Exegesis:

egō gar egnōn dunamin exelēluthuian ap’ emou ‘for I perceived that power had gone out from me.’ For the meaning of egnōn. The perfect tense of exelēluthuian does not refer to an event preceding that of the main verb but points to an accomplished situation.

Translation:

Some one touched me, or better to mark the clause as a refutation, ‘no, some one did touch me.’ The verb, again, expresses an intentional act, whereas unintentional touching was implied in Peter’s remark.

I perceive, or, ‘I know/feel,’ ‘I am aware.’

That power has gone forth from me. If ‘power’ has to be possessed in this context, one may say, ‘some power of mine,’ ‘part of my power.’ The healing is probably not to be envisaged as an intentional act on Jesus’ part.

Quoted with permission from Reiling, J. and Swellengrebel, J.L. A Handbook on the Gospel of Luke. (UBS Handbook Series). New York: UBS, 1971. For this and other handbooks for translators see here . Make sure to also consult the Handbook on the Gospel of Mark for parallel or similar verses.