Exercise 1

An AC signal source of 5 V is connected to a resistive load through two parallel conductors separated by air as shown. The copper conductors have diameter of 5 mm and length of . The centre-to-centre spacing between conductors is 20 mm. Electrical properties of copper: and , respectively. Determine the voltage across the load at 50Hz and 5MHz.

Solution

计算趋肤深度

根据Skin Effect的表达式:

根据给定的数据,可以计算得到:

fd
50Hz9.35mm
5Mhz

计算导线电阻

由于导线的直径为5mm,所以50Hz时趋肤深度大于半径2.5mm。带入电阻的计算公式: 在5MHz时需要考虑趋肤效应:

计算导线电感

50Hz时需要考虑导线的自感:

5MHz时不需要考虑线材的自感: