Research and Implementation of Low Cost Arc Fault Circuit Interrupter

Abstract

With the increasing of residential electricity and electrical fire accidents increasingly serious also, fault arc as one of the important causes of electric fire accident has aroused extensive attentions. The conventional breakers or protection device are unable to provide comprehensive protection of arc fault. And now a special apparatus named AFCI (Arc Fault Circuit Interrupter) has been proposed. But the performance of the AFCI needs improvement, so the study of arc fault characteristic to propose arc fault diagnosis method has important significance. In the paper, an arc fault experiment platform is set up so as to acquire the arc fault data. Then FFT is applied to analysis the frequency characteristics of the arc fault current. Result proved that the appearance of arc fault lead to the increase of the harmonic order. An arc fault detection technique based on the grid fractal theory is proposed in the paper. By analysis the change rate of circuit current, the arc fault can be diagnosis. As the arc fault is difficult to diagnosis, the cost of the conventional arc fault circuit breaker developed before is very high. While in the paper, a low cost AFCI based on the technique for low voltage distribution system is introduced. The hardware and the software of the AFCI are present in the paper. After test, the results show that the device has a good performance in arc fault protection. And it is suitable for electrical fire protection