Multifunctional（poly（diallyldimethyl ammonium chloride）/sodium poly（4-styrene sulfonate）） n（（PDDA/PSS） n） thin films were fabricated by layer-by-layer assembled on the glass substrate.The monolayer silica na...Multifunctional（poly（diallyldimethyl ammonium chloride）/sodium poly（4-styrene sulfonate）） n（（PDDA/PSS） n） thin films were fabricated by layer-by-layer assembled on the glass substrate.The monolayer silica nanoparticles were prepared on the（PDDA/PSS） n films.The SiO 2-polyelectrolyte coatings exhibit antireflection properties with low refractive index（as low as 1.22）.Interestingly,wavelengths of maximum transmittance could be well tailored by simply changing the particle size of SiO 2.A maximum transmittance of 97.03% in the visible spectral range is achieved for the particle size of 100 nm SiO 2 films.The coatings also show excellent mechanical stability and good adhesion to substrates.The easy availability of the raw materials and simplicity of the fabrication method for such films might make them be potentially useful for various applications.展开更多
针对当前的有源消弧方法因谐波电流检测精度不足而效果较差,以及传统消弧线圈在谐波影响下容易导致消弧失败的问题,设计了一种无须谐波检测便可有效抑制故障点残流中谐波分量的新型消弧线圈。该消弧线圈由逆变器并联传统消弧线圈构成,...针对当前的有源消弧方法因谐波电流检测精度不足而效果较差,以及传统消弧线圈在谐波影响下容易导致消弧失败的问题,设计了一种无须谐波检测便可有效抑制故障点残流中谐波分量的新型消弧线圈。该消弧线圈由逆变器并联传统消弧线圈构成,其中逆变器的指令电压根据中性点电位进行调整,可使逆变器支路不产生基波电流;逆变器的低谐波阻抗特性可有效降低故障点残流中的谐波分量;同时传统消弧线圈过补偿可抵消电容电流。经过Matlab和PSCAD/EMTDC(power systems computer aided design/electromagnetic transients including direct current)仿真,结果显示新型消弧线圈将故障点处的5次谐波、7次谐波分别由25.62、65.85 A降低到了0.11、0.57 A,能够实现可靠消弧。该研究在配电网消弧领域具有一定的应用前景。展开更多
基金Supported by the National Science Foundation of China(21174108)the Fundamental Research Funds for the Central Universities(20102020201000017)
文摘Multifunctional（poly（diallyldimethyl ammonium chloride）/sodium poly（4-styrene sulfonate）） n（（PDDA/PSS） n） thin films were fabricated by layer-by-layer assembled on the glass substrate.The monolayer silica nanoparticles were prepared on the（PDDA/PSS） n films.The SiO 2-polyelectrolyte coatings exhibit antireflection properties with low refractive index（as low as 1.22）.Interestingly,wavelengths of maximum transmittance could be well tailored by simply changing the particle size of SiO 2.A maximum transmittance of 97.03% in the visible spectral range is achieved for the particle size of 100 nm SiO 2 films.The coatings also show excellent mechanical stability and good adhesion to substrates.The easy availability of the raw materials and simplicity of the fabrication method for such films might make them be potentially useful for various applications.
文摘针对当前的有源消弧方法因谐波电流检测精度不足而效果较差,以及传统消弧线圈在谐波影响下容易导致消弧失败的问题,设计了一种无须谐波检测便可有效抑制故障点残流中谐波分量的新型消弧线圈。该消弧线圈由逆变器并联传统消弧线圈构成,其中逆变器的指令电压根据中性点电位进行调整,可使逆变器支路不产生基波电流;逆变器的低谐波阻抗特性可有效降低故障点残流中的谐波分量;同时传统消弧线圈过补偿可抵消电容电流。经过Matlab和PSCAD/EMTDC(power systems computer aided design/electromagnetic transients including direct current)仿真,结果显示新型消弧线圈将故障点处的5次谐波、7次谐波分别由25.62、65.85 A降低到了0.11、0.57 A,能够实现可靠消弧。该研究在配电网消弧领域具有一定的应用前景。
