MATLAB: PI controller for boost converter design

Question

hello everyone…. I am doing a project on powerfactor correction using boost converter i need to design a pi controller to control the duty cycle switch. when give reference input to PI controller and while tuning it is showing your model linearizes to zero then i am not able to tune it.

i given output of bridge rectifier to boost converter output i am using average current mode control

it is showing the following error " The plant model in the PID loop linearizes to zero, and therefore cannot be used in PID controller design. This problem occurs when one or more blocks in the PID loop have zero gain or the feedback loop is not physically closed. Click "Continue" to launch the PID Tuner and obtain a new plant model in the "Obtain plant model" dialog. Click "Cancel" to abort PID design and return to the block dialog. For more information, see the Simulink Control Design documentation".

help me please……thanks in advance……

Answer 1

Update as of April 2014: his has now been addressed in R2014a, please take a look at this video and this example .

People typically run into this situation when they have pwm or some other type of high frequency switching in their model.

You can try to modify your model to not have high-frequency switching (use averaging mode). Please take a look at this webinar, it should be helpful.

Another option is to use frequency response estimation together with system identification approach. This demo should be very close to what you are trying to do.

HTH.

Arkadiy