The first two are used if you are asking the person directly.
The third is mainly used if you are asking someone else about Philippe, but it is more or less not the best formulation.
The fourth could be used in both cases.
Two more ways could be used if you are talking to Philippe directly.
Or in an inquisitive tone:
All but the third one are correct French, but none of them is asking a person's name.
1 and 2 are asking someone if he is Philippe (and not someone else). (Are you Philippe?) Alternatives are C'est vous, Philippe ?
4 is asking someone if someone else is Philippe. (Is he Philippe?)
To ask someone if his name is Philippe, you might say:
(Est-ce que) vous vous ...