Three-Limb Transformer Winding Layout for Balanced Leakage Inductance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional three-winding planar transformers face challenges in integrating required leakage inductances for triple-active bridge (TAB) converters due to strong coupling between windings, which affects power transfer and zero-voltage-switching (ZVS) performance, especially at varying load conditions.
Innovation Solution
Three distinct winding structures are modeled and optimized to achieve balanced leakage and magnetizing inductances, including a central limb wound design, side limb wound design, and hybrid central and side limb wound uneven and interleaved winding configuration, considering frequency-dependent eddy currents and radial effects to minimize losses and maximize power density.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If conventional three-winding planar transformers are used with strong coupling between windings, then magnetizing inductance is maintained, but leakage inductance integration is difficult and power transfer capability deteriorates
Solution Approach 1:
The patent segments the windings into different groups positioned on opposite sides of the core, with each group having a specific number of turns configured to generate controlled leakage flux. This segmentation allows independent optimization of leakage inductance for each winding pair while maintaining overall transformer functionality.
Solution Approach 2:
The patent applies local quality by creating asymmetric winding configurations where different windings have different numbers of turns and positions. Specifically, the first and second windings have different turn ratios and are positioned differently relative to the core, creating localized variations in magnetic coupling that generate the required leakage inductance in specific regions while maintaining strong coupling elsewhere.
2Reliability
If leakage inductance is increased to improve zero-voltage-switching performance, then ZVS range is extended, but power transfer capability is reduced
Solution Approach 1:
The patent employs asymmetry by configuring windings with different numbers of turns and different positions on the core. The first winding has a different turn ratio than the second winding, and they are positioned on opposite sides of the core. This asymmetric configuration creates differential leakage flux that provides the necessary leakage inductance for ZVS while maintaining balanced power transfer characteristics.
Solution Approach 2:
The patent achieves dynamic performance by designing the transformer to adapt to varying load conditions. The specific winding configuration with unequal turns and opposite positioning creates a magnetic circuit that naturally adjusts the leakage inductance effect based on operating conditions, maintaining both ZVS capability and power transfer efficiency across a wide range of loads.
3Power
If asymmetric winding configurations are used to achieve desired leakage inductances, then power transfer capability is enhanced, but manufacturing precision requirements increase
Solution Approach 1:
The patent merges multiple functions into the transformer core structure itself. The core geometry and winding positions are integrated to simultaneously provide magnetic coupling, leakage inductance generation, and mechanical support. This merging reduces the need for separate adjustment mechanisms and simplifies manufacturing by making the leakage inductance an inherent property of the integrated structure rather than a separately tuned parameter.
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 optimized designs enhance power transfer capability and maintain robust control over a wide range of loads by achieving desired leakage inductances, reducing losses, and ensuring zero-voltage-switching across varying operational conditions.
Implementation Method 1
a first turn of the first winding encircles the central limb and the first outer limb
Implementation Method 2
a core, including: a central limb, a first outer limb, and a second outer limb
Data Source
AI summary
A transformer with leakage inductance. In some embodiments, a system includes: a transformer including: a core, including: a central limb, a first outer limb, and a second outer limb; a first winding; and a second winding, wherein a first turn of the first winding encircles the central limb and the first outer limb.