How does matlab simulink (simpower system)calculates this from machine parameters?

how does it know these parameters?

Answer 1

[Sebastian Castro]

The per unit system is based on the nominal Voltage, Power, and Frequency which is specified in the Parameters tab of that block.

Look at this example, for instance: http://www.mathworks.com/help/physmod/sps/ug/per-unit-system-of-units.html#btzx9ky-3

- Sebastian