New definition formulas for apparent power and active current of three-phase power system

A new definition formula for apparent power of the three-phase system is justificated. It is the average geometric value of the currents power losses and short circuit power of the voltage source loaded by transmission line resistances. The Buchholz's apparent power formula follows from this definition as a special case if both zero sequence components of currents and voltages are nil. Under unbalanced voltage the meaning of apparent power in accordance with proposed formula may exceed Buchholz's one more than on 10%. The generalized definition formula for introduced by Professor Fryze concept of power system's active current is grounded. It is part of the short-circuit current that is equal to ratio between load power and short-circuit power of the voltage source. In such way specified active current provides up to 15% power losses gain in the transmission line compared to the original Fryze's definition in the presence of voltage zero-sequence component.