Galvanic Isolation via Resonant Capacitive Coupling
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Solution Overview
Problem
Existing solutions for galvanic isolation in power electronic applications, such as transformers, are complex, expensive, and space-intensive, making them inefficient for applications requiring galvanic isolation of control signals and energy transmission.
Innovation Solution
An AC voltage supply device that converts energy-supplying DC voltage into two galvanically isolated AC voltages using a semiconductor switch, inductive and capacitive resonance elements, and a feedback device, eliminating the need for transformers and inductive elements on the output side, and allowing for efficient galvanic isolation without parasitic capacitance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If transformers are used for galvanic isolation, then galvanic isolation of control signals is achieved, but device complexity and manufacturing cost increase
Solution Approach 1:
The patent extracts the galvanic isolation function from the traditional transformer structure by removing the magnetic core and windings, retaining only the essential electromagnetic coupling capability through capacitive and inductive resonance elements. This eliminates the complex manufacturing processes while preserving the isolation function.
Solution Approach 2:
The patent replaces the mechanical/magnetic transformer structure with an electrical resonance-based system using capacitive and inductive elements. This substitution eliminates the need for magnetic cores and complex winding structures, significantly reducing device complexity while maintaining galvanic isolation.
2Reliability
If transformers are used for galvanic isolation, then galvanic isolation of control signals is achieved, but manufacturing cost increases
Solution Approach 1:
The patent employs simple, inexpensive capacitive and inductive resonance elements that can be manufactured using standard PCB techniques and surface-mount components, replacing expensive transformer assemblies. These elements are cost-effective and can be easily integrated into circuit boards.
Solution Approach 2:
By replacing the mechanical transformer structure with electrical resonance circuits, the patent enables manufacturing through standard electronic fabrication processes, significantly reducing production costs while maintaining isolation performance.
3Reliability
If transformers are used for galvanic isolation, then galvanic isolation is achieved, but space consumption increases
Solution Approach 1:
The patent extracts only the essential electromagnetic coupling function from the transformer, eliminating the bulky magnetic core and thick windings. The remaining capacitive and inductive elements occupy minimal space, suitable for compact electronic designs.
Solution Approach 2:
Replacing the physical transformer with electrical resonance elements dramatically reduces the space required for galvanic isolation, allowing integration into compact circuits and portable devices.
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 provides improved electrical isolation without the complexity and cost of transformers, enabling efficient and compact galvanic isolation of AC voltages, which can be further extended to generate multiple isolated AC or DC voltages.
Implementation Method 1
an inductive input element electrically connecting the first voltage input and the first switch contact; an inductive resonance element, which electrically connects the first switching contact to a first contact of a first capacitive resonance element
Implementation Method 2
a first capacitive resonance element of the AC voltage supply device, assigned to the first AC voltage, with a first contact; a second capacitive resonance element of the AC voltage supply device, which second capacitive resonance element is assigned to the first AC voltage and has a first contact
Implementation Method 3
with an inductive connection element which electrically connects the third voltage input and the control contact, and with a parasitic capacitance which connects the first switching contact with the control contact
Data Source
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AI summary
The invention relates to: an AC power supply device for converting an energy-supplying DC voltage into a first AC voltage and into a second AC voltage galvanically isolated from the first AC voltage; a DC power supply device for converting an energy-supplying DC voltage into a first DC voltage and into a second DC voltage galvanically isolated from the first DC voltage; a driver circuit for controlling a first power semiconductor and a second power semiconductor; and a power semiconductor circuit comprising a first power semiconductor, a second power semiconductor and a driver circuit.