Backup Power Circuit Fuse Layout for Ground Fault Protection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing power supply systems with voltage conversion units require complex configurations and increased costs due to the need for switches and control circuits to protect against ground fault currents.

Innovation Solution

Incorporating first and second cutoff units, specifically fuses, at the output and input units of the voltage conversion unit to prevent ground fault currents, eliminating the need for additional switches and control circuits.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a switch and control circuit are provided to protect the voltage conversion unit from ground fault current, then the voltage conversion unit is protected from damage, but the device complexity and cost increase

Engineering Contradiction:

Improveprotection from ground fault currentVSAvoidcircuit configuration

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces expensive, complex switches and control circuits with inexpensive fuses that are designed to be replaced rather than repaired. The fuses provide ground fault protection through a simple, disposable mechanism that eliminates the need for complex control systems while maintaining reliability.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent extracts the protection function from the complex switch-and-control-circuit system and implements it separately through dedicated fuse elements. This separation allows the protection mechanism to be simplified while maintaining its effectiveness in preventing ground fault damage.

Inventive Principle:

Principle #2Taking out (Extraction)

2Reliability

If a switch and control circuit are provided to protect the voltage conversion unit from ground fault current, then the voltage conversion unit is protected from damage, but the manufacturing cost increases

Engineering Contradiction:

Improveprotection from ground fault currentVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Device complexity

If fuses are used instead of switches and control circuits, then the device complexity and cost are reduced, but the protection mechanism becomes less controllable

Engineering Contradiction:

Improvecircuit configurationVSAvoidcontrol capability

Core Design Contradiction:

Device complexityVSEase of operation

Solution Approach 1:

The fuses provide automatic protection without requiring external control. When a ground fault occurs, the fuse automatically blows to interrupt the fault current, eliminating the need for control circuits or manual intervention. This self-service mechanism simplifies the system while maintaining effective protection.

Inventive Principle:

Principle #25Self-service

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 system effectively protects the voltage conversion unit from ground fault currents with a simpler and less expensive configuration, preventing damage and reducing the risk of smoke or ignition.

Implementation Method 1

a first cutoff unit that is provided at an output unit of the voltage conversion unit and that cut off a current when a ground fault current flows in; and a second cutoff unit that is provided at an input unit of the voltage conversion unit and that cut off a current when a ground fault current flows in. The first cutoff unit is a first fuse that cuts off a current by being blown when a ground fault current flows thereinto.

Methodology Applied

Scientific EffectFusing:

Data Source

PatentUS20250392141A1Power supply system

Publication Date: 2025.12.25 YAZAKI CORP

AI summary

A power supply system includes a power supply supplying power to a load via a first wiring, a storage battery storing power supplied from the power supply via a second wiring connected to the first wiring and supplying power to the load when the power supply fails to supply power to the load, a first switch provided on the first wiring between a connection portion with the second wiring and the power supply, a voltage conversion unit connecting the second wiring and the storage battery and stepping up and down a voltage of power supplied from the power supply, a second switch connected in parallel with the second wiring and the voltage conversion unit, a first fuse provided at an output unit of the voltage conversion unit and cutting off a current by being blown when a ground fault current flows thereinto.