Synchronous Rectifier Fault Clearing via Segmented Fuses
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Voltage regulation systems in closed electrical systems, such as spacecraft, often fail in shorted modes due to inadequate control of current diversion, leading to inefficiencies and weight penalties from high power dissipation.
Innovation Solution
A fault-tolerant synchronous rectifier regulator system utilizing a high side switch, low side switch, and a combination of fuses to automatically clear faults, reducing power dissipation and weight by maintaining current flow through the electrical bus even when components short or fail.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If voltage regulation systems use conventional control circuits to divert current away from power sources, then voltage regulation of the electrical bus is maintained, but the system is prone to shorted mode failures and high power dissipation
Solution Approach 1:
The patent divides the fault protection function into multiple independent fuse elements (first fuse in series with the load, second fuse in series with the power source) rather than using a single complex control circuit. This segmentation allows individual fuse elements to handle specific fault conditions independently, improving reliability while minimizing energy loss through simple thermal-magnetic operation.
Solution Approach 2:
The patent employs fuse elements as disposable protective components that automatically open on fault occurrence. These fuses are designed to be replaced rather than repaired, providing reliable fault clearance at low cost and minimal energy expenditure compared to complex active protection circuits.
2Reliability
If fault protection circuits are added to prevent shorted mode failures, then system reliability improves, but device complexity and weight increase
Solution Approach 1:
The protection function is segmented into simple fuse elements distributed at different locations in the circuit (series with load, series with power source) rather than centralized complex control logic. Each fuse handles specific fault scenarios independently, reducing overall system complexity.
Solution Approach 2:
The fuse elements provide automatic fault clearance without requiring external control circuits or active management. The fuses self-actuate based on fault conditions (overcurrent, short circuits) through their inherent thermal-magnetic characteristics, eliminating the need for complex control electronics.
3Reliability
If automatic fault clearing is implemented using traditional methods, then faults are cleared quickly, but power dissipation and system weight increase
Solution Approach 1:
The patent uses lightweight fuse elements as the primary automatic fault clearing mechanism. These disposable fuses provide rapid fault clearance without requiring heavy-duty active protection devices, control electronics, or large thermal management systems, thereby minimizing weight while maintaining automatic protection functionality.
Solution Approach 2:
The patent extracts the fault protection function from complex active control systems and implements it through passive fuse elements. This extraction eliminates the need for heavy control circuits, sensors, and power management electronics, significantly reducing system weight while preserving automatic fault clearing capability.
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
A fault tolerant synchronous rectifier regulator system and method are disclosed. In the system and method, a high side switch is operable to be coupled to an electrical bus, and a low side switch is coupled to a common ground. In addition, a first fuse is coupled to the high side switch and the low side switch, and operable to open in response to a first fault. Furthermore, a second fuse is coupled to the high side switch and the first fuse, and operable to be coupled to a current source and to open in response to a second fault.