Arc Extinguishing Unit With Magnetic Arc Path Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing arc extinguishing devices for air circuit breakers are limited in effectively extinguishing arcs without damaging magnets and require excessive design changes, and they do not provide a stable path for arc discharge, especially when using air as the extinguishing medium.
Innovation Solution
An arc extinguishing unit with a magnetic field formed by an extinguishing magnet positioned between support plates and grids, which directs the arc path externally and prevents magnet damage, using a grid cover with a mesh part and blocking plate to secure the arc path and maintain magnet stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an extinguishing magnet is provided to form a magnetic field for arc movement, then arc extinguishing performance is improved, but the magnet may be damaged by the arc
Solution Approach 1:
A protective plate is positioned between the arc and the extinguishing magnet to serve as an intermediary barrier. The plate absorbs or deflects the arc's harmful effects while allowing the magnetic field to pass through and guide the arc, thus protecting the magnet from direct arc contact while maintaining arc extinguishing functionality
Solution Approach 2:
The extinguishing magnet is nested within a protective structure (cover or housing) that shields it from direct arc exposure. This nested arrangement allows the magnet to generate its magnetic field for arc control while being physically protected from arc damage by the surrounding protective structure
2Speed
If the magnet is exposed to form a magnetic field for arc path formation, then arc movement is improved, but the magnet position becomes unstable
Solution Approach 1:
The extinguishing magnet is nested within a dedicated accommodating space or housing that provides mechanical support and positional stability. This nested structure allows the magnet to remain fixed in position while still generating an effective magnetic field for rapid arc movement
Solution Approach 2:
The magnet is pre-positioned and secured in its accommodating space before arc generation occurs. This preliminary positioning ensures the magnet maintains stable position during operation, providing consistent magnetic field generation for controlled arc movement without requiring active stabilization during arc extinction
3Reliability
If a grid structure is used to induce arc toward the extinguishing device, then arc extinguishing is improved, but the arc path may not be effectively formed away from the guide plate
Solution Approach 1:
The grid structure is segmented into multiple sections or zones, with different portions serving different functions: one section induces the arc toward the extinguishing device while another section guides the arc away from the guide plate. This segmentation allows independent optimization of each zone for its specific function, simplifying the overall arc path control
Solution Approach 2:
Different regions of the grid structure have different geometric properties or orientations tailored to local requirements. The grid portion near the arc source is configured to induce arc formation, while the portion closer to the guide plate is configured to direct the arc away, creating locally optimized conditions for effective arc path formation without excessive overall complexity
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 quickly extinguishes and moves arcs externally, preventing magnet damage and allowing for easy manufacturing, while maintaining magnet stability and securing the arc path for effective discharge.
Implementation Method 1
an extinguishing magnet that forms a magnetic field in a direction from the grid cover toward the grid or a direction from the grid toward the grid cover
Data Source
AI summary
An arc extinguishing unit and an air circuit breaker comprising same are disclosed. The arc extinguishing unit according to an embodiment of the present disclosure comprises an arc extinguishing magnet located above a grid. The arc extinguishing magnet forms a magnetic field in the arc extinguishing part and in a fixed contact and a movable contact that are located adjacent to the arc extinguishing part. An arc generated as the fixed contact and the movable contact are separated from each other receives an electromagnetic force in the formed magnetic field. The electromagnetic force passes through the grid and is formed in a direction facing the exterior of the arc extinguishing part. Thus, the generated arc may be quickly extinguished and moved.