MGVCL Exam Paper (30-07-2021 Shift 1)
A coil having an inductance of 100 mH is magnetically coupled to another coil having an inductance of 900 mH. The coefficient of coupling between the coils is 0.45. Calculate the equivalent inductance if the two coils are connected in series aiding.
Intern turn winding fault can be easily detect by differential protection relay. Also detect by buchholz relay (gas operated relay), cause buchholz relay is used to detect the internal fault of transformer.
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).