engineering. A novel test rig is developed in order to realize the high-throughput measurement of the contact resistance with the adjustable mechanical load force and load current. The contact potential drop is extracted accurately based on the proposed periodical current chopping (PCC) method in addition to the sliding window average filtering algorithm. The instrument is calibrated by standard resistors of 1 mΩ, 10 mΩ, and 100 mΩ with the accuracy of 0.01% and the associated measurement uncertainty is evaluated systematically. Furthermore, the contact resistance between standard indenter and rivet specimen is measured by the commercial DMM-based instruments and our designed test rig for comparison. The variations in relative expanded uncertainty of the measured contact resistance as a function of various mechanical load force and load current are presented.

Highlights

Metal electrode mAterials are widely used in the electrical and electronic engineering for conducting and/or switching current, such as connectors [1], electromechanical devices [2], thin-film devices [3], microelectromechanical system [4], and switchgear [5], etc
The contact resistance measurement has been successfully used to evaluate the conditions of mAin contacts and arcing contacts without dismantling the high voltage SF6 circuit breaker [6]
The results show that the error between the measured resistance and rated values of standard resistors under different current load is smaller than 1%, even including the low level measurement under dry circuit conditions where the contact current is limited to 1 mA and the contact potential drop on resistor of 1 mΩ is below 1 μV

Summary

Introduction

Metal electrode mAterials are widely used in the electrical and electronic engineering for conducting and/or switching current, such as connectors [1], electromechanical devices [2], thin-film devices [3], microelectromechanical system [4], and switchgear [5], etc. The roughness of the mAterial surfaces causes only small peaks or asperities within the apparent surface to be in contact. The induced constriction resistance and film resistance together mAke up the contact resistance. The optimal selection method for supporting electrode mAterial and contact resistance measuring method are needed to mAke them perfect. The contact resistance results could be selected as the criteria of contact mAterial surface quality, including roughness, hardness, or contamination situation [8,9]

Objectives

Discussion

Conclusion