Variable Flux Bridge for Electric Machine Rotor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electric machines in electrified vehicles face challenges in achieving high power outputs and efficient thermal management due to limitations in the interaction between stator cores and rotors, leading to suboptimal power efficiency and increased stator core losses.
Innovation Solution
The electric machine assembly incorporates a sliding bridge within the rotor's channel, adjustable by a spring and non-magnetic guides, to control magnetic flux paths and optimize torque output by varying the bridge's position based on rotor speed and geometry, thereby enhancing magnetic flux utilization and reducing stator core losses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a fixed magnetic flux path is used between rotor and stator, then the structure is simple, but power efficiency is suboptimal and stator core losses increase
Solution Approach 1:
The patent applies the dynamics principle by introducing a movable bridge component within the rotor that can dynamically adjust its position along the magnetic flux path. This movable bridge allows the magnetic circuit to adapt its configuration in response to varying operating conditions, thereby optimizing magnetic flux distribution and reducing stator core losses without requiring a completely complex rotor structure
Solution Approach 2:
The patent implements parameter changes by varying the effective magnetic path length and flux distribution through the adjustable bridge position. By changing the geometric parameters of the magnetic circuit (bridge position, air gap dimensions), the system optimizes magnetic flux density distribution to minimize core losses while maintaining structural feasibility
2Power
If higher power outputs are achieved, then drive range is extended, but thermal management capacity requirements increase
Solution Approach 1:
The adjustable bridge mechanism enables dynamic parameter changes in the magnetic circuit that optimize power conversion efficiency across different operating conditions. By improving electromagnetic coupling and reducing magnetic losses, the system achieves higher effective power output while minimizing heat generation, thereby reducing thermal management requirements
3Loss of energy
If magnetic flux utilization is improved, then power efficiency increases, but control complexity increases
Solution Approach 1:
The movable bridge creates a dynamic magnetic circuit that automatically adapts to operating conditions, improving magnetic flux utilization and power efficiency. The mechanical adjustability provides inherent control through position-dependent magnetic coupling, achieving efficient flux management without requiring complex electronic control systems
Solution Approach 2:
The bridge mechanism can be designed to self-adjust based on centrifugal forces or spring mechanisms that respond naturally to operating conditions, enabling automatic optimization of magnetic flux paths without external control intervention, thereby improving efficiency while minimizing control 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 solution allows for improved torque output and efficiency across varying drive cycles by dynamically adjusting magnetic flux, reducing stator core losses and enhancing overall power management in electric machines.
Implementation Method 1
The translation of the bridge adjusts a path of magnetic flux from the rotor to the stator core based on the bridge position
Implementation Method 2
a spring disposed within the channel and oriented to bias movement of the bridge toward a direction opposite a centrifugal force direction created by rotation of the rotor
Implementation Method 3
The spring may be tuned to optimize bridge position within the channel based on rotor torque speed specifications and rotor geometry
Implementation Method 4
The non-magnetic guides may be of a material having low friction coefficient characteristics to assist in facilitating translation of the bridge within the channel
Data Source
AI summary
A vehicle electric machine assembly including a stator core, a rotor, and a bridge is provided. The stator core defines a cavity. The rotor is disposed within the cavity and may include a channel defined between two magnets. The bridge is disposed within the channel for translation between at least a first and a second position. The translation of the bridge adjusts a path of magnetic flux from the rotor to the stator core based on the bridge position. The bridge may be of a ferromagnetic material. The assembly may further include a first non-magnetic guide mounted on a first side of the channel at a substantially central channel region and a second magnetic guide mounted on a second side of the channel at the substantially central channel region.