千瓦－小时电功率的单位，等于在一千瓦功率下一小时内消耗的功
A unit of electric power equal to the work done by one kilowatt acting for one hour.
总之，功不包括时间，而功率包括时间。
In any case work does not include time, but power does.
输出功率绝不能等于输入功率，因为总存在着损耗。
The output power can never equal the input power, for there are always losses.
