Waveform characteristics of voltage and current in coal fracturing process based on electrical fragmentation 煤体电破碎过程中的电压与电流波形特性

The typical voltage and current waveforms in the process of electrical fragmentation were studied by the self-built coal electrical breaking experimental system for the investigation of the variation mechanism of voltage and current. By testing the influence of coal sample thickness on voltage and current in the process of electrical fragmentation, the relationship between peak current, breakdown delay, instantaneous power and coal sample thickness was investigated. The relationship between deposited energy and time and the relationship between energy conversion rate and the thickness of coal sample were discussed. The results indicate that under the same breakdown voltage, the peak current is inversely proportional to the thickness of coal sample, while the electrical breakdown delay increases with the increase of the thickness of coal sample, but the instantaneous power has no obvious relationship with the thickness of coal sample. The thickness of coal sample has a significant effect on deposited energy. The deposited energy increases rapidly in the initial stage, then slows down gradually, and finally tends to be stable. There is an optimal energy conversion efficiency under the same breakdown voltage.