Exam

Practical lab report

1 Single-phase and three-phase AC circuit theory
Single phase AC circuits: Phasors, real, apparent and reactive power, power factor.
Balanced three-phase systems: phase sequence, types of connection, powers, star-delta and delta-star transformations. Three-phase power factor correction. 

2 Fundamentals of Electromagnetism and transformers
Fundamentals of electromagnetism: force and torque in magnetic field, induced electromotive force. Inductance and magnetic circuits: self-inductance, mutual and leakage inductance; magnetic circuits and reluctance of the magnetic path, B-H curve of magnetic material, cores with air-gap. Induced electromotive force: induction in stationary systems with time varying fields and in systems with movable parts in time dependent and time independent fields. Losses in ferromagnetic materials.
Transformers: non-ideal single-phase transformer, equivalent circuit, tests to determine equivalent circuit parameters, losses and efficiency; three-phase transformers, winding connections.

3 Electromechanical energy conversion and steady-state analysis of DC machines
Electromechanical energy conversion: motoring and generating, time-domain modelling, torque and average torque, types of machines, rotating field. Steady-state analysis of dc machines: types, circuits and equations, speed-torque curve.

4 Steady-state analysis of AC machines
Steady-state analysis of induction machines: operating principle, equivalent circuit, phasor diagram, torque speed curve, losses and efficiency.

Electric Machines - 5511USST

Electric Machines

Analyse balanced three-phase circuits and power factor correction.

Appraise the principles of electromechanical energy conversion.

Apply standard tests on electrical machinery and analyse the results.

Assess and apply the laws of electromagnetism to engineering problems.

Discuss, analyse and evaluate steady-state operating characteristics of transformers, dc, induction and synchronous machines