His complete name was Niels Hansen Pors. He was born with the name Niels Hansen (without Pors).
 
The name Pors once was a noble family's name. But the noble family was long time extinct. In that time they only cared about the male side of the family.
 
Niels Hansen Pors was awarded the name Pors. This was done of the Danish king in 1771/1772. So the now living Pors's family/persons descend from this Niels Hansen Pors.

I know about older Pors's too, but I have no connections between them and the now living Pors's. Not yet.
I don't know why Niels Hansen was given the name Pors. But I guess he was related to the older families Pors on the female side. But this is just a guess.

Niels Hansen Pors was a parish clark. In Swedish his title was "klockare". That is the same word as English "clock". I.e. he was the man who among other things was responsible for the church clock (church bell). Often this person at the same time was some kind of teacher. Niels' father, his father's father and his father's father's father also were parish clerks (klockare).