MGVCL Exam Paper (30-07-2021 Shift 1)
A transformer designed for operation at 60 Hz supply is working at 50 Hz supply system without changing its voltage and current ratings. Compared to the full load efficiency at 60 Hz, the full load transformer efficiency at 50 Hz.
The V-curves of a synchronous motor show relationship between Armature current (Ia) and Excitation current (If). The Inverted V-curves of a synchronous motor show relationship between power factor (pf) and field excitation (If).