The goal of the course is to provide the basic notions regarding the main types of electrical machines which are used for the generation of electrical energy and industrial applications: the synchronous and induction machines. For each type the operating principles and limits are analyzed with respect to the requirments of the electric power systems. 

Further, the course is focused on the electrical power systems issues by providing basic information on the structure of these systems and the criteria for a secure operation in a liberalized environment. In particular, it addresses issues related to the calculation of the power flows inthe transmission system and to the dispatching of generating units in presence of the liberalized electricity market. These issues will be treated taking into account the specific characteristics of both transmission and distribution systems. With reference to the distribution system, particular attention will be focused on the evolution of the networks toward smart grids.

Following the graduation of the course the student:

- will know the terminology and basic operation of the synchronous and induction machines;

- will understand the operation, the main characteriscs and the operating constraints of a real electrical power system;

- will understand the methods of operation and the associated constraints of the electric generators required for the operation of the electrical power system;

- will know the basic operating principles of the power electronic converters;

- will have basic knowledge on the aquirment of the regulating resources of an electric power system (ancilary services);

- will be able to make simple design choices regarding the sizing and definition of the operating point at the balance between electrical machines and electrical power systems;

- will be able to apply the aquired knowledge to simple problems sepcific to the electricity sector.

1. Introduction: definition of the main physical parameters for the study of electrical machines.

2. Introduction to electrical rotating machines: the electric rudimentary machine. Reversibility.

3. The rotating magnetic field: The Galileo Ferraris Theorem.

4. Synchronous machine: Principle of operation. No load and load condition. Mechanical characteristic. Fields of use.

5. Induction machines: Principle of operation. Induction motor: no-load and load condition. Torque calculation. Mechanical characteristic. Fields of use.

6. Outlines of Power Electronic Converters (Static Machines): Inverter. Rectifier.

7. Outlines of Wind generators: fixed and variable speed generators, Double-Fed Induction Generators (DFIG), Permanent Magnet Synchronous Generators (PMSG).

8. Introduction to power systems: outlines on the structure of the electrical system. The electric transmission and distribution systems. Admittance matrix: characteristics. Methods of calculation.

9. Power flow equations: Active and reactive power balance equations (Power Flow equations). Gauss and Newton's Method for solving the system of equations.

10. Security criteria: System states, N and N-1 security criteria. Total Transfer Capacity (TTC) definition. Zonal model of the transmission system.

11. Frequency regulation: primary, secondary and tertiary frequency control. Voltage regulation.

12. Ancillary Services: Ancillary Services Market.

13. Smart grid: Connection of generation facilities to the MV and LV distribution system.

Recommended bibliography

A selection of scientific papers and the following textbooks:

- A. E. Fitzgerald, Charles Kingsley Jr., Stephen D. Umans, Electric Machinery, McGraw-Hill Higher Education

- Giorgio Rizzoni and James A. Kearns, Principles and Applications of Electrical Engineering -  feb 2014, McGraw-Hill Education; 6 edition (1 February 2014), ISBN-10: 0073529591, ISBN-13: 978-0073529592

- John J. Grainger, William D. Stevenson, Power system analysis, McGraw-Hill, Jan 1, 1994.

- A. J. Wood and B. F. Wollenberg, "Power Generation, Operation and Control", Wiley, New York.

For a smooth following of the course the student is required to have basic knowledge of the mathematical formalisms and basic calculation tools, with specific reference to the treatment of complex numbers. Furthermore, basic knowledge of the physical principles of electromagnetism (Faraday-Lenz law, Ampere, etc.) and of electrical engineering (Ohm's laws, Kirchhoff, etc.) is required, as well as the ability to conduct the study of simple circuits in alternating sinusoidal periodic regime.

The evaluation of the student is performed by means of an examination that can be taken at the end of the semester or in any other available exam call.

There are no partial tests during the semester, only the final exam during the exam sessions.

The exam consists of a mandatory written test and an optional oral test that must be sustained within the same exam call.

The written and the oral test cover all the topics of the course: theory + finding the solution to simple numerical exercises.

The written exam consists of both numerical exercises and theoretical questions (2 exercises + 2 questions). The evaluation of the exercises is based on both their formal and numerical development.

The maximum obtainable score in the written test is equal to 27.

The oral test is necessary to obtain a score greater than 27 (at maximum 30 e lode).

Only if the score achieved in the written test is positive (i.e. greater or equal to 18), it is possible to take the oral test. Averagely, the oral test is held one week later with respect to the written test.

The evaluation of the student is considered positive if the overall score of the exam is greater or equal to 18/30.

There are no additional penalties for evaluating the written test as insufficient.

The evaluation of the oral test as insufficient, or resigning during the oral test even in the case of a positive evaluation, implies retaking the written test in the next exam call.

The exam has the goal to evaluate the theoretical knowledge of the treated topics and the ability of the student to:

- identify the parameters and construct the electrical model of the synchronous and induction rotating machines starting from the nameplate data of the machine;

- set-up and perform the analysis of the electric machines operating in steady-state conditions;

- set-up and perform power flow calculations on simple electric networks with the goal to identify and characterized the steady-state operation of the network (voltage profile, currents, power flows).