Capacitive Non-Contact Voltage Sensing via Reference Conductor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional methods for measuring AC voltage require direct electrical contact with the conductor and a reference potential, which can be inconvenient and disruptive, especially in situations where physical contact is not feasible or safe.
Innovation Solution
A non-contact capacitive voltage sensing system that uses a capacitive coupling between a conductive sense plate and an AC conductor to measure voltage without physical contact. This system includes waveform-sensing and capacitance-determining electronic circuitry to accurately determine the AC line voltage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If direct electrical contact is made with the conductor to measure voltage, then measurement accuracy is improved, but installation complexity and safety risks increase
Solution Approach 1:
The patent introduces a reference conductor as an intermediary element to establish a measurement path. Instead of directly contacting the target conductor with the voltmeter, the system uses a reference conductor that is capacitively coupled to both the target conductor and the voltmeter, enabling indirect measurement while maintaining accuracy
Solution Approach 2:
The patent replaces direct mechanical/electrical contact with capacitive coupling. The measurement system uses electric field coupling through capacitance between conductors rather than physical contact, eliminating the need for direct electrical connection while preserving measurement capability
2Measurement precision
If direct electrical contact is made with the conductor, then voltage measurement is achieved, but interruption of power flow occurs
Solution Approach 1:
The reference conductor acts as a mediator that allows voltage measurement without creating a direct measurement path that would interrupt power flow. The capacitive coupling through the reference conductor enables measurement while leaving the target conductor's power flow uninterrupted
Solution Approach 2:
The system substitutes direct electrical contact with capacitive coupling, which does not require breaking the circuit or creating a parallel path that would interrupt power flow. The electric field coupling allows measurement while maintaining continuous power flow in the target conductor
3Measurement precision
If physical contact is made with the conductor, then voltage measurement is possible, but safety risks increase
Solution Approach 1:
The patent replaces direct physical contact with capacitive coupling, which operates through electric field interaction without requiring the measurement device to physically touch the energized conductor. This substitution eliminates exposure to electrical arcs, shocks, and other contact-related hazards while maintaining measurement capability
4Measurement precision
If traditional contact-based measurement is used, then voltage can be measured, but installation time increases
Solution Approach 1:
The reference conductor serves as a pre-installed intermediary that enables measurement without requiring modification of the target conductor or complex connection procedures. Once the reference conductor is in place, voltage measurements can be performed rapidly through simple capacitive coupling
Solution Approach 2:
By replacing contact-based measurement with capacitive coupling, the system eliminates the need for making and breaking electrical connections, tightening terminals, or configuring complex measurement paths. The measurement device can be quickly positioned near the conductor to establish capacitive coupling and begin measurements
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
The system allows for accurate measurement of AC line voltage without interrupting the conductor, reduces installation time, and can detect harmonics in conductor voltages, enabling early detection of equipment failures or performance issues.
Implementation Method 1
The electrode or conductive sense plate is configured to form a capacitive coupling with a conductor
Data Source
AI summary
A non-contact electric potential meter system to determine voltage between an AC conductor and a reference potential without direct electrical contact to the conductor. A housing provides a shielded measurement region that excludes other conductors and holds power supply means; an AC voltage sensing mechanism includes a conductive sense plate and an electrical connection to the reference potential. Waveform-sensing electronic circuitry obtains an AC voltage waveform induced by capacitive coupling between the conductor and the conductive sense plate. Capacitance-determining electronic circuitry obtains a scaling factor based on the coupling capacitance formed between the conductor and the conductive sense plate. Signal processing electronic circuitry uses the AC voltage waveform and the coupling capacitance-based scaling factor to obtain the voltage between the conductor and the reference potential.