OVERVIEW

The course aims to provide the technological foundations for the construction of low, medium and high voltage electrical equipment. The characteristics and properties of the insulating, conductive and magnetic materials which may be used are analysed. The variation of properties over time is analysed with particular reference to thermal and electrical ageing. The basic concepts for the calculation of dimensional characteristics of some apparechiature are given while the morphology of the single-phase and three-phase transformer and of equipment of different types is analysed in detail

AIMS AND CONTENT

LEARNING OUTCOMES

To know the technological solutions for the construction of electrical apparatuses both from the morphological point of view as well as from the functional one. To know how to set the preliminary design of static electric machines.

AIMS AND LEARNING OUTCOMES

To provide the elements on the morphology of electrical equipment for low, medium and high voltage. To provide the elements for the preliminary design of static electric machines.

PREREQUISITES

There are no specific requirements

TEACHING METHODS

48 hours of classroom instruction, 12 hours of classroom numerical exercises.

Students having disabilities or Specific Learning Disorders can request suitable aids for the examinations. Such aids will be defined according to specific needs, together with the Referent for the Polytechnic School of the Committe for the inclusion of Students with Disabilites and with SLD. Students in such conditions are invited to get in touch (via e-mail) with the Teacher a sufficient time before the examination, inserting in copy the Referent for the Polytechninc School (https://unige.it/en/commissioni/comitatoperlinclusionedeglistudenticondisabilita.html), without sending any document about their disabilites.

SYLLABUS/CONTENT

: References to the principles of operation of electrical machines. Dimensional relationships for electrical machines.       Main aspects of a project. Design constants of transformer machine.    

                General information on the cooling systems of electromechanical components. References to mathematical cooling models relevant to irradiation, conduction and convection. transients. Study of the continuous, limited and intermittent service. Service with variable loads.

Morphology, technological and design problems of transformers and coils. Outline of transformers. Typology, market situation, safety problems. Structure of dry and resin-based transformers. Structure of oil transformers. Types of insulating liquids. Cooling criteria with varying power. Accessories. Morphology of magnetic cores, stepped cores, oriented crystalline magnetic sheets. Morphology and problems related to BT, MT and AT windings. Isolation systems. Coils in foil, round wire and rectangular wire. Transposition of conductors. Methods of calculation of the magnetic circuit and of the windings. Calculation of dispersion reactance in the case of different types of winding. Short-circuit behaviour of radial and axial electrodynamic forces. Determination of the equivalent circuit, of the losses and of the no-load current. Additional losses. Overvoltage in components and plants and their classification. Circuits for impulse tests. Methods to withstand overvoltage in MT and AT transformers. Behaviour of transformer AT windings in the presence of overvoltage and use of screens.

Preliminary design of a transformer for MT: electromagnetic sizing and verification calculations.

Reactances in the air and with a core of ferromagnetic material, application criteria and dimensioning schemes.

Surge Protective Devices. Type of construction. Silicon carbide and zinc oxide SPDs. Dimensioning and use criteria and technological problems.

Classification of interruption equipment. Type of beakers BT, MT, AT depending on the arc interruption  and control type. Morphology and technological problems in the air, vacuum, in SF6. Limiter breakers. Breakers with interruption chambers in series with partitioning capacitors. Integrated systems for MT and AT in SF6 live and dead tank.

Switch-Disconnectors. 

Disconnectors.

Contactors.

Fuses. Types and characteristics of use. Constructive morphology.

Gas insulated systems in SF6. Cost and benefit assessment based on equipment costs and environmental impact problems. Morphology of GIS. Technological problems and insulating systems.

RECOMMENDED READING/BIBLIOGRAPHY

Notes of the Course

Costruzione delle Maccchine Elettriche, Giovanni Someda, editore Patron

Costruzioni Elettromeccaniche, Enrico di Pierro, editore Siderea

TEACHERS AND EXAM BOARD

Exam Board

FRANCESCO GUASTAVINO (President)

LAURA DELLA GIOVANNA

EUGENIA TORELLO (President Substitute)

LESSONS

LESSONS START

https://corsi.unige.it/corsi/8716/studenti-orario

Class schedule

The timetable for this course is available here: Portale EasyAcademy

EXAMS

EXAM DESCRIPTION

Oral exam: 3 questions, one open on the general topics on the program, one at the choice of the student, one on the project of a three-phase transformer of Medium Voltage. The students attending will be able to build the project during the lessons, by comparing themselves with the teacher.

ASSESSMENT METHODS

the exam will allow to verify the level of preparation considering also the quality of the exposure, the correct use of the specialized vocabulary, the capacity of critical reasoning on the study realized

Exam schedule

FURTHER INFORMATION

Ask the professor for other information not included in the teaching schedule