Resonant Coupling Circuit for Selective Subsystem Disconnection

The patent applies electrical resonance (analogous to mechanical vibration) by injecting a measuring signal at a specific resonant frequency through the resonant coupling circuit. This resonance amplifies the fault current signal from high-resistance faults, enabling reliable detection without complex directional monitoring devices. The resonant frequency is chosen to match the natural frequency of the fault path, creating a strong signal that can be detected by simple current measuring devices.

The patent changes the frequency parameter of the measuring signal to match the resonant frequency of the fault path. By tuning the measuring signal frequency to resonate with the fault impedance, the fault current is significantly amplified. This parameter change transforms an undetectable high-resistance fault into a detectable signal using simple existing measuring devices, avoiding the need for complex directional selective monitoring equipment.

Instead of continuous monitoring of system leakage capacitances, the patent uses periodic injection of measuring signals at resonant frequency. The fault detection is performed intermittently by injecting measuring signals and evaluating the resulting fault currents, rather than continuously monitoring capacitance ratios. This periodic approach maintains system stability while significantly reducing operational complexity and monitoring requirements.

The patent replaces the mechanical/electrical requirement of maintaining specific capacitance ratios with an electrical resonance-based detection method. Instead of physically ensuring proper capacitance distribution throughout the system, the invention uses frequency-based resonance to detect faults regardless of capacitance ratios. This substitution eliminates the need for continuous maintenance of capacitance ratios while preserving system stability.

The patent performs preliminary detection of high-resistance faults by injecting measuring signals before dangerous conditions develop. The resonant coupling circuit proactively seeks out faults by scanning for resonant responses, allowing detection and disconnection of faulty subsystems before they can cause electrical shocks or fires. This preliminary action maintains both operational continuity (by isolating only faulty portions) and safety (by detecting hidden dangers).

The patent introduces a measuring signal as an intermediary to detect high-resistance faults that would otherwise be undetectable. The resonant measuring signal acts as a mediator that interacts with the fault impedance to produce a detectable response. This intermediary approach allows safe detection of faults without requiring direct contact with potentially dangerous fault conditions, maintaining both safety and operational continuity.

The patent uses electrical resonance to amplify weak fault signals from high-resistance faults. By injecting a measuring signal at the resonant frequency of the fault path, even small fault currents are amplified significantly, enabling simple overcurrent protective devices to detect faults with high precision. The resonance effect transforms undetectable signals into strong, easily measurable signals without complicating the protective device itself.

The patent changes the frequency parameter of the measuring signal to match the resonant frequency of the fault path. This parameter change amplifies the fault current signal by factors of 10 or more, enabling simple protective devices to achieve high measurement precision. The frequency tuning transforms a signal too weak for simple devices to detect into a strong signal that can be reliably measured by conventional equipment.