You Do Need power plug adapter while traveling from Iraq to Papua New Guinea.

Here is Why You Need An Adapter

The outlet and plug type used in Papua New Guinea is I and in Iraq are C, D and G. This is how they look like.

Iraq

In Iraq, outlets of type C, D and G are in use.

Type C

Type D

Type G

Papua New Guinea

In Papua New Guinea, outlets of type I are in use.

Type I