UC28180_Power Factor Correction IC

gopal krishnan1

Other Parts Discussed in Thread: UCC28180

Hi,

I am using UC28180 power factor correction IC along with UC28600 QR controller. The maximum power output of the converter is 25 watts. Since this design for aerospace, it is required to meet the leading PF more than 0.98 as well as the individual harmonics requirement.

I am finding difficulty in reducing 3rd harmonic as well as some of the higher frequency harmonics.

Attached the current waveform and current harmonic waveform. It is observed there there is some ringing at the zero crossing. I would like to know how I can remove these ringing as well as improve the PF.

Waveform attached with issue area highlighted.

Regards

over 11 years ago

0 Yunsheng Qu over 11 years ago

TI__Genius 9790 points

hi, krishnan

for aerospace application, the input frequency is 400Hz, right? what the switch frequency is?

i attached a calculator of UCC28180 for your reference.

for 3rd harmonic, the voltage loop compenstator is very important, so please calculate the R/C value connected to COMP pin.

and UCC28180 is good at THD/PF, the Cap connect to ICOMP is very important.1323.UCC28180 Design Calculator_SLUC506.xls

0 gopal krishnan1 over 11 years ago

Prodigy 70 points

Hi,

The input frequency is 340Hz to 800Hz. PFC switching frequency is 66kHz . This IC have variable frequency option. So, if I select higher frequency, can I expect any improvement in the harmonics?

Btw, how can I reduce the ringing observed at the zero crossing point?

Thanks and regards

Gopal

0 Yunsheng Qu over 11 years ago in reply to gopal krishnan1

TI__Genius 9790 points

Hi, Gopal

You can try to improve switch frquency to 120kHz.

please tune the RC compensator connect to VCOMP pin.

and tune the Cap value connect to ICOMP pin.

regards,

Yunsheng

0 gopal krishnan1 over 11 years ago in reply to Yunsheng Qu

Prodigy 70 points

Hi Yunsheng,

I have tried to optimise the Icomp capacitor and observed that it is reducing at 400Hz, But increasing at 800Hz. So I am interested to know the relationship between the harmonic component and the loop cross over frequency . Is any suggestions?

Best regards,

Gopal

Power management

Power management forum

UC28180_Power Factor Correction IC