|Politecnico di Torino|
|Academic Year 2017/18|
Electrical Systems and safety
1st degree and Bachelor-level of the Bologna process in Electrical Engineering - Torino
The course aims at providing the basic notions concerning the structure and characteristics of the electrical installations for electricity production, delivery and utilization, with due attention to economic and environmental constraints. After considering the main components, the course will present the basic techniques for three phase systems, in normal state and after faults. The problems of protections against overcurrents and overvoltages will be presented next. Part of the course is dedicated to the general safety concepts and their application to electrical plants, including the main references to the most significant legislation and standards for electrical safety and to the prevention techniques.
The last part of the course is devoted to some basic concepts on electrical plants for final users and their preliminary design.
Expected learning outcomes
Ability to understand and interpret the structure and operation of electrical installations in High Voltage, Medium Voltage and Low Voltage systems, modelling the main components to study the operating conditions in normal state and after faults. Knowledge of the basic concepts on the interruption of the electric current and on the selection of the protection against overcurrents and overvoltages.
Ability to interpret and apply the concepts referred to safety and the related standards and regulatory documents.
Knowledge of the basic concepts of the design of user power plants, with ability to define basic scheme, to size the components in function of operating requirements and of the possible occurrence of anomalous events (short circuits and overvoltages), to identify the protections types and settings applying the relevant standards.
Prerequisites / Assumed knowledge
Basic knowledge of electrotechnics (circuit analysis and three-phase systems), basic knowledge of electric machines (transformer, synchronous and induction machines)
Generation, transmission and distribution systems
Structure of the electric energy systems:
generation, transmission, distribution
Power plant generation from conventional and non conventional sources.
Energy mix and operation in relation to the load diagram and to economic competitive environment
Electric lines (overhead lines and cables; thermal behaviour of cables, definition of ampacity, behaviour of cables in overload conditions and in faulty conditions)
Protection equipment (classification, interruption process of a direct current and of an alternating current, main devices). Protection relays. Circuit breaker.
Fault analysis of electric systems
Faults in electric systems
Design of Protection systems for cable lines
Overcurrent and short circuit protection. Standards. Basic system design of low voltage distribution systems.
Quality of supply
General definitions. Harmonic distortion. Voltage sags. Italian standards.
Power factor correction
Problems. Modalities. Technical rules. Design of a power factor correction system.
Classification. Schemes. Component sizing.
Safety and risk concepts. Legislation and standards. Effects of electricity on human body. Grounding. Protection against direct contacts. Protection against indirect contacts in TT, TN and IT systems. Extra-low voltage systems. Particular environments. Protection against lightning.
In addition to lectures, the course programme includes some laboratory activities:
- Thermal behaviour of cables and ampacity
- Interruption of a direct current and of an alternating current
- Power factor correction
- Faulty-circuit loop impedance measurement
- Ground resistance measurements
- Design of a low voltage distribution system.
Texts, readings, handouts and other learning resources
Lecture notes and material available on the course web site.
F. M. Gatta, Impianti elettrici, Esculapio, 2012.
R. Benato, L. Fellin, Impianti elettrici, Wolters Kluwer Italia, 2014.
V. Mangoni, G. Carpinelli, P. Varilone, Elementi di impianti elettrici di media e bassa tensione, Editore: Universitą di Cassino, 2010.
G. Conte, Manuale di impianti elettrici, Hoepli, 2014.
V. Carrescia, Fondamenti di sicurezza elettrica, TNE, 2008
Assessment and grading criteria
The exam consists of a written test and an oral colloquium. Both tests are mandatory.
The written test (2-hour long) will be held the date of exam (registration is necessary) and consists of 2 or 3 numerical exercises, multiple answer questions and open questions on the course contents.
The maximum score for each question/exercise is indicated in the text. The maximum score for the written test is 30/30.
An identity card is necessary. No text or notes can be read during the written text.
Results will be available on the course web site.
The oral colloquium includes some questions on the course contents, and could include the discussion on material produced during the laboratory experiences.
The final score refers to the knowledge and ability level reached on the different topics of the course programme.
Programma definitivo per l'A.A.2017/18