Magnetic Field Sensors for Linear Motor Position Determination
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Solution Overview
Problem
Existing methods for determining the position of engine parts, particularly in synchronous motors, face challenges when navigating curved paths with small radii, as they often require rigid structures and are prone to measurement errors due to gaps and irregularities.
Innovation Solution
A system utilizing magnetic field sensors arranged on a linear motor's primary part to detect the relative position of a secondary part with magnets spaced apart, employing majority voting and a three-phase design to generate undisturbed track signals, allowing for accurate position determination and smooth movement on curved paths without the need for a rigid secondary motor part.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If magnetic field sensors are used to determine position in synchronous motors, then position determination capability is improved, but measurement errors occur due to gaps and irregularities in the magnet arrangement
Solution Approach 1:
The patent divides the magnet arrangement into multiple separate magnets spaced apart along the movement direction, creating distinct magnetic field zones. This segmentation allows the system to handle gaps between magnets while maintaining position determination capability through multiple sensing points.
Solution Approach 2:
The patent combines signals from multiple magnetic field sensors using majority voting to determine the final position. By merging multiple measurements and selecting the majority result, the system eliminates errors caused by gaps or irregularities in the magnet arrangement, thereby improving measurement reliability.
2Stability of the object's composition
If a rigid secondary motor part is used to maintain structural stability, then structural stability is improved, but the motor part protrudes far from the track when driving through curves with small radii
Solution Approach 1:
The patent divides the secondary motor part into multiple separate units or modules that can be independently positioned. This segmentation allows each unit to follow the track curvature more closely while maintaining overall structural stability through their coordinated arrangement.
Solution Approach 2:
The patent enables the secondary motor part to adapt its configuration dynamically, allowing units to be arranged optimally for both straight and curved track sections. This dynamic arrangement reduces protrusion on curves while maintaining stability through the distributed unit structure.
3Ease of manufacture
If magnets are spaced apart in the direction of movement to allow flexible assembly, then ease of manufacture is improved, but measurement errors are introduced due to gaps
Solution Approach 1:
The patent intentionally segments the magnet arrangement with controlled gaps between magnets, enabling flexible assembly of the secondary motor part from separate units. This segmentation is compensated by using multiple sensors and majority voting to maintain measurement precision despite the gaps.
Solution Approach 2:
The patent applies different qualities to different regions: magnets are spaced apart in regions where assembly flexibility is needed, while maintaining sufficient magnetic field coverage in regions where position determination is critical. This local differentiation optimizes both manufacturability and measurement accuracy.
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
Enables precise position determination and reduced protrusion of the motor part from the track, even on curved paths with small radii, by eliminating measurement errors and allowing for flexible assembly of motor units, thereby improving propulsion force consistency and accuracy.
Implementation Method 1
the magnetic field strength generated or at least influenced by magnets of the second motor part being determined at several points on the first motor part
Data Source
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AI summary
Method and system for determining the position of a first motor part of an electric motor relative to a second motor part of the electric motor, wherein the magnetic field strength generated or at least influenced by magnets of the second motor part is determined at several points on the first motor part, and the relative position of the second to the first motor part is determined from this, wherein the magnetic field strength is determined locally at several points on the first motor part, wherein the points are spaced apart from each other in the direction of movement, wherein each point is assigned to one of at least two groups, wherein a respective signal value is determined from the values belonging to a group by majority decision, and the position is determined from the signal values.