... current, voltage, and flux linkage are expressed respectively in volts, amperes, and volt-seconds.For AC machines, the torque and speed can be also expressed in pu. The following base quantities ... Units?What Is the Per Unit System?The per unit system is widely used in the power system industry to express values of voltages, currents, powers, andimpedances of various power equipment. It is mainly ... in kg*m , you would generally give the inertia constant H defined asThe inertia constant is expressed in seconds. For large machines, this constant is around 3 to 5 seconds. An inertiaconstant...