EV Battery Fault Tolerance via Dual Control Units
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current electric vehicle battery systems lack sufficient fault tolerance, leading to potential breakdowns if control or supervision units fail, requiring costly redundancy that increases weight and space, and fail to distinguish between defects in battery cells, modules, or sensor systems effectively.
Innovation Solution
A battery system with redundant master and slave control units and supervision units, each equipped with identical hardware and software, where measured values from sensors are constantly compared to detect deviations, allowing for clear identification of defects and enabling the system to switch to redundant components if necessary, without requiring redundant battery modules.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If redundant battery modules and supervision units are duplicated to achieve fault tolerance, then reliability is improved, but device complexity, weight, and cost increase
Solution Approach 1:
The system dynamically assigns master and slave roles to control units based on operational status. The slave control unit continuously monitors and can take over master functions if the master fails, creating a dynamic fault-tolerant system without duplicating the entire battery module structure. This dynamic role assignment resolves the contradiction by achieving reliability through flexible functionality rather than static redundancy.
Solution Approach 2:
The slave control unit creates a functional copy of the master control unit's monitoring and control capabilities. Instead of duplicating entire battery modules, the system copies the essential control functions into a slave unit that can assume master responsibilities. This copying approach provides fault tolerance while minimizing the increase in device complexity compared to full duplication.
2Measurement precision
If redundant control units and sensors are added to distinguish defects, then measurement precision is improved, but weight and space increase
Solution Approach 1:
The slave control unit serves multiple functions: it monitors battery parameters independently, validates measurements from the master control unit, and can take over master functions if needed. This multi-functionality allows the system to achieve improved defect detection accuracy without adding proportionally more weight, as one control unit performs multiple critical roles.
Solution Approach 2:
The redundant control units and sensors perform self-diagnosis by comparing their measurements against each other. The system uses its own internal resources (the slave unit monitoring the master unit and vice versa) to detect defects, eliminating the need for additional external diagnostic equipment that would increase weight and space.
3Reliability
If full redundancy of all sub-components is implemented, then reliability is improved, but cost increases
Solution Approach 1:
Instead of implementing full redundancy of all battery components, the system applies partial redundancy only to the control units and their associated sensors. This selective approach provides sufficient fault tolerance for the critical control functions while avoiding the excessive cost of duplicating entire battery modules. The partial redundancy strategy achieves an optimal balance between reliability and manufacturing cost.
Data Source
AI summary
A battery system for an electric vehicle. The electric vehicle includes a plurality of serially interconnected battery modules, each battery module having at least two battery cells interconnected in parallel, a master control unit for supervising the battery modules, and a slave control unit for supervising the battery modules. A master supervision unit having master sensors for detecting measured values of the battery cells and of the battery module and a slave supervision unit having slave sensors for detecting measured values of the battery cells and of the battery module are assigned to each battery module. The master supervision units communicate with the master control unit, the slave supervision units communicate with the slave control unit, and the master control unit communicates with the slave control unit.