Today we'll continue to introduce the work principle of power line filter-------CRC П type filter
Introduction to work principle
a. rectified output voltage is first filtered by C1 capacitor, most of the AC components are filtered, and the C1 voltage is added to the RC filter circuit made of RL and enough. Capacitor C2 further filter AC components.
b.C1 there is almost no inductance in the small capacitance, its capacitive reactance is very small, so the high frequency interference component is easily filtered to the ground through the small capacitance C1, and the high frequency AC interference filtering effect is better.
c. capacitance capacity is large (C2>C1), the low frequency AC component flows through the C2, and the filtering effect of low frequency AC interference is better.
d. resistance has voltage drop and power loss to AC and DC, so CRC is only suitable for small load current.