Nested Bobbin Transformer Layout for Low Parasitic Capacitance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing transformer modules face challenges in minimizing parasitic capacitance and noise generation while maintaining compact size and high power conversion efficiency, particularly in electric vehicles where electromagnetic interference can cause malfunctions.

Innovation Solution

A transformer module design featuring a first bobbin unit for the primary coil and a second bobbin unit for the secondary coil, with specific side plates and partition units to minimize overlap and parasitic capacitance, and a core unit to guide and protect the coils, ensuring stable winding and efficient power conversion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-generated harmful factors

If the primary coil and secondary coil areas are made to overlap partially to decrease parasitic capacitance, then parasitic capacitance is reduced and noise is minimized, but the winding stability and power conversion efficiency may be compromised

Engineering Contradiction:
Improveparasitic capacitanceVSAvoidwinding stability
Core Design Contradiction:
Object-generated harmful factorsVSReliability

Solution Approach 1:

The transformer is divided into separate first and second bobbin units, each housing one coil. This segmentation allows the coils to be positioned with partial overlap of their wound areas, reducing parasitic capacitance while maintaining independent winding structures for stability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The first bobbin unit is accommodated within the second bobbin unit, creating a nested configuration. This nesting enables the primary and secondary coil areas to partially overlap, achieving reduced parasitic capacitance while the containing bobbin structure maintains winding stability.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Object-generated harmful factors

If the primary coil and secondary coil areas are made to overlap partially to decrease parasitic capacitance, then parasitic capacitance is reduced and noise is minimized, but the power conversion efficiency may be compromised

Engineering Contradiction:
ImprovenoiseVSAvoidpower conversion efficiency
Core Design Contradiction:
Object-generated harmful factorsVSLoss of energy

Solution Approach 1:

Separating the coils into distinct bobbin units with controlled spatial overlap reduces electromagnetic interference and noise while maintaining efficient magnetic coupling for power conversion.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The bobbin units serve as intermediary structures that enable optimal positioning of the coils. The partial overlap configuration mediated by the bobbins reduces noise through decreased parasitic capacitance while preserving power conversion efficiency.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Area of stationary object

If a compact transformer structure is implemented to minimize the area occupied, then the transformer module size is reduced, but the winding stability and manufacturing complexity may increase

Engineering Contradiction:
Improvetransformer module areaVSAvoidwinding stability
Core Design Contradiction:
Area of stationary objectVSEase of manufacture

Solution Approach 1:

The nested configuration of the first bobbin unit within the second bobbin unit achieves a compact transformer module that minimizes occupied area while the structured nesting provides inherent support for stable winding and assembly.

Inventive Principle:
Principle #7Nested doll (Nesting)

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 effectively reduces parasitic capacitance and noise, enhancing electrical stability and power conversion efficiency while maintaining a compact form factor suitable for high-voltage applications.

Implementation Method 1

a transformer module includes a first bobbin unit around which a primary coil is wound and a second bobbin unit around which a secondary coil is wound

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentEP4607549A1Transformer module
Publication Date: 2025.08.27 HYUNDAI MOBIS CO LTD
  • EP4607549A1 patent drawingFigure 1
  • EP4607549A1 patent drawingFigure 2
  • EP4607549A1 patent drawingFigure 3

AI summary

A transformer module may include a first bobbin unit around which a primary coil is wound and a second bobbin unit around which a secondary coil is wound and that accommodates at least a portion of the first bobbin unit.