transformer active power

例句：

1. 1. The transformer is responsible for converting AC to DC power.
   变压器负责将交流电转换为直流电。
2. 2. The transformer is used in many electrical devices to convert voltage levels.
   变压器被广泛用于许多电气设备中，用于转换电压等级。
3. 3. The transformer was designed to improve the efficiency of the electrical system.
   变压器的设计旨在提高电力系统的效率。