Speaking after the match, Powell described the competition as "wonderful".
"The FA Cup is a wonderful competition and we're delighted to get through. It's been much maligned at times, which I think is a disgrace, because it's one of the best," Powell is quoted as saying on TheFA.com.
"Now, it comes alive in the later rounds and we didn't want to be a casualty, which we were close to being last week. But we've come through it and now I want us to go to Huddersfield and get through that game."
Charlton travel to face the Terriers on Saturday.