Vehicle Power Shut-Off Control for Early Abnormal Current Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle control systems using semiconductor fuses face challenges with increased MOS transistor size and complexity, high-temperature breakdowns, and the need for early detection of abnormal currents, leading to increased costs and space requirements.
Innovation Solution
A vehicle control device incorporating a shut-off unit, current detector, and temperature detector that dynamically adjusts shut-off thresholds based on priority rankings and temperature to prevent abnormal currents, using semiconductor switches to manage power distribution to multiple load devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the current capacity of the MOS transistor is increased to handle more actuators, then the power supply capability is improved, but the transistor size and mounting area increase
Solution Approach 1:
The patent divides the power supply system into multiple independent power supply units, each handling a subset of actuators. This segmentation allows each MOS transistor to be sized appropriately for its specific load rather than requiring one oversized transistor for all actuators, thereby reducing the mounting area while maintaining adequate current capacity for each segment.
2Temperature
If the MOS transistor is made multi-parallel to secure heat dissipation, then the thermal management is improved, but the device complexity and mounting area increase
Solution Approach 1:
By segmenting the power supply into multiple units with individual MOS transistors, each transistor handles a manageable current load, naturally reducing the heat generation per device. This eliminates the need for complex multi-parallel configurations while achieving adequate heat dissipation through proper thermal design of each segmented unit.
3Reliability
If conventional fusion fuses are used, then the power shut-off function is provided, but the fuse needs to be replaced when fused, requiring easy user access
Solution Approach 1:
The patent replaces the mechanical fusion fuse with an electronic control system using MOS transistors that can be controlled to shut off power supply. This electronic replacement eliminates the need for physical fuse replacement while maintaining the power protection function, as the control device can open the MOS transistor to cut power when abnormalities are detected.
4Reliability
If the ECU is firmly fastened to protect electronic components, then the reliability is improved, but the fuse or relay replacement becomes difficult
Solution Approach 1:
By replacing the mechanical fuse with an electronically controllable MOS transistor integrated into the ECU, the system maintains reliable component protection through the firmly fastened ECU while eliminating the need for physical fuse replacement. The electronic control device can perform the shut-off function without requiring access to the internally mounted component.
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
The solution enables early detection and prevention of abnormal currents, reducing the need for fuse replacements and minimizing the size and cost of semiconductor fuses while ensuring safe operation of essential vehicle systems.
Implementation Method 1
a temperature detector that detects a temperature of the shut-off unit
Implementation Method 2
a current detector that detects a current flowing to a plurality of load devices
Implementation Method 3
The semiconductor fuse estimates the temperature of the harness from the value of the current flowing to the power supply line, and turns off the MOS transistor when there is a risk of the harness catching fire due to an abnormal current
Implementation Method 4
a fuse that shuts off a supply of power when an abnormal current flows through a power supply line for a long time
Data Source
AI summary
A vehicle control device using a semiconductor fuse, and enabling an increase in size of the semiconductor fuse to be suppressed and the occurrence of an abnormal current to be detected early to enable shut off of the abnormal current. The vehicle control device includes a shut-off unit that supplies and shuts off a supply of power to a plurality of load devices; a current detector that detects a current flowing to the plurality of load devices; and a temperature detector that detects the temperature of the shut-off unit. Furthermore, the vehicle control device includes a drive controller that, when the temperature of the shut-off unit detected by the temperature detector exceeds a predetermined value, controls and restricts operation of the load devices for which the priority is low, based on priorities set for each of the plurality of load devices.