Battery Stack Arc Fault Detection With Node Isolation Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing battery management systems lack the capability to identify and extinguish arc faults, which can lead to safety issues and system failures due to short circuit voltages and currents being transferred between batteries.
Innovation Solution
A hierarchical arc fault monitoring method is implemented in an energy storage system, which involves obtaining electrical measurement values for each stack and the system as a whole, determining the absence of arc faults within and outside the stacks, and isolating affected batteries to prevent further damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If battery cells are arranged in series to achieve required operating voltage, then system voltage is improved, but arc faults can occur between nodes causing safety issues
Solution Approach 1:
The system performs preliminary arc fault detection by continuously monitoring voltage measurements from battery management system nodes before arc faults can cause damage. The hierarchical detection approach identifies potential arc conditions early by comparing expected voltage sums with actual measurements, enabling preventive action before hazardous arc faults develop in high-voltage series configurations.
Solution Approach 2:
The system implements feedback mechanisms where voltage measurement data from individual stacks is fed back to the control system, which compares these measurements against system-level voltage measurements. This feedback loop enables real-time detection of voltage anomalies indicating arc faults, allowing the system to respond to and mitigate arc risks in series-connected battery configurations.
2Reliability
If a hierarchical arc fault monitoring method is implemented, then arc fault detection capability is improved, but system complexity increases due to multiple measurement and determination steps
Solution Approach 1:
The system uses universal voltage measurement capabilities that already exist in battery management system nodes for multiple purposes: standard battery monitoring and the new arc fault detection function. By leveraging existing voltage measurement infrastructure for dual purposes, the system achieves comprehensive arc fault detection without proportionally increasing hardware complexity, as the same measurement circuits serve both traditional and arc detection functions.
Data Source
AI summary
A battery stack includes a plurality of battery management system (BMS) nodes and a controller. Each BMS node includes a battery, an isolation switch configured to selectably isolate the battery of the BMS node from the batteries of the other BMS nodes, and a bypass switch configured to selectably provide a path for electrical current flowing through the battery stack to bypass the battery of the BMS node. The batteries of the BMS nodes are electrically coupled in series. The controller is configured to control the isolation switch and the bypass switch of each BMS node such that the battery of each BMS node can be individually connected to and disconnected from an electrical power source/sink.