Inductor filter circuit

If the output voltage is still relatively stable when the load current is large, inductor filtering is used. The inductor filter circuit is shown in Figure 12-15. shown.
    We know that the DC impedance on the inductor coil
is very small, so the DC component in the pulsating voltage easily passes through the inductor coil and almost all reaches the load RL. The impedance of the inductor to AC is very large, so it is difficult for the AC component in the pulsating voltage to pass through the inductor coil . Since the inductor L and the load
R- are connected in series. The AC component can be viewed as a voltage divider if we choose the inductance x of the inductor. =It is much larger than the load RL (for example, the AC
power supply is 50Hz, the pulsation frequency after full-wave and bridge rectification is 100Hz, and the pulsation frequency after half-wave rectification is 50Hz). Then, most of the AC component will
drop on the inductor, and the load Ri. The communication component is very small. In this way, the original DC output with large pulsation becomes a relatively stable DC output
, as shown by the solid line in Figure b.
    If Ri.- is fixed, the larger the inductance, the smaller the output voltage fluctuation, and the better the filtering effect. Therefore, inductor filtering is generally suitable for
occasions with large load changes and large average load current.