DC Load Switch Contact Motion for Fast Arc Extinction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing switching devices face challenges in safely switching off high DC currents, particularly above 100 A, and short-circuit currents, due to the risk of contact welding and arc re-ignition, requiring efficient arc extinguishing and a strong dynamic magnetic blow field to prevent damage and ensure galvanic isolation.
Innovation Solution
A compact, remote-controlled switching device with a movable switching component that performs a combination of rotational and translational movement, utilizing an E-shaped component and magnetic actuator to create a dynamic magnetic blow field, along with arc guiding rails and deionization-extinguishing chambers to quickly extinguish arcs and prevent welding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If a compact switching device is used for high DC currents, then the device size is reduced, but the ability to safely switch off short-circuit currents deteriorates due to insufficient arc extinction capability
Solution Approach 1:
The switching device is segmented into distinct functional zones: a first switching zone with a first arc extinguishing chamber for normal switching operations, and a second switching zone with a second arc extinguishing chamber for short-circuit current interruption. This segmentation allows each zone to be optimized for its specific function while maintaining a compact overall device structure.
Solution Approach 2:
The patent introduces a vertical dimension by stacking arc extinguishing chambers above each other in the switching device. The first arc extinguishing chamber is arranged horizontally, while the second arc extinguishing chamber is arranged vertically above it, utilizing three-dimensional space to accommodate multiple arc extinction functions within a compact footprint.
2Loss of time
If the switching contacts are opened quickly to extinguish arcs, then the arc extinction time is reduced, but contact welding increases due to high current forces
Solution Approach 1:
Arc extinguishing chambers with arc splitter plates are introduced as intermediary structures between the switching contacts and the external environment. These chambers capture and extinguish arcs generated during contact opening, preventing direct arc exposure to the contacts while enabling rapid extinction. The arc splitter plates divide the arc into multiple smaller arcs that are easier to extinguish.
Solution Approach 2:
The switching device applies a preliminary magnetic blow field before the arc fully develops during contact opening. This magnetic field, generated by the magnetic actuator, acts in advance to drive the arc away from the contacts and into the arc extinguishing chamber, preventing contact welding before it can occur.
3Speed
If a magnetic actuator is used to drive the switching component, then the switching speed is improved, but the device complexity increases
Solution Approach 1:
The magnetic actuator serves multiple functions simultaneously: it generates the magnetic blow field for arc extinction, provides the driving force for switching component movement, and creates the magnetic field necessary for current commutation. This multi-functionality reduces the need for separate components and simplifies the overall device structure despite the high switching speed requirement.
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 reliable switching of high currents and short-circuit currents with a high number of operations, achieving fast arc extinction and reduced welding tendency, ensuring safe operation and extended device lifespan by minimizing arc re-ignition and contact damage.
Implementation Method 1
a magnetic actuator, wherein the first movable contact is in contact with the first fixed contact and the second movable contact is in contact with the second fixed contact in a switched-on state of the switching component
Implementation Method 2
the switching component is configured to move between the switched-on state and the switched-off state by at least a rotational movement of the switching component and a translational movement of the supporting device
Implementation Method 3
an arc guiding assembly being provided for guiding an arc arising between a first and second contact toward an extinguishing device
Data Source
AI summary
A switching device for guiding and switching of load currents includes: a movable switching component having a first movable contact and a second movable contact; a first fixed contact and a second fixed contact; a supporting device for supporting the switching component; and a magnetic actuator. The first movable contact is in contact with the first fixed contact and the second movable contact is in contact with the second fixed contact in a switched-on state of the switching component. The first movable contact is electrically separated from the first fixed contact and the second movable contact is electrically separated from the second fixed contact in a switched-off state of the switching component. The switching component is arranged such that the switching component moves between the switched-on state and the switched-off state by at least a rotational movement of the switching component and a translational movement of the supporting device.