PARALLEL ARC DETECTION USING DISCRETE WAVELET TRANSFORM

• Main Authors: HALL SCOTT JEFFREY, CHANGALI SRIRAM, GRIGORYAN KONSTANTIN V, HOOKER JOHN KENNETH
• Format: Patent
• Language: English
• Published: 22.07.2010
• Subjects: CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS; GENERATION; MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; TESTING

PROBLEM TO BE SOLVED: To provide an apparatus that performs parallel arc fault current interruption (AFCI). SOLUTION: The apparatus includes a current sensing device, disposed in an electrical circuit to sense an electrical load and generate an output signal, indicating a load current passing through the current sensing device itself and a detection unit, configured and disposed to receive the output signal generated by the current sensing device and output a secondary signal, based on the output signal, and a microcontroller connected with the detection unit to respond to a computer-executable instruction. According to the computer-executable instruction, the microcontroller receives the secondary signal and decomposes the secondary signal by using discrete wavelet transform. The microcomputer generates a trip signal, when it is found that discrete wavelet coefficients are obtained; a sum of the coefficients is calculated; the sum of the coefficients is compared with a predetermined threshold, the detected load current exceeds a predetermined threshold; and the sum of the coefficients cooperatively meets the predetermined threshold conditions for trip signal generation. COPYRIGHT: (C)2010,JPO&INPIT