Capacitors have no voltage regulator function! Its role in the power filter circuit is to store energy to increase the effective value of DC voltage and filter out the residual AC components! And voltage regulation are two concepts! Voltage regulation is achieved by voltage regulator diode or scatter tube and voltage regulator integrated circuit circuit!
The output of the rectifier circuit is not the real DC voltage! It is a unidirectional pulsating voltage composed of half waves in one direction! It not only has the intensity change of the jump! Also contains residual AC and harmonic components! This kind of DC power supply is not able to make the precision electronic circuit work properly!
We know that the characteristic of capacitors is that they can hold a lot of charge! And it can release! At the same time, it is the release of alternating current!
We connect enough capacitors to both ends of the rectifier output! That's where its charging and storage comes in handy! First of all, it is to pull the unidirectional wave pulsating voltage at the output end to a voltage value that is approximately flat and smooth! It also enhances the current load performance of the power output! What's more, it can also loop the remaining AC and harmonic components in the power supply into the ground! That's what capacitors do in power filters!