U-Shaped Core Current Sensor with Recessed Portions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current sensors for hybrid vehicles and electric cars face errors in current measurement due to position deviations of the magnetic sensor, leading to increased stress and temperature drift, which affects the accuracy of current detection.
Innovation Solution
A current sensor configuration featuring a U-shaped core with recessed portions on both side surfaces facing the detection element, where the conductor is inserted into a slit and the detection element is positioned to minimize the impact of magnetic flux unevenness, even when the detection element deviates from its desired position.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the detection element is arranged in the groove portion of the core, then the magnetic sensor does not have to be molded in its entirety, minimizing stress and temperature drift, but the magnetic field strength significantly changes in the insertion direction of the conductor, increasing detection error when the sensor position deviates
Solution Approach 1:
The core is designed with a magnetic flux concentration portion that locally concentrates magnetic flux in the gap direction at the detection position of the detection element. This local modification creates a region of concentrated magnetic flux that compensates for position deviations, allowing the detection element to maintain high measurement precision even when not perfectly positioned. The local quality change (magnetic flux concentration) directly addresses the measurement precision issue while preserving the overall structure that minimizes temperature drift.
Solution Approach 2:
The magnetic flux concentration portion is pre-formed in the core during manufacturing, creating a predetermined magnetic flux distribution pattern before the detection element is installed. This preliminary action ensures that when the detection element is positioned in the groove, it automatically encounters the concentrated magnetic flux region, which compensates for any position deviations. The preliminary structuring of the magnetic path eliminates the need for precise positioning adjustments.
2Manufacturing precision
If the detection element is positioned to minimize stress on the magnetic sensor, then post-assembly offset fluctuation is reduced, but the magnetic field strength changes significantly with conductor position, increasing detection error
Solution Approach 1:
The magnetic flux concentration portion creates a localized region where magnetic flux is intensified in the gap direction. This local modification ensures that the detection element, regardless of its exact position within the groove, always detects from a region of concentrated magnetic flux. The local quality enhancement compensates for position variations, maintaining measurement precision while allowing the detection element to be positioned optimally for minimizing stress and offset fluctuation.
3Device complexity
If the core has a simple groove structure for conductor insertion, then the device complexity is reduced, but the magnetic field strength changes significantly in the insertion direction, making detection sensitive to position deviations
Solution Approach 1:
Rather than complicating the overall core structure, the invention introduces a localized magnetic flux concentration portion within the existing groove structure. This local modification concentrates magnetic flux specifically at the detection element's position without requiring major structural changes to the core. The simple groove structure is preserved for easy conductor insertion, while the local quality enhancement (magnetic flux concentration) provides the necessary field uniformity for accurate detection.
Solution Approach 2:
The magnetic flux concentration portion is designed to concentrate magnetic flux in the gap direction (perpendicular to the conductor insertion direction). By addressing the magnetic field distribution in this different dimension, the invention compensates for position deviations in the insertion direction without adding complexity to the mechanical structure. The magnetic flux concentration occurs in the dimensional space perpendicular to the conductor movement, providing error compensation without mechanical complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration reduces the change in magnetic field strength near the detection element, enhancing robustness against position deviations and ensuring accurate current measurement, thereby minimizing errors and stress on the sensor components.
Implementation Method 1
a detection element arranged in the slit of the core and detecting a magnetic field
Implementation Method 2
a U-shaped core as a magnetic body... the magnetic field strength of a gap-direction component of a magnetic field that is generated when the current flows through the conductor
Data Source
AI summary
A current sensor includes: a U-shaped core as a magnetic body; a conductor inserted into a slit of the core; and a detection element arranged in the slit of the core and detecting a magnetic field, wherein the core includes recessed portions on both side surfaces facing the detection element and the recessed portions have wall portions intersecting with at least an insertion direction of the conductor.