A grid-interactive photovoltaic (PV) system uses solar energy to generate renewable power that charges batteries for use during power failures and feeds power into the electricity grid.
Grid-interactive systems are based on their grid-tied and off-grid counterparts.
Maximum permissible load = Rated MVA rating*fraction of rated kVA
Maximum permissible load = 15*1.25
Maximum permissible load = 18.75 MVA
The magnitude of earth fault current for a given fault position within a winding demands upon the winding connections and method of neutral grounding.
Earth fault protection for an electric motor is provide by instantaneous relay having a setting of approximately 30% of motor rated current in the residual circuits of two CTs and with ground wire.
Rotor frequency, f_r = s*f_s
s = 2/50
s = 0.04
Ns = 120f/P
Ns = 1500 rpm
s = (Ns - Nr)/Ns
Nr = Ns(1 - s)
Nr = 1500*(1 - 0.04)
Nr = 1440 rpm