I am designing a 2800W telecom rectifier & using UCC3854 PFC controller. The input range of the rectifier is 90-300V AC. The specification calls for less than 10% ITHD over the entire range when the rectifier is supplying half to full load. With months of experimentation & iterations I have not achieved this ITHD figure beyond 270V input. I have used two CT's for current sensing, one for switch current & another for diode current. I sought help from local TI rep. but the problem still remains unsolved. Please help.
Thanks.