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

Here is Why You Need An Adapter

The outlet and plug type used in South Sudan are C and D and in Peru are A, B and C. This is how they look like.

Peru

In Peru, outlets of type A, B and C are in use.

Type A

Type B

Type C

South Sudan

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

Type C

Type D