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为深入探究硅橡胶电晕老化后的表面电荷变化及其对沿面闪络的影响，首先通过多针–板电极对硅橡胶试样进行电晕老化。通过测量不同老化时间下硅橡胶的表面电荷分布以及一定老化时间下硅橡胶在外加电压为零至闪络过程中的表面电荷分布，探究了硅橡胶在不同老化阶段的表面电荷变化以及电晕老化后硅橡胶的沿面闪络。最后通过热刺激电流试验、扫描电镜和傅里叶变换红外光谱分析方法研究试样在电晕老化过程中微观电特性与物化缺陷的变化，并讨论了电晕老化后硅橡胶的陷阱特性对其表面电荷的影响。研究结果表明：随着电晕老化时间的增加，硅橡胶的陷阱能级加深、陷阱电荷量增加，同时硅橡胶表面俘获载流子能力增强、表面电荷增多；随着外加电压的提高，硅橡胶的表面电荷最大值逐渐向两电极间距离最小处移动，直至局部放电贯穿两电极，发生闪络。因此可知，随着电晕老化时间的增加硅橡胶的表面带电能力增强，表面电荷引发的局部放电更剧烈，是导致硅橡胶闪络电压降低的原因。“,”To deeply investigate the influence of corona aging on surface flashover and surface charge of silicone rubber, Silicone rubber was aged by multi-needle-plate electrodes at different aging time. By measuring the surface charge of aged silicone rubber at different aging time and from zero voltage to flashover, the change of surface charge and surface flashover of aged silicone rubber were studied. At last, in order to investigate the influence of the trap characteristics on the surface charge of silicone rubber, thermal stimulation current (TSC), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) tests were used to observe the change of micro electrical properties, physical and chemical defects of the samples at different aging time. According to the tests results, with the increase of corona aging time, the trap level of silicone rubber goes deep, trap charge increases and the capacity of silicone to capture charge gets enhanced which causes the raise of surface charge. It can also be known that with the increase of voltage level, the maximum of surface charge gradually approaches the nearest area between two electrodes until partial discharge gets through the two electrodes and results in surface flashover. In conclusion, with the increase of corona aging time, the capacity of silicone rubber to catch charge gets enhanced which causes a stronger partial discharge is the reason for the decrease of flashover voltage.