为了研究两相体放电的基础问题,即放电特点、规律及影响因素,实验研究了聚丙烯、聚乙烯、珍珠岩3种典型固体颗粒的气固两相体电晕放电伏安特性。通过循环落体式两相体放电装置和测量系统观察发现,气固两相体的电晕电流特性与空气中的电晕电流特性有明显的区别。气固两相体的电晕电流波形在正、负极性下均为高频率脉冲波形。且在相同电压下其电晕电流比空气中的要小。固体颗粒的介电常数及在空气中所占的体积比均对电晕电流有很明显的影响。固体颗粒介电常数和体积比越大,电晕电流越小(可〈1μA)。电压极性的改变对气固两相体的电晕电流无影响。
The characteristic between direct voltage and corona current under discharge about two-phase mixture of gas and several kinds of solid particles is researched in this paper. The particles include polypropylene, polyethylene and perlite. In order to form a kind of two-phase mixture, a circulatory standard discharge device in two-phase mixture of which the diameter is 400cm was experimentally designed. The rod-plane type electrodes, made of copper, were chosen in the experiments. The diameter of the rod tip is 1mm, while the diameter of the plane is 30cm, and the gap is 15cm. Experimental results from the circulatory standard discharge device in two-phase mixture and measure system show that the characteristic of corona current in two-phase mixture of gas and solid is different from that in air. The waveform of corona current is pulse waveform with a high frequency. Under the same voltage, the corona current in two-phase mixture is lower than that in air. The volume ratio and permittivity of solid particles influence the corona current obviously. The corona current decreases when the volume ratio increases in the same solid particles-air mixture. The corona current also decreases when permittivity increases in the same volume ratio. The smallest current is lower than lirA. The diameter of particular also affects corona current. The corona current decreases when the diameter decreases under the same volume ratio and permittivity in the mixture. The polarity of voltage makes little effect on corona current. The results show that the difference of corona current is not obvious at positive and negative polarity when the same particular exists in same volume ratio.