You Do Need power plug adapter while traveling from Sudan to Greenland.

Here is Why You Need An Adapter

The outlet and plug type used in Greenland are C, E, F and K and in Sudan are C and D. This is how they look like.

Sudan

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

Type C

Type D

Greenland

In Greenland, outlets of type C, E, F and K are in use.

Type C

Type E

Type F

Type K