Single Phase Transformer
Subject and UNIT: Electrical Machines: Unit IV: Single Phase Transformer
• Consider an ideal transformer on no load as shown in the Fig. 6.6.1. The supply voltage is V1 and as it is an no load the secondary current I2 = 0.
Subject and UNIT: Electrical Machines: Unit IV: Single Phase Transformer
• When the primary winding is excited by an alternating voltage V1, it circulates alternating current, producing an alternating flux ϕ.
Subject and UNIT: Electrical Machines: Unit IV: Single Phase Transformer
The various constructions used for the single phase transformers are, 1. Core type 2. Shell type and 3. Berry type
Subject and UNIT: Electrical Machines: Unit IV: Single Phase Transformer
The various parts of transformer are,
Subject and UNIT: Electrical Machines: Unit IV: Single Phase Transformer
The principle of mutual induction states that when two coils are inductively coupled and if current in one coil is changed uniformly then an e.m.f. gets induced in the other coil.
Single Phase Transformer
Subject and UNIT: Electrical Machines: Unit IV: Single Phase Transformer
• The main advantage of alternating currents over direct currents is that, the alternating currents can be easily transferable from low voltage to high or high voltage to low.
Electrical Machines
Subject and UNIT: Electrical Machines: Unit IV: Single Phase Transformer
Electrical Machines: Unit IV: Single Phase Transformer : Syllabus, Contents
Testing of D.C. Machines | Electrical Machines
Subject and UNIT: Electrical Machines: Unit III: b.Testing of D.C. Machines
Electrical Machines: Unit III: b.Testing of D.C. Machines : Two Marks Questions with Answers
DC Machines
Subject and UNIT: Electrical Machines: Unit III: b.Testing of D.C. Machines
The two components of iron losses are eddy current losses and hysteresis losses. While other no load losses are friction and windage losses.
Solved Example Problems | Testing of D.C. Machines
Subject and UNIT: Electrical Machines: Unit III: b.Testing of D.C. Machines
This is one of the methods of testing the d.c. series motors. Unlike shunt motors, the series motor cannot be tested by the methods which are available for shunt motors as it is impossible to run the motor no load.
Advantages, Disadvantages, Solved Example Problems | Testing of D.C. Machines
Subject and UNIT: Electrical Machines: Unit III: b.Testing of D.C. Machines
• This test is called regenerative test or back to back test which can be carried out on two identical d.c. machines mechanically coupled to each other and simultaneously tested.
Testing of D.C. Machines
Subject and UNIT: Electrical Machines: Unit III: b.Testing of D.C. Machines
• This method is generally employed to shunt generators and shunt motors. From this method we can get stray losses. Thus if armature and shunt copper losses at any given load current are known then efficiency of a machine can be easily estimated.