DC Load Zone Fault Localization Using Fuse Voltage Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In DC networks, identifying a faulty electrical device during a short circuit is challenging when the fuse does not trip quickly enough, making it difficult to determine which device is faulty, especially when the electronic switch disconnects the load zone from the power source before the fuse can trip.
Innovation Solution
The method involves using voltage sensors to measure the voltage across fuses in the load zone, determining the polarity and amplitude of the voltage to identify the faulty device, and optionally using a peak rectifier to store peak voltage values for post-fault analysis, eliminating the need for current transformers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If voltage sensors are used to measure voltage across fuses for fault localization, then fault detection precision is improved, but device complexity increases due to additional sensors and evaluation requirements
Solution Approach 1:
The patent uses the fuse itself as an intermediary element for fault detection. By measuring the voltage across the fuse, the system indirectly detects fault conditions without requiring direct current measurement. This approach leverages the existing fuse component to provide fault information, reducing the need for additional complex sensing infrastructure while maintaining measurement precision.
Solution Approach 2:
The patent replaces traditional current-based fault detection methods with voltage-based detection. Instead of measuring current directly (which would require current transformers or hall sensors), the system measures voltage across the fuse, substituting a simpler electrical measurement approach that achieves the same fault detection objective with reduced complexity.
2Reliability
If peak voltage values are stored for post-fault analysis, then fault localization capability is improved, but energy consumption increases due to continuous monitoring and data storage
Solution Approach 1:
The system performs preliminary action by storing peak voltage values during normal operation and transient states, before a fault occurs. This pre-capture of voltage data ensures that critical fault information is preserved even if the fault happens rapidly. The evaluation unit can then analyze these pre-stored values to localize faults without requiring continuous high-power processing during fault events.
Solution Approach 2:
Instead of continuously analyzing all voltage data in real-time (excessive action), the system selectively stores and processes only peak voltage values (partial action). This approach captures the essential fault information contained in voltage peaks while significantly reducing the computational and energy burden compared to continuous full-waveform analysis.
3Reliability
If the electronic switch disconnects the load zone quickly from the power source, then protection reliability is improved, but fault identification becomes more difficult due to reduced current flow
Solution Approach 1:
The patent converts the harmful effect of rapid disconnection (which reduces current flow and makes fault detection harder) into a beneficial measurement opportunity. By measuring the voltage across the fuse immediately upon disconnection, the system captures fault information that would otherwise be lost. The rapid disconnection that protects the system also creates a distinct voltage signature across the fuse that clearly indicates fault conditions, turning a protective action into a diagnostic opportunity.
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 allows for reliable fault localization without current transformers, reducing costs and losses, and enables efficient identification of faulty devices even after the electronic switch has disconnected the load zone, using stored peak voltage values as criteria.
Implementation Method 1
The voltage sensor (7) measures a voltage (uSx) across the fuse (5)
Implementation Method 2
optionally using a peak rectifier to store peak voltage values for post-fault analysis
Data Source
Figure 1
Figure 2~5
AI summary
The invention relates to a load zone (1) comprising an electronic switch (2), a DC bus (3), a connection (30) for supplying the load zone (1) with electrical energy, and at least two electrical devices (4), the electronic switch (2) being arranged between the connection (30) and the DC bus (3), the electrical devices (4) each being electrically connected in parallel with the DC bus (3). To improve fault detection and fault localization in the load zone (1), a fuse (5) is arranged between the DC bus (3) and the particular electrical device (4), a voltage sensor (7) being arranged so as to detect a voltage (uSx) across the fuse (5). Furthermore, the invention relates to a DC system (10) having such a load zone (1) and at least one energy source (6), the energy source (6) being connected to the connection (30) of the load zone (1). The invention further relates to a method for operating such a load zone (1) or such a DC system (10), wherein a defective device of the electrical devices (4) is identified on the basis of the voltage (uSx) across the fuse (5) in that the voltage (uSx) across the fuse (5) exceeds a specifiable limit value.