Arc Detection Circuit Using Frequency Characteristic Comparison

The patent transitions from one-dimensional detection (voltage and current magnitude only) to two-dimensional detection by incorporating frequency characteristics. The arc detection device analyzes both the magnitude and frequency spectrum of current, enabling differentiation between arc events and noise based on their distinct frequency signatures. This dimensional expansion resolves the contradiction by maintaining relative simplicity while significantly improving detection accuracy.

The patent changes the detection parameter from simple voltage/current magnitude to frequency characteristics of current. By performing Fourier transformation on the detected current and analyzing frequency spectrum changes, the system can identify arc events through their characteristic frequency patterns. This parameter transformation enables accurate arc detection while keeping the device structure relatively simple.

The patent makes the existing current detector perform multiple functions: it not only detects current magnitude but also provides input for frequency spectrum analysis. By integrating the Fourier transformation unit and frequency characteristic analysis into the existing detection framework, the system achieves enhanced arc detection capability without adding completely separate detection subsystems, thereby limiting the increase in device complexity.

The patent introduces a Fourier transformation unit as an intermediary that processes the detected current signal to extract frequency characteristics. This intermediary component bridges the simple current detection and the complex arc identification, enabling frequency-based arc detection while maintaining a modular architecture that limits overall system complexity.

The patent replaces the purely mechanical/electrical switch tripping mechanism with an intelligent detection and control system. Instead of relying solely on current magnitude to trigger switch tripping, the system uses frequency characteristic analysis to detect arcs and sends control signals to the switch. This substitution enables the switch to trip even when arc current is small, as the decision to trip is based on frequency-based arc identification rather than current threshold alone.

The patent implements a feedback control system where the arc detection device continuously monitors frequency characteristics, compares them against reference values, and sends appropriate control signals to the switch based on arc detection results. This feedback mechanism enables sensitive arc detection and appropriate switch tripping decisions, resolving the issue of switches failing to trip during low-current arc events.