Optimalizace snímačů proudu s Hallovou sondou a Rogowského cívkou

Kaushal Singara Chari

Master's thesis

Optimization of current sensors with Hall probe and Rogowski coil

Abstract:

The main aim of this thesis is to understand the working of 2 magnetic current sensors, the Rogowski coil and Hall sensor, and study the errors induced in these sensors due to geometrical asymmetries and changes in the position of the primary conductor. We created 2 mathematical models based on known analytical formulae to estimate the error in measurement due to the gap for the PCB Rogowski coil and the split core Rogowski coil for different positions of the primary conductor. The gap creates asymmetries in the geometry of the coil and the model showed that there is a drop in the induced voltage if the primary conductor is placed close to the gap and the voltage induced in the coil is found to higher if an external current carrying wire is placed close to the gap. We also created a mathematical model to estimate the error induced in Hall sensor due to changes in the position of the primary conductor based on the number of sensing elements surrounding the conductor. The model shows that the impact of primary conductor position can be reduced by increasing the number of sensing elements around the conductor. These models were validated by comparing the results to equivalent finite element models and also by measuring the error with some physical experiments.

Abstract:

The main aim of this thesis is to understand the working of 2 magnetic current sensors, the Rogowski coil and Hall sensor, and study the errors induced in these sensors due to geometrical asymmetries and changes in the position of the primary conductor. We created 2 mathematical models based on known analytical formulae to estimate the error in measurement due to the gap for the PCB Rogowski coil and the split core Rogowski coil for different positions of the primary conductor. The gap creates asymmetries in the geometry of the coil and the model showed that there is a drop in the induced voltage if the primary conductor is placed close to the gap and the voltage induced in the coil is found to higher if an external current carrying wire is placed close to the gap. We also created a mathematical model to estimate the error induced in Hall sensor due to changes in the position of the primary conductor based on the number of sensing elements surrounding the conductor. The model shows that the impact of primary conductor position can be reduced by increasing the number of sensing elements around the conductor. These models were validated by comparing the results to equivalent finite element models and also by measuring the error with some physical experiments.

Keywords

Faraday's law of electromagnetic induction, Biot-Savart's law, Hall effect, mathematical modelling, finite element modelling.

Language used: English

Date on which the thesis was submitted / produced: 30. 8. 2023

Thesis defence

• Supervisor: Ing. Miroslav Novák, Ph.D.

Technical University of Liberec

Faculty of Mechatronics, Informatics and Interdisciplinary Studies

Master programme / field:
Mechatronics / Mechatronics