Galvanically Isolated Charging Interface for Marine Corrosion Control
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Solution Overview
Problem
Charging systems for marine vessels face issues with corrosion due to stray currents generated when the vessel's metallic hull is grounded to water and connected to an onshore charging station, causing conventional corrosion protection arrangements to prevent the charging process from starting.
Innovation Solution
A communication interface that galvanically isolates the charging control circuit from the charging station, using an input circuitry to maintain equivalent input characteristics between the charging control circuit and an interface circuit, ensuring the charging control unit receives the correct signals while preventing stray currents.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the vessel's hull is grounded to water and connected to an onshore charging station, then charging operation is enabled, but stray currents are generated causing corrosion
Solution Approach 1:
An isolation transformer is introduced as an intermediary device between the charging station and the vessel's charging control circuit. The transformer provides galvanic isolation, blocking the direct electrical connection that causes stray currents and corrosion, while still enabling bidirectional communication for charging control through its windings.
Solution Approach 2:
The patent replaces direct electrical connection (mechanical/electrical contact) with magnetic coupling through the isolation transformer. This substitution eliminates the galvanic path for stray currents while maintaining the functional connection needed for charging operations and communication.
2Object-affected harmful factors
If conventional corrosion protection arrangements are used, then corrosion is prevented, but the charging process cannot start
Solution Approach 1:
The isolation transformer acts as a mediator that allows the charging control circuit to communicate with the charging station without creating a galvanic connection. This enables the charging process to start and proceed while the vessel's existing corrosion protection arrangements remain intact and effective.
3Object-affected harmful factors
If galvanic isolation is implemented, then stray currents are blocked, but communication between charging control circuit and charging station is disrupted
Solution Approach 1:
The patent substitutes direct electrical signal transmission with magnetic coupling through the isolation transformer. Control signals from the charging station can be transmitted to the charging control circuit and responses can be sent back through the transformer's windings, maintaining communication while blocking galvanic connections and stray currents.
Solution Approach 2:
The isolation transformer serves as an intermediary that transfers electrical signals between isolated circuits through magnetic induction. This allows bidirectional communication for charging control while preventing the formation of galvanic loops that cause corrosion.
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
Enables charging of marine vessels with conventional corrosion protection arrangements by maintaining signal integrity and preventing corrosion, allowing the charging process to proceed without modifying existing protection systems.
Implementation Method 1
an interface circuit (12) configured to assume an interface circuit input characteristic (Va) when connected to the charging station (3'), the interface circuit (12) being galvanically isolated from the charging control circuit (18)
Data Source
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AI summary
A communications interface (1) communication interface (1) for a charging system (3), said communication interface (1) being electrically connectable to a charging station (3'), said communication interface (1) comprising a charging control circuit (18) configured to assume a charging control circuit input characteristic (V'a) when receiving a charging control circuit input (V'0), said charging control circuit (18) being configured to communicate with a charging control unit (22) of said charging system (3); an interface circuit (12) configured to assume an interface circuit input characteristic (Va) when connected to said charging station (3'), said interface circuit (12) being galvanically isolated from said charging control circuit (18), and an input circuitry (14) configured to receive at least information indicative of said interface circuit input characteristic (Va) from said interface circuit (12) or said charging control circuit (18) when said interface circuit (12) is connected to said charging station (3'), said input circuitry (14) being configured to control an input on said charging control circuit (18) or said interface circuit (12) resulting in that a ratio between said interface circuit input characteristic (Va) and said charging control circuit input characteristic (V'a) is within a predetermined range, preferably the predetermined range is at least 80% - 120%, more preferred at least 90% - 110%.