Would there be an action potential, if during repolarization there is an increase of membrane potential to the threshold level using the current clamp?

I'm not sure I understand what you mean by "current clamp", but the general answer is no.

To explain - sodium channels actually have three states: open, closed and inactive (may go by different names depending on where you look).

Summation can be performed during depolarisation phase.but during repolarisation sodium channels are in inactivated state not closed , in skeletal muscle .
So no untill a bare minimum time ,it can't be done .but in relative refractory period it