Explosive Short-Circuit Switching Device for Arc Extinguishing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing medium-voltage switchgear faces challenges in quickly and reliably extinguishing arcs during faults, leading to pressure increases and potential explosions, due to slow reaction times and complex, costly three-phase short-circuiters that reduce switching and insulating capacity over time.
Innovation Solution
A short-circuit switching device with a conical design and explosive charge for rapid contact closure and self-locking, utilizing a sensor for immediate arc detection and actuation within 10 milliseconds, ensuring the short-circuit contact remains closed without additional forces, preventing arcing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional short-circuiters are used, then arc faults can be protected against, but reaction time is too slow and the system becomes technically complicated and expensive
Solution Approach 1:
The patent replaces conventional slow mechanical three-phase short-circuiters with a single-phase vacuum-based short-circuiting element actuated by an explosive charge. This mechanical substitution achieves much faster reaction time (within 10 milliseconds) while simplifying the system structure and reducing costs.
Solution Approach 2:
The invention segments the protection function by using a single-phase short-circuiting element instead of three-phase systems. The explosive charge actuation mechanism is separated from the electrical contacts, allowing independent optimization of each component for speed and reliability.
2Volume of moving object
If cylindrical short-circuit switching elements are used, then compact design is achieved, but bearing clearances and ignition deviations cause the shot to be unaimed and contacts to touch only at the edge, resulting in considerable arcing
Solution Approach 1:
The patent employs conical surfaces instead of cylindrical ones for both the short-circuiting element and the counter-contact. The conical geometry provides self-aligning properties that compensate for bearing clearances and ignition deviations, ensuring reliable full-surface contact closure even with manufacturing tolerances and wear.
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
This solution provides a compact, cost-effective, and reliable method to quickly extinguish arcs, reducing mechanical and thermal stress, and maintaining electrical properties throughout the switchgear's service life.
Implementation Method 1
a short-circuit switching device (9) with a short-circuit switching element (5) and a contact structure (8) having conical structuring, which is actuated by means of an explosive charge (1) within a time T≦10 milliseconds
Implementation Method 2
the short-circuit switching element (5) is provided with an outer cone and the contact structure electrically connected to the three-phase conductor is provided with a correspondingly complementary cone opening
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a method for extinguishing an interference arc in a mid- and high-tension switchgear assembly, with which, according to the preamble of patent claims 1 and 3, at least one short circuit element is connected between the phases of a three-phase alternating current distributor. In order to extinguish the interference arc more reliably, the invention proposes that the interference is detected by sensors and that the short circuit switching element is fired by means of an explosive charge that impacts directly on the short circuit switching element on a conical contact structure complementary to the short circuit element connected to the three-phase power lines in such a way that, with the help of the complementary contours of the short circuit switching element and the three-phase power lines, self-locking persistence is achieved in the short circuit condition without having to apply a retaining force.