This is a new repetition penalty method that aims to affect token sequences rather than individual tokens.
For example, if you have a certain sentence that keeps appearing at different spots in your story, Phrase Repetition Penalty will make it harder for that sentence to complete.
The first token will generate, but the second token of the reoccurring sentence will get a penalty, then the third token will get a stronger penalty, and so on.
Phrase Repetition Penalty acts independently of the other repetition penalty settings. This means it won't be affected by any of the other repetition penalties' settings such as Rep Pen Range and Rep Pen Slope.
Phrase Repetition Penalty can still be used alongside the other repetition penalties, though, and they will all affect the output at the same time.
Another difference of this repetition penalty method, is that it doesn't have a slider. Instead, it has six settings of incrementing intensity for you to choose from: