Coaxial Resistor Shielding for HVDC Current Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-voltage direct current transmission systems face challenges in measuring high-frequency currents due to interference from strong electromagnetic fields, which existing measurement systems fail to mitigate effectively.
Innovation Solution
A coaxial resistor arrangement is placed on an electrically conductive housing with sensor lines guided through its interior, shielded from external influences, and connected to an electrical interface within the housing, which can generate and output measurement signals via optical waveguides, forming a Faraday cage for electromagnetic shielding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If sensor lines are placed in the outer region of the coaxial resistor, then the measurement system is simpler to implement, but the sensor lines are exposed to electromagnetic interference from high-voltage installations
Solution Approach 1:
The sensor lines are routed through the hollow interior of the coaxial resistor, nesting the signal-carrying conductors within the shielded structure of the resistor itself. This nested configuration allows the sensor lines to be protected from electromagnetic interference by the conductive housing and outer waveguide of the coaxial resistor, while maintaining a compact and integrated design.
2Reliability
If optical waveguides are used for output, then potential isolation between electrical interface and receiving device is achieved, but the device structure becomes more complex
Solution Approach 1:
The electrical signal transmission path is replaced with an optical transmission path using waveguides. The electrical interface converts electrical measurement signals to optical signals, which are then transmitted through dielectric waveguides to the receiving device. This substitution provides galvanic isolation and potential isolation, protecting the high-voltage measurement system from low-voltage electronics while maintaining signal integrity.
3Object-affected harmful factors
If the coaxial resistor is used for shielding, then measurement signals are protected from electromagnetic waves, but the sensor lines must be routed through the interior of the coaxial resistor
Solution Approach 1:
The sensor lines are pre-routed through the hollow interior of the coaxial resistor during the assembly process. The coaxial resistor is designed with a hollow interior specifically to accommodate the sensor lines, and the lines are inserted and connected before the final assembly is completed. This preliminary routing ensures that the sensor lines are properly positioned within the shielded structure and connected to the electrical interface without requiring complex post-assembly modifications.
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 significantly reduces interference from electromagnetic waves, allowing for accurate and interference-free measurement signals to be generated and output, enhancing the dynamic response of measurement systems in high-voltage direct current transmission.
Implementation Method 1
the sensor lines and therefore the measurement signals carried on the latter are shielded from external influences, in particular electromagnetic waves or radiation, by the coaxial resistor
Implementation Method 2
outputs them to the outside by means of one or more optical waveguides
Data Source
AI summary
An arrangement has a coaxial resistor. The coaxial resistor is to be placed on an electrically conductive housing, and sensor lines of the coaxial resistor are to be guided through an interior of the coaxial resistor into the interior of the electrically conductive housing and to be connected to an electrical interface in the electrically conductive housing.