Introduction to filter Work Principle II

Today we'll continue to introduce the work principle of power line filter-------DLC type filter

1. Introduction to work principle

a. when the secondary winding of the transformer is positive and negative, as the output voltage of the secondary winding of the transformer is a positive and negative alternating rectangular wave, the D1 rectifier is added to remove the negative half cycle. After the positive half cycle passes through the D1 rectifier, the current is stored and stored through the inductor L.

b. when the input positive pulse disappears, the self-inductive voltage generated by the secondary winding of the transformer is positive and negative, so the rectifier D1 cut-off, the filter has no input voltage, and the current supply RL the load consists of two parts. The current direction is the same as the current direction iL, and the current provided by C1 discharge is ic1..

2. DLC filter, the output DC voltage is the average value of its input rectangular wave voltage.

3. DLC type filter is commonly used in pulse width switching power supply, the output end of the DLC, need to parallel a resistance to the ground, commonly called "release resistance ", generally in the release resistance 30-50 mA.