Effect of nanoparticles on impulse breakdown performance of propylene carbonate based on modified Kerr electro-optic measurements

Impulse breakdown test results show the breakdown strengths of propylene carbonate modified by Al
₂
O
₃
nanoparticles and Fe
₃
O
₄
nanoparticles are improved by 13% and 20% than that of propylene carbonate without nano-modification, respectively. In order to explore the nano-modification mechanism, the electric field and space charge distributions in propylene carbonate with and without nano-modification were measured through a modified Kerr electro-optic measurement method. The measurement results show the space charge densities are decreased and the space charge transportations are inhibited in PC-based nanofluids compared with that of pure propylene carbonate due to the space charge adsorption of nanoparticle. Therefore, the streamer propagation in nanofluids is impeded, and the breakdown voltage is improved. The calculation of electric potential outside the nanoparticle indicates that Fe
₃
O
₄
nanoparticle has stronger space charge adsorption capacity than Al
₂
O
₃
nanoparticle. Accordingly, the Fe
₃
O
₄
-modified propylene carbonate shows greater improvement of breakdown performance than Al
₂
O
₃
-modified propylene carbonate.