High-Current Shunt Measurement Through Parallel Current Division
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing shunts designed for low currents dissipate excessive power when measuring high currents, leading to inefficiency and high costs in electricity meters, and increasing dimensions to reduce power dissipation result in impractical sizes and further costs.
Innovation Solution
A current measurement device comprising a first and second electrically conductive element, where the shunt has a higher impedance than the second element, splitting the main current into two branches with different impedances, and using materials like Manganin and copper alloy to minimize power dissipation and temperature drift, with temperature compensation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a shunt designed for low currents is used to measure high currents, then the measurement function is maintained, but the power dissipation becomes excessive
Solution Approach 1:
The current path is segmented into two parallel branches: one containing the shunt (first element) and the other containing the second element. This segmentation allows the high main current to be divided, with only a portion flowing through the shunt, thereby reducing power dissipation while maintaining measurement capability.
Solution Approach 2:
The second element acts as an intermediary with low impedance that provides an alternative current path. This intermediary component enables the system to handle high currents without requiring the shunt to carry the full current load, thus reducing energy loss.
2Loss of energy
If the height and thickness of the shunt are increased to reduce power dissipation, then the power dissipation decreases, but the shunt dimensions become too large for standard electricity meters
Solution Approach 1:
Instead of increasing shunt dimensions to reduce power dissipation, the current path is segmented into parallel branches. This allows the shunt to maintain its original compact dimensions while the second element carries a portion of the current, achieving reduced power dissipation without increasing volume.
Solution Approach 2:
The impedance parameters of the circuit are changed by introducing the second element with specific impedance characteristics. This parameter change allows the system to achieve lower power dissipation through current division rather than through dimensional changes of the shunt.
3Loss of energy
If the length of the shunt is reduced to minimize power dissipation, then the power dissipation decreases, but the dissipated power remains too high even at minimum length
Solution Approach 1:
The current path is segmented into parallel branches, allowing the shunt length to be minimized while the second element provides an alternative current path. This segmentation enables both minimum shunt length and acceptable power dissipation levels to be achieved simultaneously.
Solution Approach 2:
The second element serves as an intermediary that compensates for the high power dissipation that would result from minimizing shunt length. By providing an alternative current path, it enables the shunt to be as short as needed while maintaining acceptable overall power dissipation.
4Ease of manufacture
If standard electricity meter design is used, then the meter structure is simple and costs are low, but the meter cannot dissipate the high powers required for high current measurements
Solution Approach 1:
The current measurement function is segmented between the shunt (for measurement) and the second element (for current carrying). This segmentation allows standard meter designs to be used without major modifications, maintaining manufacturing simplicity while the parallel structure reduces power dissipation requirements.
Solution Approach 2:
The second element serves multiple functions: it provides an alternative current path to reduce power dissipation, and it can be integrated into existing meter structures. This multi-functionality allows standard meters to handle high currents without requiring complete redesign, maintaining cost-effectiveness.
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
Enables accurate measurement of high currents with reduced power dissipation and lower costs, allowing integration into standard meters without significant modification, and compensating for temperature drift to maintain measurement precision.
Implementation Method 1
The materials used to make the first element (and thus the shunt) and the second element can be selected such that the impedance of the first element is much higher than that of the second element
Implementation Method 2
The current flowing in the shunt 1 is evaluated on the basis of these voltage measurements
Implementation Method 3
If necessary, the temperature drift differences in the materials used can be compensated for
Data Source
AI summary
A current measurement device arranged to measure a main current passing therethrough and includes a first element which is electrically conductive and which includes a shunt and a second element which is electrically conductive. Each end of the first element is fastened to a separate end of the second element by an electrically conductive connection such that the main current is split into a first current flowing in the first element and a second current flowing in the second element, the shunt thus making it possible to measure the first current, which is representative of the main current.