Contactor Off-Prevention Circuit With Multi-Terminal Redundancy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing contactor systems in electric vehicles are prone to unnecessary power off due to simple abnormalities in positive or negative electrode terminals, leading to potential vehicle stoppages and safety risks, as they rely on single connectors for power supply and lack effective overcurrent protection.
Innovation Solution
A circuit design that multi-connects battery management systems and contactors via multiple positive and negative electrode terminals, using fuses or switches to manage overcurrents and maintain power supply through alternative connections, even if one connector fails, and employs diodes to determine current direction and a coil to control the contactor's on/off state.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If single connector is used for connecting BMS and contactor, then device complexity is reduced, but reliability deteriorates due to unnecessary power off when terminal abnormality occurs
Solution Approach 1:
The single connector is segmented into multiple independent connection paths (first positive electrode terminal, second positive electrode terminal, first negative electrode terminal, second negative electrode terminal). Each terminal can independently conduct power, so when one terminal experiences abnormality, power can still flow through other terminals, preventing unnecessary contactor power off and improving system reliability.
2Object-affected harmful factors
If overcurrent protection is not implemented, then device complexity is reduced, but harmful factors increase due to external short-circuit damage
Solution Approach 1:
Overcurrent protection devices (fuses or switches) are pre-installed in each connection path between BMS and contactor. These protection elements are configured in advance to detect and respond to overcurrent conditions. When external short-circuit or abnormal overcurrent occurs, the protection devices automatically activate to block excessive current, preventing damage to the battery management system and other components before damage can occur.
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
This design ensures continuous power supply to the contactor by utilizing multiple connections and overcurrent protection, preventing unnecessary power off and reducing the risk of vehicle stoppages due to terminal abnormalities or external short-circuits.
Implementation Method 1
the contactor is mainly configured to connect the battery pack and the load based on a magnetic field when a coil provided in the contactor receives a voltage via a BMS and generates the magnetic field
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention relates to a circuit for preventing power off of a contactor, in which a battery management system and a contactor are multi-connected via a plurality of positive electrode terminals and a plurality of negative electrode terminals provided in each of the battery management system and the contactor, so that even when any one connection among the connections of the plurality of positive electrode terminals and the plurality of negative electrode terminals is disconnected or opened, it is possible to maintain supply of power supplied from the battery management system to the contactor through another connection of the positive electrode terminal and the negative electrode terminal.