摘要：影响噪声烦恼的声学参量较多,然而在传统噪声控制工程中,往往仅根据A计权声压级所需降低量进行控制方案设计,未能从烦恼改善程度优选方案.为此,本研究提出一种基于烦恼改善程度优选噪声控制方案的方法,并将该方法应用于变电站声屏障噪声控制方案的比选.结果表明,同一声屏障方案对不同关心点噪声烦恼的改善程度差异较大,A计权声压级降低量最大的声屏障方案对噪声烦恼的改善效果未必最好.因此,噪声控制工程设计中,宜根据所关心的声环境保护目标与噪声源的相对位置,选取对保护目标处噪声烦恼改善程度较大的方案.

摘要：A novel 50 kW fast charger was proposed for electric vehicles. The proposed fast charger is divided into two main sections an AC-DC converter performing a PFC function and a DC-DC converter performing a charging function. A transformer including leakage inductances was used in the AC-DC converter in order to obtain isolation and inductance. A series-connection topology was used in the DC-DC converter between the DC-bus and outlet. This topology enables high power conversion efficiency up to 95% for the DC-DC converter. In order to reduce the impact of the 50 kW charging on the AC grid, the proposed fast charger system includes a buffering battery unit between the two main power conversion units. This leads to reductions in the power installation costs of power companies and to improvements in the power quality were verified through simulations and experimental results. on the AC grid. The performances of the proposed fast charger system