Mode 2 Charging Cable Galvanic Protection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing mode 2 charging cords for electric and hybrid vehicles face issues with high costs, safety risks, and interference with differential protection due to complex wiring arrangements, which can lead to electrical fires and increased charging times.

Innovation Solution

A charging cord design featuring a second control wire coupled with galvanic protection means that isolate the control circuit from the phase and neutral wires, preventing direct current flow and simplifying protection mechanisms, while using opto-couplers or transformers to warn the control means of the circuit state, and incorporating auxiliary protection components like resistive and capacitive components to ensure safety.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If two different sub-parts of the electric cable are used for control wires, then the control function is achieved, but the cost increases and safety risks arise

Engineering Contradiction:
Improvecontrol functionVSAvoidcable structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies homogeneity by using two identical cable sub-parts instead of different types. Both sub-parts contain the same configuration of wires (phase, neutral, earth, and control wires), making them interchangeable and simplifying the overall cable structure while maintaining control functionality.

Inventive Principle:
Principle #33Homogeneity

Solution Approach 2:

The identical cable sub-parts serve multiple functions: they provide both power transmission and control signals simultaneously. Each sub-part is designed to handle all necessary electrical connections, eliminating the need for specialized different cable types.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Ease of operation

If control wires are directly connected to phase and neutral wires, then the control circuit functions, but safety risks increase due to potential contact and electrical fires

Engineering Contradiction:
Improvecontrol circuit operationVSAvoidelectrical fire risk
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The patent introduces an optical coupler as an intermediary device between the control circuit and the power circuit. The optical coupler receives control signals and transmits them optically to the other side of the isolation barrier, preventing direct electrical contact between control wires and power wires while maintaining control functionality.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces the direct electrical (mechanical) connection between control and power circuits with an optical transmission system. The optical coupler converts electrical signals to optical signals and back, eliminating the need for direct wire-to-wire contact and thereby preventing electrical fire risks.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Productivity

If current flows in the electric circuit for charging, then charging function is achieved, but differential protection means are disturbed causing edge effects

Engineering Contradiction:
Improvecharging speedVSAvoidprotection mechanism
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The optical coupler acts as an intermediary that isolates the control circuit from the power circuit. This isolation prevents charging current from flowing into the control circuit and interfering with differential protection means, while still allowing control signals to be transmitted effectively for maintaining charging functionality.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Object-affected harmful factors

If complex wiring arrangements are used for galvanic protection, then safety is improved, but cost and complexity increase

Engineering Contradiction:
Improveelectrical safetyVSAvoidwiring arrangement
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The optical coupler provides galvanic isolation in a single integrated component, replacing what would otherwise require complex multi-wire isolation arrangements. This approach maintains electrical safety by preventing current flow between circuits while simplifying the wiring structure.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent extracts the galvanic isolation function from the wiring arrangement itself and places it in a dedicated optical coupler component. This separation allows the wiring to remain simple while the isolation function is performed by the specialized optical device.

Inventive Principle:
Principle #2Taking out (Extraction)

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 design reduces costs by using two identical cable sub-parts, enhances safety by preventing electrical fires, and minimizes interference with differential protection, allowing for efficient and safe charging without disturbing the control box's protection mechanisms.

Implementation Method 1

The galvanic protection means may comprise an optical coupler capable, in the event of a current flowing in the electric circuit, of generating another current intended to warn the control means of the placement of the electric circuit in its first state

Methodology Applied
Scientific EffectOpto-coupling: Photoelectric Effect

Implementation Method 2

the galvanic protection means can comprise a transformer having primary and secondary windings. In this case, the secondary winding is capable of generating a current which is intended to warn the control means of the placement of the electric circuit in its first state in the event of circulation in the primary winding of a current which comes from the electric circuit

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 3

Generally the second means of action of the power outlet are in the form of a magnet intended to act on the first means of action of a charging cord, which are in the form of at least one switch magnetic blade

Methodology Applied
Scientific EffectMagnetic interaction: Magnetism

Data Source

PatentEP2786451B1Mode 2 charging cable with galvanic protection means for a vehicle
Publication Date: 2017.11.15 PSA AUTOMOBILES SA
  • EP2786451B1 patent drawingFigure 1~2
  • EP2786451B1 patent drawingFigure 3~4

AI summary

A charging cable (CC) comprising i) a first plug (P1) capable of being connected to an electrical socket and comprising first operating means (L) specific to placing an electrical circuit in a first state in the event of cooperation with second operating means of the electrical socket, ii) a second plug (P2) capable of being connected to a socket in a vehicle, iii) an electrical cable (CA) comprising at least neutral wires (FN) and live wires (FP) interconnecting the first (P1) and second (P2) plugs, and iv) a control unit (BC) comprising control means (MC) coupled with the electrical circuit and arranged to send a signal to a first control wire (FC1), connected to the second plug (P2), when the electrical circuit is in its first state. The electrical circuit comprises a second control wire (FC2) coupled with the first operating means (L), a first connection connecting the first operating means (L) to either the neutral wire (FN) or the live wire (FP), a second connection connected to the remaining neutral wire (FN) or live wire (FP), and galvanic protection means (MP) connected to the second control wire (FC2) and to the second connection and arranged to provide galvanic protection of the control means (MC) in relation to the neutral wire (FN), the live wire (FP) and the second control wire (FC2), and for warning the control means (MC) when the electrical circuit is in its first state. (Figure 1)