Flexible PCB Winding for Rotating Electrical Machine
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing windings for Brushless DC electric motors (BLDC) do not optimize performance, as they are limited to simple rectilinear segments and lack detailed designs for conductor connections between surfaces of flexible PCBs, which restricts the potential improvement in power density and efficiency.
Innovation Solution
The use of flexible PCB windings with conductors arranged in complex shapes, such as continuous curves or more than three rectilinear segments, and variable widths to optimize the torque constant and phase resistance ratio, along with specific connection modes that reduce overall conductor length and improve electrical insulation, are employed to enhance the performance of rotating electrical machines.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conductors are arranged in simple rectilinear segments (2-3 segments), then the manufacturing process is simple and easy to implement, but the performance of the electrical machine is not optimized
Solution Approach 1:
The patent applies curvature by transitioning from simple rectilinear conductor segments to complex curved trajectories. The conductors on the flexible PCB are designed to follow continuous curves or multiple rectilinear segments (n>3) that better match the optimal magnetic field distribution in the air gap, thereby improving power density while remaining manufacturable through standard PCB routing techniques.
Solution Approach 2:
The patent changes the geometric parameters of the conductor layout by increasing the number of segments from 2-3 to more than 3 segments, and by introducing variable width conductors. These parameter changes allow the winding to better approximate the optimal current distribution for radial magnetic fields in BLDC motors, improving power density without fundamentally changing the manufacturing process.
2Power
If conductors are arranged in complex shapes with more than three rectilinear segments, then the performance and power density of the machine is improved, but the design complexity and manufacturing difficulty increase
Solution Approach 1:
The patent leverages the universal capabilities of flexible PCB technology to implement complex conductor trajectories. The same PCB manufacturing processes that produce simple circuits can also produce complex multi-segment conductor patterns, allowing the winding to achieve optimized performance while maintaining ease of manufacture through standard industry techniques.
Solution Approach 2:
The patent uses the PCB trace copying capability to replicate complex conductor patterns precisely. By designing the conductor trajectory as a continuous curve or multiple segments on the PCB layout, the complex shape is accurately reproduced during manufacturing, achieving the desired performance without proportionally increasing manufacturing difficulty.
3Power
If variable width conductors are used to optimize torque constant and phase resistance ratio, then electrical efficiency is improved, but manufacturing precision requirements increase
Solution Approach 1:
The patent applies local quality by varying the conductor width at different positions along the PCB. This allows the winding to optimize the torque constant and phase resistance ratio by having wider conductors where higher current density is beneficial and narrower conductors where less current flows, thereby improving electrical efficiency while using standard PCB manufacturing capabilities.
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 approach results in a significant improvement in power density and electrical efficiency, with a 30% potential increase in power density and substantial gains in torque constant to phase resistance ratio, as demonstrated by varying the number of rectilinear segments and connection modes.
Implementation Method 1
The winding comprises a flexible PCB having a plurality of conductors on a first surface and a plurality of conductors on a second surface... adapted for inserting into said air gap... where the useful magnetic field of the magnets is radial
Data Source
Figure 1
Figure 2a~2b
Figure 3a~3b
AI summary
The invention provides a winding (40) for a rotating electrical machine (1) comprising a flexible PCB (45) having a plurality of conductors (60) on a first surface and a plurality of conductors (60) on a second surface, said conductors having a shape optimizing the performance of the machine, and a method for designing such a winding.