Segmented Superconducting Current Limiter with Passive Elements
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current limiting devices, particularly superconducting ones, risk damage from fault currents, and existing methods for controlling fault currents are inadequate in protecting both the device and the components within the electrical power system.
Innovation Solution
A current limiting device comprising a first and second current limiting unit, each configured to handle currents above specific threshold values, and a passive element unit connected in series, allowing the current path to change based on the applied current magnitude, ensuring that fault currents are diverted through alternative paths to prevent damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a fault current over a certain level is applied to the superconducting current limiting device, then the electrical resistance of the superconducting element increases rapidly, but the superconducting element may be damaged and has adverse influence on devices requiring continuous current
Solution Approach 1:
The current limiting device is divided into multiple current limiting units with different threshold values. Each unit handles a specific range of fault currents, allowing the system to protect components effectively while preventing damage to the superconducting elements by distributing the fault current management across segmented units.
Solution Approach 2:
The impedance values of the current limiting units are dynamically changed by the applied electric current. As the current increases, the impedance changes to redirect the current flow through appropriate paths, ensuring continuous protection without damaging the superconducting elements.
2Reliability
If the electrical resistance of the superconducting element becomes close to infinity to limit fault current, then fault current is limited, but it has adverse influence on devices that need continuous electric current for normal operations
Solution Approach 1:
Multiple current limiting units with different threshold values are used to segment the fault current limitation process. This allows the system to limit fault currents effectively while maintaining continuous current supply to protected devices by only activating limitation when necessary.
Solution Approach 2:
The impedance values of the current limiting units are changed based on the magnitude of the applied electric current. This dynamic parameter change allows the device to maintain low impedance for normal continuous operations and high impedance only when fault currents are detected, resolving the contradiction between fault limitation and continuous current supply.
3Reliability
If multiple current limiting units with different threshold values are used to protect components, then protection effectiveness is improved, but the device complexity increases
Solution Approach 1:
Each current limiting unit is designed to perform multiple functions: normal current conduction, fault current limitation, and automatic recovery. This multi-functionality reduces the need for additional protective components, thereby limiting device complexity while maintaining effective protection through multiple threshold levels.
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 configuration effectively protects both the current limiting device and the external device from fault currents by varying the current path, preventing damage and ensuring continuous normal operation.
Implementation Method 1
The super conductor has an electrical resistance substantially close to zero (0) at a very low temperature, and the electrical resistance thereof increases rapidly with a rise of the temperature.
Data Source
AI summary
A current limiting device is provided. To elaborate, the device may include: a first current limiting unit configured to limit an electric current equal to or higher than a first threshold value applied thereto; a second current limiting unit configured to limit an electric current equal to or higher than a second threshold value applied thereto; and a passive element unit connected to both ends of the first current limiting unit, and including a first passive element and a second passive element connected in series.