Fail Operational Power Management with Blocking Elements
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Automated vehicle power systems face challenges in fail-safe operation due to potential damage from direct connection between primary and backup power sources during switchover, excessive voltage dips, and power drainage during standby mode, leading to system instability and reduced lifespan of power sources.
Innovation Solution
Implementing a fail operational power management system with independent dual power sources, using blocking elements like back-to-back MOSFETs controlled by an ECU to prevent direct connection, and a voltage sensor for fast switchover, along with a dedicated low current path for standby mode to extend battery life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If direct connection between primary and backup power sources is made during switchover, then power transfer is simplified, but damage to power sources occurs
Solution Approach 1:
The patent introduces blocking elements (MOSFETs or diodes) as intermediary components between the primary and backup power sources. These blocking elements prevent direct connection during switchover, eliminating the harmful effect of damage while maintaining a relatively simple power transfer mechanism. The blocking elements act as mediators that control the flow of power and protect the sources from direct confrontation.
Solution Approach 2:
The power transfer path is segmented into separate controlled paths using blocking elements. Instead of a single direct connection, the system divides the power flow into distinct segments that can be independently controlled and protected. This segmentation allows the system to prevent damage while maintaining operational simplicity.
2Speed
If switchover speed is increased, then voltage dips are reduced, but system stability may be compromised
Solution Approach 1:
The system performs preliminary monitoring of power source status and prepositions the blocking elements for rapid action. By continuously monitoring the primary power source and having the blocking elements ready to activate, the system can execute switchover quickly when needed while maintaining stability through controlled activation sequences.
Solution Approach 2:
The patent incorporates monitoring circuits that provide feedback on power source status and voltage levels. This feedback mechanism allows the system to detect when switchover is needed and control the blocking elements accordingly, achieving fast response while maintaining system stability through closed-loop control.
3Object-affected harmful factors
If blocking elements are used to prevent direct connection, then power source protection is improved, but device complexity increases
Solution Approach 1:
The blocking elements serve as simple intermediary components that provide protection without adding significant complexity. By using standard semiconductor devices (MOSFETs or diodes) as blocking elements, the system achieves power source protection while maintaining relatively simple circuit architecture.
Solution Approach 2:
The blocking elements automatically perform their protective function based on their inherent electrical characteristics without requiring complex control logic. The blocking elements self-regulate the power flow based on voltage and current conditions, reducing the need for additional control complexity.
4Duration of action of moving object
If standby current is reduced to extend battery life, then power consumption is minimized, but system responsiveness may be affected
Solution Approach 1:
The system uses periodic or event-driven monitoring of power source status rather than continuous high-power operation. The blocking elements and monitoring circuits remain in low-power standby mode and only become fully active when a switchover event is detected, thus extending battery life while maintaining system responsiveness through event-triggered activation.
Data Source
AI summary
A power supply device for a vehicle that includes two or more independent power sources, a simple low-power voltage monitor connected to a fast switch device, an electronic control unit (ECU), and a dedicated standby monitor element. Each power source has a separate path to connect to the load(s). That is to say, a primary path connects the primary power source to the one or more loads, and a backup path connects the backup power source to the one or more loads. Furthermore, each path includes a back-to-back blocking element, which prevents a direct connection between the primary power source and the backup power source. At standby, both or all paths are blocked except the standby monitor, ensuring extremely low quiescent current. When the system is ON, the voltage level of the power system is monitored; if the voltage level drops below a threshold level, then the paths are switched.