Segmented Coated Electrode Bushing for Low-Capacitance Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing bushings for medium-voltage switchgear face challenges in direct measurement of physical quantities due to increased capacitance with longer coated electrodes, which exceeds maximum permissible limits, making it impossible to use them for measurement beyond a certain length.
Innovation Solution
The bushing features a coated electrode with axial interruptions, forming electrically insulated segments with terminals, reducing capacitance and allowing for the connection of measurement devices for voltage, temperature, or partial discharge measurements, while maintaining field control at lower manufacturing costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the coated electrode is made longer to enable measurement of physical quantities, then the measurement capability is improved, but the capacitance increases beyond maximum permissible limits
Solution Approach 1:
The coated electrode is divided into multiple electrically insulated segments by introducing axial interruptions. This segmentation reduces the capacitance of each individual segment while maintaining the overall length and measurement capability of the electrode. The interruptions create electrically isolated sections that can be independently connected to measurement devices, thereby resolving the contradiction between needing long electrode length for measurement and limiting capacitance to permissible values.
2Ease of manufacture
If the coated electrode is used for direct measurement without interruptions, then the manufacturing cost is reduced, but the capacitance exceeds maximum permissible limits preventing measurement usage
Solution Approach 1:
The electrode is segmented into multiple insulated sections through axial interruptions, which reduces capacitance to permissible levels while maintaining manufacturing simplicity. This segmentation allows the electrode to be used for direct measurements without requiring complex external measurement systems.
Solution Approach 2:
The electrical parameters of the electrode are modified by introducing interruptions that change the capacitance from excessive levels to permissible levels. This parameter change enables the electrode to meet measurement requirements while maintaining cost-effectiveness.
3Device complexity
If the coated electrode is made longer to reduce the number of components, then the device complexity is reduced, but the capacitance increases making measurement impossible
Solution Approach 1:
The electrode is divided into multiple segments with axial interruptions, reducing capacitance to permissible levels while maintaining the long length needed to avoid additional components. The segmented design allows direct measurement capability without requiring external measurement devices or additional components.
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 design enables direct measurement of physical quantities with reduced capacitance, allowing for various connections of measurement devices, reducing costs and increasing versatility in bushing manufacturing and usage.
Implementation Method 1
an insulating material coating the conductor
Implementation Method 2
the capacitance of the two segments of the coated electrode is reduced in accordance with the number of segments
Data Source
AI summary
A bushing for gas-insulated switchgear has an electrical conductor, which has a longitudinal axis and which is embedded in an insulating material, and a coated electrode that is arranged coaxially spaced apart from the conductor and that is formed from a plurality of segments.