IEEJ Journal of Industry Applications
Online ISSN : 2187-1108
Print ISSN : 2187-1094
ISSN-L : 2187-1094
Special Issue Paper
Signal Processing Design for Wide Bandwidth Hybrid Current Sensor based on Enhanced Analog Operational Amplifier Circuit
Philipp ZieglerMichael BuraJörg HaarerPhilipp MarxDavid HirningJörg Roth-Stielow
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2023 Volume 12 Issue 4 Pages 635-642


Hybrid current sensors are suitable for wide bandwidth current measurement. They entail the fusion of two different measurement circuits, one for DC and low-frequency current and another for high-frequency current. Thus, the advantages of the different measurement principles are incorporated in one current sensor. Hybrid current sensors generate output signals through a superposition of the signals from the low-frequency and high-frequency current sensors. This is realized using analog signal processing by means of an analog operational amplifier circuit. Realization of the superposition of the frequency responses of the different measurement circuits to achieve a constant gain in the transition area is challenging. This study focused on the analog signal processing and its enhancement. Specifically, two possible signal processing approaches to increase the bandwidth based on the state-of-the-art realization of a low-pass filter were devised. These approaches were investigated using a simulation model. Frequency response measurements using a hybrid current sensor based on tunneling magnetoresistance sensors and a Rogowski coil were used for verification. The results show that by enhancing the signal processing, the bandwidth of the current sensors can be significantly increased.

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© 2023 The Institute of Electrical Engineers of Japan
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