Optical Fiber Temperature Sensing for Current Imbalance Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for detecting current imbalance in electrical energy distribution networks, such as those using current transformers, are bulky, heavy, and space-intensive, making them impractical for high-voltage and high-current applications like aircraft electrical systems, where weight and space constraints are critical.
Innovation Solution
The use of optical fibers with temperature sensing sections, such as Fiber Bragg Gratings, to detect current imbalances by measuring temperature changes along electrical energy distribution cables, allowing for compact and lightweight current imbalance detection systems.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If current transformers are used to detect current imbalance, then measurement precision is improved, but weight increases
Solution Approach 1:
The patent replaces traditional current transformers (electromagnetic/mechanical systems) with optical fibers that use thermal contact to detect current imbalance. The optical fiber system measures temperature differences between cables caused by unequal current distribution, substituting direct electrical measurement with thermal-field measurement, thereby eliminating the weight of heavy current transformers while maintaining detection capability
Solution Approach 2:
The patent introduces temperature as an intermediary parameter to detect current imbalance. Instead of directly measuring current distribution, the system uses temperature sensors (optical fibers) to detect temperature differences between cables, which are caused by unequal current flow. This intermediary approach allows indirect measurement of current imbalance with lightweight equipment
2Measurement precision
If current transformers are used to detect current imbalance, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent replaces complex electromagnetic current transformers with simple optical fiber temperature sensors. The optical fiber system requires only thermal contact with the cables and optical interrogation equipment, eliminating the complex electromagnetic structures, windings, and magnetic cores of current transformers, thereby significantly reducing device complexity
Solution Approach 2:
The optical fiber temperature sensors serve multiple functions: they detect temperature for current imbalance monitoring, can provide fire detection capabilities, and are compatible with various cable types and voltage levels. This multi-functionality reduces the need for specialized equipment for different applications, simplifying the overall system
3Measurement precision
If current transformers are used to detect current imbalance, then measurement precision is improved, but volume increases
Solution Approach 1:
The patent replaces bulky current transformers with thin optical fibers that can be easily attached to or embedded in cables. The optical fiber sensors have minimal volume compared to current transformers, allowing installation in confined spaces without interfering with cable bundling or requiring additional mounting space
Solution Approach 2:
The optical fiber temperature sensors can be embedded within or attached to the cable structure itself, integrating the detection system with the existing cable infrastructure. This nesting approach eliminates the need for separate external mounting space, allowing the detection system to occupy minimal additional volume
4Volume of moving object
If cables are bundled to save space, then volume is reduced, but current imbalance detection becomes more difficult
Solution Approach 1:
The patent replaces direct electrical measurement methods (current transformers requiring cable separation) with thermal field measurement using optical fibers. Since thermal conduction occurs through direct contact and proximity, the optical fiber sensors can accurately detect temperature differences between bundled cables without requiring the cables to be separated, thereby maintaining detection capability while preserving cable bundling benefits
Solution Approach 2:
The patent uses temperature as an intermediary that can be measured through thermal contact or proximity, allowing detection of current imbalance in bundled cables. The thermal field penetrates and equilibrates across the cable bundle, enabling the optical fiber sensors to detect temperature differences between individual cables within the bundle without physical separation
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 approach reduces the weight and space requirements for current imbalance detection, enhances resistance to electromagnetic interference, and enables practical implementation in space-constrained environments like aircraft, while effectively identifying current imbalances and triggering mitigation actions.
Implementation Method 1
one or more first temperature sensors of the plurality of temperature sensors are configured for thermal contact with a first electrical energy distribution element of the electrical energy distribution network; and one or more second temperature sensors of the plurality of temperature sensors are configured for thermal contact with a second, different, electrical energy distribution element of the electrical energy distribution network
Implementation Method 2
each temperature sensor being implemented by a temperature sensing section of an optical fiber, each temperature sensing section being arranged to produce, in response to an optical input signal, an optical output signal indicative of the temperature of the temperature sensing section
Data Source
AI summary
An apparatus and method for detecting current imbalance between two or more electrical energy distribution elements of an electrical energy distribution network are disclosed. Each of a plurality of temperature sensors are implemented by a temperature sensing section of an optical fiber arranged to produce, in response to an optical input signal, an optical output signal indicative of the temperature of the temperature sensing section. First and second temperature sensors of the plurality are in thermal contact with first and second electrical energy distribution elements, respectively, to determine first and second temperature characteristics thereof based on the respective output signals. A current imbalance between the first and second elements is detected based on a comparison of the first temperature characteristic with the second temperature characteristic.