Arc-Driven Switchgear for Reliable High-Speed Contact Actuation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional switchgear for modular multilevel converters requires periodic replacement of drive units, leading to increased costs and potential reliability issues due to the use of blasting techniques involving gunpowder.

Innovation Solution

A switchgear design incorporating a fixed and movable electrode with a piston-driven arc generation mechanism, utilizing a fuse or switch to generate an arc and drive the movable electrode for high-speed operation without the need for periodic replacement, leveraging a vacuum container and arc generation mechanism to bridge a terminal unit and open a circuit, thus eliminating the need for explosive materials.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If a blasting technique using gunpowder is used to drive the movable electrode, then the switchgear can operate at high speed, but the drive unit requires periodic replacement and generates replacement costs

Engineering Contradiction:
Improveoperating speed of switchgearVSAvoidreliability of drive unit
Core Design Contradiction:
SpeedVSReliability

Solution Approach 1:

The patent replaces the mechanical blasting system (gunpowder-based drive unit) with an electromagnetic arc generation mechanism. The arc generates thermal energy that expands gas to drive the piston, eliminating the need for periodic replacement of explosive materials while maintaining high-speed operation capability.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the energy conversion parameters from chemical energy (gunpowder) to electrical energy (arc discharge). By controlling the electrical parameters of the arc generation mechanism, the system achieves reliable, repeatable high-speed actuation without the degradation issues inherent in consumable blasting materials.

Inventive Principle:
Principle #35Parameter changes

2Speed

If a blasting technique using gunpowder is used to drive the movable electrode, then the switchgear can operate at high speed, but replacement costs are generated

Engineering Contradiction:
Improveoperating speed of switchgearVSAvoidmanufacturing cost
Core Design Contradiction:
SpeedVSEase of manufacture

Solution Approach 1:

The patent replaces the mechanical blasting system (gunpowder-based drive unit) with an electromagnetic arc generation mechanism. The arc generates thermal energy that expands gas to drive the piston, eliminating the need for periodic replacement of explosive materials while maintaining high-speed operation capability.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The arc generation mechanism uses the existing electrical circuit to power itself - the same circuit that needs to be opened or closed operates the drive mechanism. This eliminates the need for separate power sources or replacement of consumable materials, reducing long-term operational costs.

Inventive Principle:
Principle #25Self-service

3Reliability

If an arc generation mechanism is used to replace the blasting technique, then periodic replacement of drive unit is eliminated, but the device complexity increases

Engineering Contradiction:
Improvereliability of drive unitVSAvoidcomplexity of switchgear
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The arc generation mechanism serves multiple functions: it acts as both the drive unit for the piston and the switching element for the circuit. This multi-functionality reduces overall device complexity despite the advanced mechanism, as one component replaces what would traditionally require separate drive and switching systems.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges the drive mechanism and the circuit interruption function into a single integrated system. The arc generation mechanism both drives the piston to open/close contacts and simultaneously creates the arc to interrupt the circuit, eliminating the need for separate components.

Inventive Principle:
Principle #5Merging (Combining)

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 eliminates the need for periodic replacement of drive units, ensuring long-term reliability and high-speed operation while simplifying assembly and reducing costs by avoiding explosive technologies.

Implementation Method 1

an arc generation mechanism including metal and provided in the container at a position opposite to the fixed electrode, the arc generation mechanism bridging a terminal unit connected to an external circuit, the arc generation mechanism opening a circuit with the terminal unit when energized to generate an arc at the opened portion

Methodology Applied
Scientific EffectArc generation: Electric Arc

Implementation Method 2

the arc generation mechanism opening a circuit with the terminal unit when energized to generate an arc at the opened portion

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentEP4138106B1Switchgear and power converter
Publication Date: 2024.11.13 MITSUBISHI ELECTRIC CORP
  • EP4138106B1 patent drawingFigure 1
  • EP4138106B1 patent drawingFigure 2~2(3)
  • EP4138106B1 patent drawingFigure 3

AI summary

An object of the present invention is to provide a switchgear that reduces a cost of periodic replacement of a drive unit and ensures reliability. A switchgear of the present invention includes a fixed electrode (2), a movable electrode (3) provided to face the fixed electrode (2), the movable electrode (3) being contactable with and separable from the fixed electrode (2), a piston (11) provided opposite to the fixed electrode (2) to drive the movable electrode (3) via a movable shaft (4) connected to the movable electrode (3), a container (12) to accommodate the piston (11), and an arc generation mechanism (20A) bridging including metal and provided in the container (12) at a position opposite to the fixed electrode (2), the arc generation mechanism (20A) bridging a terminal unit (22) connected to an external circuit, the arc generation mechanism (20A) bridging opening a circuit with the terminal unit (22) when energized to generate an arc (23) at an opened portion.