Review of Electric Power Calculations

This chapter reviews some of the more important studies and calculations related to nuclear plant electrical systems. In general, the voltage drop calculations are performed with sophisticated computer programs, which take into account the plant loading conditions, the nature of the loads, and produce an output that includes the maximum and minimum loading, and the corresponding voltage drop. The voltage criteria, as established for the transmission power flow studies, should be used in the motor starting calculations to determine whether sufficient voltage is available during motor acceleration of the Class 1E loads. Motor starting calculations can be performed using dynamic simulation or static "snap shot" load flows. Dynamic motor starting analysis will provide more accurate results, but requires detailed information to develop dynamic models for various loads. The motor acceleration will depend on the net accelerating torque.