You Do Need power plug adapter while traveling from South Sudan to New Caledonia.

Here is Why You Need An Adapter

The outlet and plug type used in New Caledonia are C and F and in South Sudan are C and D. This is how they look like.

South Sudan

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

Type C

Type D

New Caledonia

In New Caledonia, outlets of type C and F are in use.

Type C

Type F