ARC DETECTION CIRCUIT, BREAKER SYSTEM, CONNECTION BOX SYSTEM, POWER CONDITIONER, MICRO INVERTER, DC OPTIMIZER, AND ARC DETECTION METHOD

摘要

This arc detection circuit (1) is provided with a current detector (2) and an arc determination unit (3). The current detector (2) detects a current flowing through a transmission path (8) which connects a power supply device and a power conversion circuit. The arc determination unit (3) determines the occurrence of an arc in the transmission path (8) by analyzing the current measurement result detected by the current detector (2) in terms of a frequency component, a time component, and a strength component. The arc determination unit (3) calculates, from the current measurement result, an area of interest (A1) which is the area of a range of interest (R) constituted from a prescribed frequency band (F) and a prescribed determination time (T), and a comparison area (A2) which is the area of a range that exceeds a prescribed strength threshold in the range of interest (R). In addition, when the area ratio (A2/A1) of the area of interest (A1) and the comparison area (A2) exceeds a prescribed area ratio threshold (L), an arc is determined to have occurred.