不同类型电源激励下HMDSO添加比例对Ar介质阻挡放电特性的影响

Wet flashover and pollution flashover on the surface of insulation material will bring hidden dangers to the safety of power systems. Hydrophobic modification with low-temperature plasma can reduce the wetting of water on the surface of the insulation material, inhibit the adsorption of dirt and dust, and improve its resistance to flashover such as wet flashover and pollution flashover. To achieve this goal, hydrophobic precursor can be added to the discharge gas, and hydrophobic groups can be introduced on the surface of the material to improve the hydrophobicity. In this paper, hexamethyldisiloxane (HMDSO) is added as hydrophobic precursor in Ar dielectric barrier discharge (DBD), and influences of HMDSO addition ratio on optical and electrical discharge characteristics are studied under high frequency, microsecond pulse and nanosecond pulse power source, respectively. Results show that DBD driven by different power sources all present filamentary discharge mode, and bright discharge filaments appear driven by nanosecond pulse source. The discharge uniformity is improved due to the addition of HMDSO. Driven by high frequency and microsecond pulse power source, the addition of HMDSO causes the discharge current and the emission spectrum intensity to decrease. The discharge current and emission spectrum intensity first increase and then decrease excited by nanosecond pulse power source. When the addition ratio is 1. 5%, the discharge current and emission spectrum are the largest. The equivalent circuit model is used to calculate the corresponding discharge energy efficiency. The efficiency of high frequency DBD is the lowest, about 20%, and the efficiency of nanosecond pulse DBD is the highest, about 70%. The addition of HMDSO has no obvious effect on the efficiency. Comparing three types of power sources, the nanosecond pulse power source has the largest discharge intensity and energy efficiency, and has stronger ability to generate active particles with proper HMDSO ratio, which can provide more favorable conditions for hydrophobic modification.