Adaptive Isolation Fault Testing for Multi-String EV Batteries
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Managing power sources in electric vehicles is challenging due to difficulties in balancing power, efficiency, and reliability, as battery packs can suffer from internal or external failures that affect their ability to support critical loads or provide sufficient current.
Innovation Solution
An adaptive and adjustable isolation fault testing system for multi-string batteries in electric vehicles, where a battery management circuit selectively controls switches to perform isolation fault tests on individual battery strings within dedicated time windows, allowing for timely identification and management of internal or external faults.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If isolation fault testing is performed on battery strings, then reliability is improved, but device complexity increases due to additional switches and control circuits
Solution Approach 1:
The battery pack is divided into multiple independent battery strings, each with its own switch (first switch, second switch, etc.). The battery management circuit can selectively control each switch independently to perform isolation fault testing on individual battery strings, allowing fault detection without testing the entire battery pack as a single unit.
Solution Approach 2:
The battery management circuit performs isolation fault testing on battery strings during dedicated time windows before faults can affect critical loads. By proactively testing battery strings in advance and identifying potential failures early, the system ensures reliability without requiring complex real-time fault detection during critical operation.
2Measurement precision
If isolation fault testing is performed on all battery strings, then measurement precision is improved, but loss of time increases due to sequential testing requirements
Solution Approach 1:
The battery management circuit implements periodic isolation fault testing by allocating dedicated time windows for testing different battery strings. Instead of continuous testing that would cause time loss, the system periodically cycles through testing each battery string in sequence, achieving comprehensive fault detection while minimizing time impact on vehicle operation.
Solution Approach 2:
The testing process is segmented into separate time windows for different battery strings. The battery management circuit tests the first battery string in one time window, then tests the second battery string in another time window, allowing parallel time management that reduces total testing duration while maintaining precise fault localization capability for each string.
3Ease of operation
If battery strings are disconnected for testing, then ease of operation is improved, but productivity decreases due to testing interruptions
Solution Approach 1:
The battery pack is segmented into multiple battery strings with individual switches, allowing the battery management circuit to disconnect and test only the specific battery string under investigation while keeping other battery strings connected and operational. This segmentation enables isolated testing without requiring complete system shutdown.
Solution Approach 2:
Multiple battery strings are merged into a single battery pack system that can operate collectively. When one battery string is disconnected for testing, the other battery strings remain connected and continue to supply power to critical loads, combining the operational capacity of multiple strings to maintain productivity during testing operations.
Data Source
AI summary
An adaptive and adjustable isolation fault testing of a multi-string battery of an electric vehicle is disclosed. The isolation fault testing can be performed in an adjustable or predetermined loop having dedicated time windows for respective battery strings in compliance with the system requirements, specification, and regulatory regime.