SMPS Feedback Concept and Problem

[hamid159]

Hy Guyz,
i've made some SMPS.but due to improper feedback they are not working properly..i.e. not regulated.Voltage drops on load.Please can anyone make my concept on feedback.Is there any book ( open source ) on SMPS feedback?Recently i've made a power supply using uc2875 ( full bridge configuration ).Ground of 12V ( vcc of uc2875 ) and output ground are connected to each other.but is isolating from ground of 310V.How i can implement feedback so that even at high load there is no voltage drop.
Any help would be appreciated.

 

[--BawA--]

To implement the feedback there are two methods basically , 1st method is to use error amplifier and control the dutycycle of PWM accordingly.
2nd method is to implement PID controller in any suitable microcontroller or DSC.
and i think you should use any pwm dedicated ic such as sg3525. you can easily implement feedback in it because it incorporates error amplifier stage.