Electrical Machines – I

Week 1: Single phase Ideal transformer and basic equations. Its equivalent circuit. Week 2: Core loss: Eddy current and hysteresis loss – factors on which it depends. Week 3: Taking Leakage flux, winding resistances and core loss in the equivalent circuit of the transformer. Week 4: Exact and approximate equivalent circuit. Phasor diagram. Regulation & efficiency. Week 5: Open circuit and short circuit tests. Estimation of equivalent circuit parameters. Week 6: Three phase transformer and various connections with vector groups. Week 7: DC machine constructional features and basic idea of its operation. Armature winding, commutator segments and brushes. Week 8: Lap and wave windings and number of parallel paths in armature circuit. Emf equation. Week 9: Torque equation. Separately excited and shunt generator characteristics. Week 10: Armature reaction and its ill effects. How to nullify the effects of armature reaction. Week 11: Shunt, series and compound motor characteristic. Week 12: Starting, speed control and braking of DC motor. Testing.