Battery Pack Switch Retention Control for Fault-Safe Operation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing switch control devices in battery packs for environmentally-friendly vehicles may lose driving force and cause accidents when the control device malfunctions, and the retention circuit designed to maintain the switch state can also cause malfunctions due to aging or unknown issues.
Innovation Solution
A switch control device that includes a retention circuit configured to receive control and safety signals, a retention control circuit to enable/disable the retention function, and a driver to control the switch based on these signals, allowing the retention circuit to maintain the switch state only during predetermined times or when necessary, preventing unwanted malfunctions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a retention circuit is added to maintain switch state during control device malfunction, then vehicle safety is improved, but device complexity increases and potential malfunction sources increase
Solution Approach 1:
The control system is segmented into two independent controllers: a first controller for normal operation and a second controller for safety monitoring. The retention circuit is controlled by the first controller but monitored by the second controller, creating modular functional segments that reduce overall system complexity while maintaining safety
Solution Approach 2:
The second controller acts as an intermediary safety monitor that supervises the first controller's operation and the retention circuit's behavior. This intermediary layer provides safety verification without requiring complete redesign of the retention circuit architecture
2Reliability
If a retention circuit is always enabled to maintain switch state, then control reliability is improved, but risk of unwanted malfunctions due to aging or unknown issues increases
Solution Approach 1:
The retention circuit operation is made periodic rather than continuous - it is enabled only when the second controller detects a malfunction condition and disables it after a predetermined time period. This periodic activation reduces the window of opportunity for unwanted malfunctions while maintaining safety during critical failure conditions
Solution Approach 2:
The retention circuit's operational state is made dynamic rather than static. The circuit transitions between enabled and disabled states based on real-time monitoring by the second controller, allowing the system to adapt to changing conditions and reduce risk during normal operation while providing protection during actual malfunctions
Data Source
Figure 1
Figure 2
Figure 3A
AI summary
A switch control device according to the present disclosure may include a retention circuit configured to receive a control signal and a safety signal, and to output a retention signal to the driver of the switch to maintain the on state of the switch based on the control signal and the safety signal; a retention control circuit configured to disable the retention circuit, so that the output of the retention signal is blocked when a disable signal is received; a first controller configured to output the control signal to the driver to control the operation of the switch, and to output the disable signal to the retention control circuit when the retention circuit is set to be disabled in a system to which the switch control device is mounted; and a second controller configured to output the safety signal according to the operation status of the first controller. The driver is configured to control the opening/closing of the switch based on the control signal or the retention signal.