【摘要】 在直流电场作用下 ,用电声脉冲法测量了低密度聚乙烯 (LDPE)中空间电荷的分布 ,计算结果表明 ,异极性空间电荷严重畸变试样中的电场的分布。以少量氯化聚乙烯 (CPE)混入低密度聚乙烯中 ,大大降低了试样中的空间电荷 ,电场分布趋向均匀。在正负极性直流预压短路树枝试验中 ,分别提高试样短路树枝起始电压 2 6 8%和 36 3%。通过直流预压和电晕电荷注入后 ,短路过程中空间电荷分布的测量 ,提出氯化聚乙烯的作用机理在于降低了聚乙烯中陷阱的深度和密度。更多还原

【Abstract】 The practical distribution of space charges in low density polyethylene(LDPE)under dc electrical field is measured by electro-acoustic pulse(PEA)method.It is show by calculation that the electrical field in samples is seriously distorted by heteropolar space charges.To blend a small amount of chlorinated polyethylene(CPE)into polyethylene,the space charges in samples are greatly decreased and the field distribution trends to uniform.The initiation voltage of short circuit treeing after the positive and the negative dc pre-stress increase by 26 8% and 36 3% respectively.With the measurements of space charges duing the short circuit process after dc pre-stress and injection of corona charge,it is suggested that the mechanism of chlorinated polyethylene lays to decreasing the depth and density of traps.更多还原