Bidirectional EV Charging Cable for Portable Grid Feed-Back
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing charging solutions for electric vehicles, such as wallboxes and emergency charging cables, require complex and expensive power electronics, significant installation effort, and are often inefficient, especially when dealing with lower power outputs and bidirectional energy transfer.
Innovation Solution
A portable single-phase charging cable with a lockable power plug and integrated bidirectional AC/DC and DC/DC converters, allowing for efficient charging and discharging of vehicle batteries, as well as feeding electrical power back into the grid, using a waterproof and dust-tight housing with communication interfaces for safe and efficient operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If wallboxes with three-phase connection are used for charging electric vehicles, then charging power is improved (11 kW to 22 kW), but device complexity and installation effort increase significantly
Solution Approach 1:
The patent divides the charging system into two separate functional components: a portable charging cable with AC/DC converter and a stationary wallbox with DC/DC converter and three-phase connection. This segmentation allows the complex three-phase functionality to be isolated in the wallbox while keeping the portable cable simple and versatile, resolving the contradiction between high power capability and device complexity.
Solution Approach 2:
The charging cable is designed with universal applicability to work with both single-phase household sockets and three-phase wallboxes. The cable includes bidirectional AC/DC and DC/DC converters that can operate in multiple modes (charging from AC, charging from DC, discharging to AC, discharging to DC), eliminating the need for different cables for different power sources and reducing overall system complexity.
2Power
If wallboxes with complex power electronics are deployed, then charging capacity is improved, but installation effort and costs increase
Solution Approach 1:
By segmenting the power electronics into separate modules (AC/DC converter in the portable cable, DC/DC converter in the wallbox), the patent reduces the installation complexity at each location. The portable cable with integrated AC/DC converter can be used anywhere without complex installation, while the wallbox only requires standard three-phase connection, significantly reducing overall installation effort compared to deploying full-featured wallboxes everywhere.
Solution Approach 2:
The portable charging cable is designed as a cost-effective, replaceable component that can be used with standard household sockets. This allows users to have multiple inexpensive portable cables rather than investing in expensive wallbox installations at every location, reducing the barrier to entry and making the system more accessible.
3Ease of operation
If emergency charging cables with unidirectional AC/DC converter are used, then portability is improved, but bidirectional energy transfer capability is lost
Solution Approach 1:
The charging cable is designed with bidirectional AC/DC and DC/DC converters that enable four operating modes: charging from AC mains, charging from DC vehicle battery, discharging vehicle battery to AC mains, and discharging to DC load. This multi-functionality maintains portability while adding V2G (vehicle-to-grid) and V2L (vehicle-to-load) capabilities, resolving the contradiction between simplicity and versatility.
Solution Approach 2:
The power converters in the charging cable are designed to dynamically switch between different operating modes based on the connection configuration and user needs. The bidirectional converters can adapt their function in real-time, allowing the same hardware to serve multiple purposes without requiring separate dedicated devices for each function.
4Loss of energy
If bidirectional converters are integrated into the charging cable, then energy transfer efficiency is improved, but device complexity increases
Solution Approach 1:
The patent merges the AC/DC converter and DC/DC converter into a single integrated charging cable unit with shared control electronics and housing. This consolidation reduces the overall system complexity compared to having separate devices for each conversion function, while maintaining the energy efficiency benefits of bidirectional conversion capabilities.
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 reduces installation effort and costs, enables efficient energy transfer with lower outputs, and provides a safe and efficient means to charge and discharge vehicle batteries while supporting the grid, with improved operational safety and utility of the vehicle battery.
Implementation Method 1
a single-phase charging cable for an electric vehicle, with a single-phase mains plug, a locking charging plug in the electric vehicle, and charging electronics electrically located between the mains plug and the charging plug, is additionally provided with a bidirectional AC/DC converter
Implementation Method 2
a single-phase charging cable for an electric vehicle, with a single-phase mains plug, a locking charging plug in the electric vehicle, and charging electronics electrically located between the mains plug and the charging plug, is additionally provided with a bidirectional AC/DC converter and at least one bidirectional DC/DC converter
Data Source
Figure 1~3
Figure 4~6
AI summary
The invention relates to a single-phase charging cable (1) for an electric vehicle (2), with a single-phase mains plug (4), with a charging plug (8) that can be locked in the electric vehicle (2) and with charging electronics (6) that are electrically arranged between the mains plug (4) and the charging plug (8), wherein the charging electronics (6) comprise a bidirectional AC/DC converter (10) and at least one bidirectional DC/DC converter (11, 12).