Low-Voltage Circuit Breaker Functional Check Before Reclosing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing protective switching devices for low-voltage circuits, particularly those with electronic interruption units, lack sufficient safety measures to ensure reliable operation and prevent accidental activation of faulty components, leading to potential hazards.
Innovation Solution
A protective switching device with a mechanical isolating contact unit and an electronic interruption unit, utilizing semiconductor-based switching elements, includes a current sensor, control unit, and voltage sensors to monitor and control current and voltage levels, ensuring safe operation by preventing activation of faulty components through fault detection and enabling mechanisms.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an electronic interruption unit with semiconductor-based switching elements is used, then the circuit breaker can provide advanced protection functions and precise control, but the risk of accidental activation of faulty components increases
Solution Approach 1:
The patent implements a preliminary functional test of the electronic interruption unit before the circuit breaker is activated. The control unit commands the electronic interruption unit to perform test operations in advance, verifying proper functionality before allowing normal operation. This preliminary action prevents faulty components from being activated, resolving the contradiction between advanced protection functions and accidental activation risks.
Solution Approach 2:
The patent establishes a feedback mechanism where the control unit continuously monitors the operational status of the electronic interruption unit. Based on feedback from functional tests and operational parameters, the control unit determines whether to permit or prevent circuit breaker activation. This feedback loop ensures that faulty components are identified and isolated, maintaining reliability while preventing accidental activation.
2Reliability
If functional tests are performed on the electronic interruption unit before activation, then safety is improved, but the device complexity increases
Solution Approach 1:
The patent merges the functional test capabilities with the existing control unit of the circuit breaker. The control unit integrates both the testing functions and the normal operational control functions, eliminating the need for separate testing equipment or additional complex control systems. This merging approach improves safety through functional testing while minimizing the increase in device 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
Enhances operational reliability and safety by preventing accidental activation of faulty components, ensuring only functional devices are switched on, thereby increasing safety in low-voltage electrical circuits.
Implementation Method 1
the electronic interruption unit can be switched by semiconductor-based switching elements into a high-resistance state of the switching elements to prevent a current flow or a low-resistance state of the switching elements to allow current flow
Implementation Method 2
a current sensor unit for determining the level of the current in the low-voltage circuit
Implementation Method 3
the voltage sensor unit determines a voltage level across the electronic interruption unit
Implementation Method 4
a bimetallic protective element or bimetallic element is used to trip (interrupt) the circuit in the event of a prolonged overcurrent (overcurrent protection) or thermal overload (overload protection)
Implementation Method 5
An electromagnetic release with a coil is used for brief tripping when an overcurrent limit is exceeded or in the event of a short circuit (short-circuit protection)
Implementation Method 6
One or more arc-quenching chambers or arc-quenching devices are provided
Data Source
Figure 1
Figure 2
Figure 3~3A
AI summary
The invention relates to a circuit breaker for protecting an electric low-voltage circuit, comprising: - a housing with at least one grid-side connection and a load-side connection, and - a mechanical separating contact unit which is connected to an electronic interruption unit in series, wherein - the mechanical separating contact unit is paired with the load-side connection, and the electronic interruption unit is paired with the grid-side connection, - the level of the current in the low-voltage circuit, in particular between the grid-side phase conductor connection and the load-side phase conductor connection, is ascertained, - a process for preventing a current flow in the low-voltage circuit is initiated if current thresholds and/or current/time thresholds are exceeded, - a measurement impedance is provided between two conductors of the low-voltage circuit, said measurement impedance being connected to the connection between the mechanical separating contact unit and the electronic interruption unit (EU), and - while the contacts of the mechanical separating contact unit are open and the electronic interruption unit is switched to a high-ohmic state, the electronic interruption unit is switched to a low-ohmic state for a first duration in order to check the functionality of the circuit breaker.