Switchable EV Charger Isolation for Safe, Efficient Power Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power systems for electric vehicles (EVs) lack efficient isolation mechanisms between utility grids and EV charging systems, leading to potential safety hazards and inefficiencies during charging and discharging processes.
Innovation Solution
Implementing switchable isolation components, including isolation transformers and energy storage devices with break-before-make connections, to selectively isolate or connect the utility grid and EV charging systems, using switches and converters to manage power flow efficiently.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If isolation components are continuously connected between utility grid and EV charging systems, then safety is improved, but component wear increases and system efficiency decreases
Solution Approach 1:
The isolation component's connection state is dynamically changed from static continuous connection to dynamic switchable connection. The system uses control circuitry to switch the isolation component between connected and disconnected states based on operational requirements, reducing unnecessary wear while maintaining safety when needed.
Solution Approach 2:
The system performs preliminary assessment of whether isolation is required before connecting the isolation component. The control circuitry evaluates system conditions and only connects the isolation component when actually needed, preventing unnecessary component wear and improving efficiency.
2Reliability
If isolation components are continuously connected between utility grid and EV charging systems, then safety is improved, but power transfer efficiency decreases
Solution Approach 1:
The connection state of the isolation component is dynamically adjusted based on real-time system conditions. When isolation is not required for safety, the component is disconnected, eliminating energy losses associated with continuous isolation and improving overall power transfer efficiency.
Solution Approach 2:
The control system performs preliminary evaluation of safety requirements before engaging the isolation component. This prevents unnecessary insertion of the isolation component into the power path, thereby avoiding energy losses and improving power transfer efficiency.
3Reliability
If isolation components are used during all charging operations, then safety is improved, but system complexity increases
Solution Approach 1:
The system implements dynamic control of the isolation component through switchable connections and control circuitry that assesses when isolation is actually required. This selective engagement reduces system complexity by avoiding permanent, unnecessary isolation infrastructure while maintaining safety when needed.
4Productivity
If switches are used to disconnect isolation component, then efficiency is improved, but risk of arcing and contact damage increases
Solution Approach 1:
An intermediary energy storage device (capacitor or inductor) is introduced between the switch and the isolation component. This intermediary absorbs transient energy during switching operations, preventing arcing and contact damage while allowing efficient disconnection when isolation is not required.
Solution Approach 2:
The energy storage device provides beforehand cushioning by being pre-charged or pre-configured to absorb potential transient energy during switching. This protective measure is in place before switching occurs, preventing arcing and contact damage while enabling efficient switchable connections.
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
Enhances safety and efficiency by allowing controlled power transfer between multiple sources and loads, reducing wear on components and increasing the lifetime of the circuit while ensuring safe charging and discharging operations.
Implementation Method 1
The isolation component may include an isolation transformer with H-bridges (electronic circuits that switch the polarity of voltages)
Implementation Method 2
An isolation component may include storage devices with switches configured in a break-before-make (BBM) connection to transfer energy in an isolated transition between two nodes
Implementation Method 3
an energy storage device (such as a battery, a capacitor, a super-capacitor, a fuel cell, a flywheel, etc.) may be used with the disclosed methods, circuits and the circuit components
Data Source
AI summary
One or more systems and methods for providing selective isolation between a grid and an electric vehicle (EV) during charging are disclosed. An isolation component may be located between input nodes, and one or more output nodes. The isolation component may be connected to the nodes by switches that select which one or more nodes is used to supply power for charging the EV battery. Other switches, such as relays, may bypass the isolation component when the grid is not connected. Further switches may isolate part of the system from the grid to connect the isolated power source to the EV, and in parallel connect the isolation component to the grid for combined power EV battery charging. The isolation component may comprise electrical energy storage devices with switches in series surrounding each device, where the switches may be operated in a break-before-make transition.