Current Sensor Asymmetric Element Placement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional current sensors using magneto-electric conversion elements face challenges in achieving compact size and stable detection due to large inter-element spacings, which affect measurement precision and are prone to external magnetic field interference from adjacent current paths.
Innovation Solution
A current sensor design with symmetrically positioned magneto-electric conversion elements on a printed circuit board, where the sensitivity axes of each pair are oriented in parallel or opposite directions to minimize inter-element spacing and reduce external magnetic field effects, allowing for compact size and stable detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If magneto-electric conversion elements are positioned with large inter-element spacing to accommodate to-be-measured current path, then the current path can pass through easily, but measurement precision deteriorates and external magnetic field interference increases
Solution Approach 1:
The patent positions magneto-electric conversion elements asymmetrically relative to the to-be-measured current path, with different inter-element spacings on different sides. Elements closer to adjacent current paths are positioned farther away to reduce interference, while elements on the opposite side can be positioned closer to improve measurement precision. This asymmetric arrangement optimizes both current path accessibility and measurement accuracy.
Solution Approach 2:
The patent applies different positioning strategies for different magneto-electric conversion elements based on their local environment. Elements exposed to stronger external magnetic fields from adjacent current paths are positioned with larger spacing to reduce interference, while elements in less affected positions can maintain smaller spacing to improve overall measurement precision. Each element's position is optimized for its specific location.
2Measurement precision
If more magneto-electric conversion elements are added to improve measurement precision, then detection accuracy improves, but device complexity and size increase
Solution Approach 1:
Instead of symmetrically arranging multiple elements around the current path, the patent uses an asymmetric configuration where elements are positioned at different distances and angles. This allows achieving good measurement precision with fewer elements by strategically placing them where they provide maximum useful information while minimizing redundancy and complexity.
Solution Approach 2:
The patent positions magneto-electric conversion elements selectively at locations that provide the most critical measurement information, rather than uniformly distributing them. This partial action approach achieves sufficient measurement precision with a reduced number of elements, avoiding the complexity increase that would result from excessive element placement.
3Volume of moving object
If magneto-electric conversion elements are positioned close to reduce sensor size, then compactness is achieved, but sensitivity to external magnetic fields from adjacent current paths increases
Solution Approach 1:
The patent implements asymmetric positioning where inter-element spacing varies depending on the direction relative to adjacent current paths. Elements facing directions with stronger external magnetic field sources are positioned with larger spacing to reduce sensitivity to interference, while elements in directions with weaker interference can maintain smaller spacing to achieve compact overall sensor size.
Solution Approach 2:
The patent optimizes each magneto-electric conversion element's position based on its local magnetic field environment. Elements located in regions with higher external magnetic field intensity from adjacent current paths are given larger spacing to reduce sensitivity, while elements in lower interference regions maintain smaller spacing. This local optimization achieves compact dimensions without uniformly increasing spacing.
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
The design enables a compact current sensor with improved measurement precision and reduced sensitivity to external magnetic fields, maintaining stability even when adjacent current paths are present.
Implementation Method 1
magneto-electric conversion elements (here, Hall elements) 930 and 931 that output electronic signals according to the intensity of a magnetic filed generated by a current flowing in a conductor
Implementation Method 2
four magnetic impedance elements that are oppositely placed, centered around an electric wire holder
Data Source
AI summary
A current sensor includes magneto-electric conversion elements divided into a first and second group. The first and second groups are positioned so as to interpose a cut formed in a printed circuit board between them. The first and second groups are symmetrically positioned with respect to a first virtual line. The magneto-electric conversion elements in the first and second groups are symmetrically positioned with respect to a second virtual line orthogonal to the first virtual line at a positioning position at which a to-be-measured current path is positioned. The sensitivity axes of each of pairs of magneto-electric conversion elements that are symmetrical with respect to the positioning position are oriented in parallel in the same direction or opposite directions. An inter-element spacing between adjacent magneto-electric conversion elements in the first and second groups is narrower than an inter-group spacing, which is the narrowest spacing between the first and second groups.