Planar Isolated Coupling Structure for AC-DC Converters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing AC-DC converter systems require a high-cost, large-package pulse transformer or unreliable coupling capacitors for fast isolation between controllers, which are not cost-effective and stable enough for precise voltage and current regulation.
Innovation Solution
An isolated coupling structure using a first and second coupling coil with mutual inductance, where the second coil is electrically connected to both controllers, and the first coil is connected to the primary and secondary sides, achieving signal transmission with fast isolation and reduced package dimensions through a dielectric layer with specific design features like through vias and FR-4 material for high voltage withstand.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a pulse transformer is used for fast isolation between controllers, then signal transmission reliability is improved, but cost and package dimensions increase
Solution Approach 1:
The patent uses planar coils formed on PCB boards as a simplified copy of traditional pulse transformer windings. The first coil is formed on the primary side PCB and the second coil on the secondary side PCB, eliminating the need for a separate pulse transformer component while maintaining the essential magnetic coupling function through mutual inductance.
Solution Approach 2:
The patent merges the coupling element function with the existing PCB structures by forming coils directly on the PCB boards. The PCB board itself serves as the support structure for the coils, integrating what would traditionally be separate components (transformer windings and PCB) into a unified structure that reduces overall package size.
2Reliability
If a pulse transformer is used for fast isolation between controllers, then signal transmission reliability is improved, but device cost increases
Solution Approach 1:
The patent uses planar coils formed on PCB boards as a simplified copy of traditional pulse transformer windings. The first coil is formed on the primary side PCB and the second coil on the secondary side PCB, eliminating the need for a separate pulse transformer component while maintaining the essential magnetic coupling function through mutual inductance.
Solution Approach 2:
The patent replaces the expensive pulse transformer with a cost-effective PCB-based coil structure. The coils are formed using standard PCB fabrication processes, making the coupling element inexpensive to manufacture while sufficient for the application's signal transmission needs.
3Area of stationary object
If coupling capacitors are used for signal transmission, then package dimensions are reduced, but reliability deteriorates
Solution Approach 1:
The patent replaces the electrical coupling capacitor with a magnetic coupling system using coils and mutual inductance. This substitution provides galvanic isolation similar to transformers while maintaining compact dimensions, achieving both size reduction and reliability requirements through electromagnetic induction rather than direct electrical connection.
4Productivity
If traditional coupling elements are used, then signal transmission is achieved, but data integrity deteriorates
Solution Approach 1:
The patent introduces a dielectric layer as an intermediary between the first and second coils. This dielectric layer provides electrical isolation while allowing magnetic field coupling, ensuring clean signal transmission without direct electrical contact that could introduce noise or interference, thereby maintaining data integrity.
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 solution provides a low-cost, compact, and reliable coupling element with improved data integrity and device reliability, enabling precise voltage and current regulation in AC-DC converters by using a dielectric layer with planar coils and specific design features for high voltage and humidity resistance.
Implementation Method 1
The second coupling coil is configured to create a mutual inductance with the first coupling coil
Implementation Method 2
A first dielectric layer comprises a first face and a second face opposite to the first face
Data Source
AI summary
An isolation coupling structure for transmitting a feedback signal between a secondary side and a primary side of a voltage conversion device includes a first dielectric layer including a first face and a second face opposite to the first face, a first coupling coil disposed on the first face enclosing to form an inner region; a second coupling coil configured to couple with the first coupling coil. The second coupling coil includes a first coil portion and a second coil portion, where the first coil portion is disposed on the second face, the second coil portion is disposed on the first face and located inside the inner region. The second coil portion is isolated from the first coupling coil, and the first coil portion and the second coil portion are electrically connected. The technical effect is that it can realize the electrical isolation and the coupling with low cost and small package size.