MV25404 Marine Electrical Machines – I – Semester IV – Marine – R-2025

Subject Code & Name: MV25404 – Marine Electrical Machines – I

Regulation: R-2025

Semester: IV (Fourth Semester)

Branch: B.E. Marine Engineering (Marine)

Credits / L-T-P: 3 Credits | L-T-P: 3-0-0

Course Objectives

• This course introduces the principles of electro-mechanical energy conversion and the construction, operation, and performance of marine electrical machines such as DC generators, motors, and transformers.
• It also covers motor characteristics and their application in efficient marine propulsion and shipboard electrical systems.

Full Unit-wise Syllabus

Unit I – Electromechanical Energy Conversion

Fundamentals of Magnetic circuits – Statically and dynamically induced EMF – Principle of electromechanical energy conversion forces and torque in magnetic field systems – co-energy in singly excited and multi excited magnetic field system – Winding Inductances – magnetic fields in rotating machines- magnetic saturation and leakage fluxes.

Activities: Students learn the fundamentals of magnetic circuits, EMF generation, and energy conversion through simple problem-solving, demonstrations, and short assignments on inductance and co-energy.

Unit II – DC Generators

Principle of operation, constructional details, armature windings and its types, EMF equation – armature reaction – demagnetizing and cross magnetizing ampere turns – compensating winding – commutation – inter poles – OCC and load characteristics of different types of DC Generators. Parallel operation of DC Generators, equalizing connections- applications of DC Generators.

Activities: Include diagram labeling, plotting characteristics, and solving numerical problems to understand construction, operation, and performance of DC generators.

Unit III – DC Motors

Principle of operation – significance of back e.m.f – torque equations and power developed by armature – speed control of DC motors – starting methods of DC motors – load characteristics –losses and efficiency – condition for maximum efficiency.

Unit IV – Testing of DC Machines

Brake test, Swinburne’s test, Hopkinson's test, Field test, Retardation test, Separation of core losses-applications of DC motors.

Activities: Students study motor operation, speed control, and performance through demonstrations, graph plotting, and basic testing methods with problem-solving exercises.

Unit V – Transformers

Construction and principle of operation – equivalent circuit – phasor diagrams – voltage regulation –losses and efficiency – all day efficiency – applications of single-phase transformer. Construction and working of auto transformer – comparison with two winding transformers – applications of autotransformer. Three Phase Transformer – Construction – types of connections and their comparative features–Scott connection, applications of Scott connection.

Activities: Learning involves drawing equivalent circuits and phasor diagrams, solving numerical problems, and comparing different types of transformers and their applications.

Unit VI – Fault Finding Techniques for Generator

Types of fault in main generator, Emergency generator, Fault finding techniques of main generator, Essential requirements for fault prevention and fault location in Generators Fault Rectification and actions to be taken on detection of fault in Main Generator and Emergency Generator.

Activities: Students analyze common generator faults, perform fault identification exercises, and develop flowcharts for troubleshooting and preventive maintenance.

Course Outcomes (COs)

• CO1: Explain the principles, construction, operation, characteristics, and fault-finding methods of marine electrical machines and transformers.
• CO2: Apply the concepts of electromechanical energy conversion, DC machines, transformers, and generator fault diagnosis in marine electrical systems.
• CO3: Analyze the performance characteristics, testing methods, efficiency, speed control, and operational behavior of electrical machines and transformers.
• CO4: Evaluate machine performance, transformer operation, generator faults, and maintenance practices for reliable marine electrical applications.

Assessment Pattern (Quick Note)

• Weightage: Continuous Assessment 40% | End Semester Examinations 60%
• Internal methodology: Quiz (5%), Assignments (25%), Review of GATE/ESE Questions (20%), Internal Examinations (50%)

Source: Official Anna University – B.E. Marine Engineering R-2025 Syllabus
Last Updated: October 2026