High Voltage Resistor Shielding for Phasing Meter Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High voltage phasing meters suffer from measurement errors and uneven electrical stress due to non-uniform voltage distribution caused by stray capacitance across high voltage resistors, leading to resistor degradation and inaccurate current flow.
Innovation Solution
The implementation of metallic collars at opposite ends of the high voltage resistors to form compensative capacitance, providing uniform current distribution and reducing stray capacitance effects, thus stabilizing the electrical stress and improving measurement accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If high voltage resistors are used in phasing meters, then voltage measurement capability is achieved, but non-uniform voltage distribution due to stray capacitance causes measurement errors and electrical stress concentration
Solution Approach 1:
A shielding structure is introduced as an intermediary element between the high voltage resistor and the surrounding environment. The shield, positioned around the resistor, intercepts stray capacitive fields and redirects them, preventing unwanted capacitance from forming between the resistor and ground. This mediator structure eliminates the root cause of non-uniform voltage distribution while maintaining the resistor's measurement function.
Solution Approach 2:
The invention converts the harmful effect of stray capacitance into a beneficial controlled capacitance. By introducing the shielding structure, the unpredictable stray capacitance is replaced with a known, controlled capacitive effect that can be accounted for in the measurement circuit. The shield creates a defined electric field geometry that transforms the problematic distributed capacitance into a manageable parameter.
2Device complexity
If high voltage resistors are used without shielding, then device complexity is reduced, but stray capacitance causes non-uniform voltage distribution and current measurement errors
Solution Approach 1:
The shielding structure serves as an intermediary that separates the high voltage resistor from the ground plane, preventing direct capacitive coupling. This simple additive structure introduces minimal complexity while dramatically improving measurement accuracy by eliminating the primary source of error - the stray capacitance between the resistor and ground.
3Ease of manufacture
If no electrostatic shielding is provided, then manufacturing cost and device complexity are minimized, but voltage stress concentration degrades resistor material at high voltage ends
Solution Approach 1:
The shield acts as a protective intermediary that distributes the electric field more evenly along the resistor length. By positioning conductive shielding elements around the resistor, the structure creates a more uniform electric field distribution, preventing excessive voltage stress concentration at the high voltage end and thereby protecting the resistor material from degradation.
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 solution minimizes measurement errors and ensures a more uniform voltage distribution along the resistors, enhancing the reliability and accuracy of high voltage phasing meter readings.
Implementation Method 1
A capacitance, formed by metallic collars, across the resistor compensates for stray capacitance from the resistor to ground
Implementation Method 2
A capacitance, formed by metallic collars, across the resistor compensates for stray capacitance from the resistor to ground
Data Source
AI summary
A phasing voltage meter comprises first and second probes. Each probe comprises an insulated shield supporting an electrode for contacting a high voltage electrical conductor. The shield houses a high voltage resistor connected in series with the electrode. A capacitance formed by a metallic collar across the resistor compensates for stray capacitance across the resistor. A meter comprises a housing enclosing electrode circuit for measuring phasing voltage. The electrical circuit measures voltage across the electrodes and provides an output representing phasing voltage.