【摘要】 介绍了重复频率快脉冲下固/液体介质交接面闪络初步的实验结果。脉冲功率源为基于半导体断路开关(SOS)的SPG200,固体介质为有机玻璃和尼龙,液体介质为变压器油。在相对低频阶段,闪络耐压时间与闪络场强随外加电压脉冲频率的增加非线性迅速减小,在约200 Hz以后,两者下降的趋势明显减缓。随着脉冲频率的增加,闪络耐压时间在统计上变小的同时,在一定区间内的分布也更均匀。分析表明,在不同实验条件下,重复频率显著低于单次下的沿面闪络和体击穿场强,两类场强都随脉冲频率增加非线性下降,在约200 Hz以后,下降的程度减弱。闪络场强随重复频率电压脉冲频率的变化表明,电压作用时间是绝缘介质击穿的根本要素,脉冲电压对绝缘介质的作用时间越长,沿面闪络越容易发生。更多还原

【Abstract】 The primary experimental results of surface flashover over interfaces of polymethyl methacrylate(PMMA)/transformer oil and nylon1010/transformer oil under repetitive frequency short pulse(RFP) are introduced.The pulsed power source is SPG200 based on SOS,and solid dielectrics are polymethyl methacrylate and nylon,and liquid dielectric is transformer oil.Both flashover stressing time and flashover field strength decrease rapidly and nonlinearly with the increase of frequency of applied pulse voltage,and the decline slowers in evidence when the frequency exceeds about 200 Hz.At the same time,the flashover stressing time has more uniform distribution in a certain range with the increase of applied pulse frequency.It is inferred that the flashover and breakdown field strengths under RFP are markedly lower than those under single pulse in different experimental conditions,and they both descend rapidly at low pulse frequency,followed by a slower decline at the frequency higher than 200 Hz.The relationship between flashover field strength and repetitive pulse frequency shows that the longer the insulating dielectrics are stressed by RFP,the easier the surface flashover occurs i.e.stressing time is the decisive factor of inducing flashover.更多还原