
GIOVANNI FRANCESCHINI
Professore Ordinario Dipartimento di Ingegneria "Enzo Ferrari"

Insegnamento: Electric Drives/Electric Propulsion Systems
Advanced Automotive Engineering (D.M.270/04) (Offerta formativa 2023)
Obiettivi formativi
Electric Drives:
The course aims to provide basic knowledge on the principle of operation and modeling of the main electrical machines and the use of electric drives employed in electric propulsion and the control of the main electrical machines. DC and AC drives will be examined to highlight the operating characteristics.
Electric Propulsion Systems:
The course aims at providing knowledge and skills needed for the analysis and evaluation of the main hybrid and electric traction systems in the automotive field, including the main devices that compose them, such as electrical machines, power converters and devices for accumulation and recovery of electrical energy and their related control and management, in order to highlight the operating and use characteristics.
It also provides students with the essential tools to analyze and understand the quantitative aspects of the modeling and design processes in order to develop and carry out a noncomplex design project for a hybrid or electric drive system of a vehicle and analyze the results obtained.
Learning objectives, with reference to Dublin descriptors, are listed below.
Knowledge and understanding of the following topics concerning Electric Drives:
1. General theory of electromechanical conversion of energy.
2. Structure, operating principle, equivalent circuit of the following electric machines:
2.1 DC electric machine;
2.2 synchronous machine;
2.3 induction machine;
2.4 reluctance and IPM synchronous machines
3. The four quadrants of operation concept, regenerative braking. Constant torque and constant power operating area. Maximum Torque per Ampere (MTPA) operation. Voltage saturation operation: maximum torque per volt, MTPV. Overload operation, effective torque concept.
Knowledge and understanding of the following topics concerning Electric Propulsion Systems:
4. Electric drives control chain components. Implementation of closed control loops. Transducers of electrical and mechanical quantities.
5. Vector control of AC machines
Prerequisiti
Basics of Electrical engineering and automatic controls.
Programma del corso
Topics related to Electric Drives
Electromechanical energy conversion: Energy and Coenergy. Determination of force / torque delivered by an electric actuator. (ECTS 1, 10h )
Operating principle of the DC machine, permanent magnet and wound stator construction. Equivalent circuit and dynamic model. Mechanical characteristic, constant torque and constant power operating area. Overload operation, introduction of the effective torque concept. (ECTS 2, 20h )
Structure of synchronous machines and brushless motors with permanent magnets. Principle of operation of the trapezoidal and sinusoidal brushless motor. Stationary and dynamic model of permanent magnet machines. Fields of application and comparison with the DC drives. (ECTS 0.5h )
Structure and operating principle of the induction machine. Dynamic model of induction motors. Field Oriented Control.
Structure and operating principle of synchronous reluctance and Interior Permanet Magnet Machine: dynamic models and vector control.
Optimal control of IPM motors: MTPV and MTPA trajectories. (ECTS 2.5h ).
Topics related to Electric Propulsion Systems
Introduction to the main powertrain architectures and components (ECTS 0,5, 5 hours)
One dimensional analysis of the vehicle dynamics, determination of the characteristic curve
Powertrain energy flow and efficiency analysis (ECTS 1, 10 hours)
Electric motor working principle, main machine characteristic parameters
(ECTS 1, 10 hours)
Components of the control system of electric drives. Structure of the main control architectures, vector control of AC machines, spatial vector modulation.
(ECTS 1, 10 hours)
Optimal control of electrical machines: MTPA, FW and MTPV trajectories.
(ECTS 1, 10 hours)
Introduction to the electric machine design, torque equation, magnetic loading, current loading, types of winding and cooling systems.
(ECTS 1,5 15 hours)
Metodi didattici
The course is delivered in English and includes facetoface lectures (theory and calculations) with connection also in streaming for students who follow from home via the "Teams" platform.
The lessons are carried out with the aid of multimedia systems and can also involve practical exercises in which students are divided in small groups (23 for each PC) and utilize software for the simulation of hybrid and electric traction systems (Matlab / Simulink and PLECS), solve problems and discuss the results among themselves and with the teacher.
In addition, professors receive students by appointment for clarification and personalized tutoring.
The teaching material will be made available at the end of each lesson through the “Teams” platform.
Mathematical models will be used for numerical modeling and computer simulation with Matlab / Simulink and PLECS.
Testi di riferimento
On the TEAMS of the course (in compliance with copyright)
 The notes used by the professor during the lectures and numerical exercises
 the slides of the lessons
 The mathematical models introduced for numerical modeling and computer simulation with Matlab / Simulink and PLECS
A. E. Fitzgerald , C. Jr. Kingsley , A. Kusko: "Electric machinery", McGrawHill Education, 2012.
A. Emadi, “Advanced Electric Drive Vehicles (Energy, Power
Electronics, and Machines)”, CRC Press; 1st edition (2014).
N. Mohan, T. M. Undeland, W. P. Robbins: “Power Electronics: Converters, Applications and Design”, John Wiley & Sons Inc;
Mehrdad Ehsani, Yimin Gao, Sebastien E .Gay, and Ali Emadi: "Modern Electric, Hybrid Electric, and Fuel Cell Vehicles Fundamentals, Theory, and Design, CRC Press, 2009.
Verifica dell'apprendimento
The exam will take place at the end of the course according to the official exam session calendar.
The examination is composed of a practical project and an oral discussion:
1: Application project with the drafting of a report on one of the following topics:
a) the simulation and design of an electric / hybrid vehicle.
b) the design of an electrical circuit for motor control.
The deliverable report on the activity carried out, including simulation and/or experimental results will be graded.
The evaluation of the project is expressed out of thirty (a score greater than 30 results in obtaining a grade: 30 with honors).
2: an oral exam aimed at verifying the knowledge of the course contents. The oral exam consists in the discussion of the project activity carried out and 1 or 2 questions regarding the topics of the course. The oral exam will last approximately 40 minutes.
The evaluation indicators are:
 Ability to use knowledge (25%)
 Ability to connect knowledge (25%);
 Mastery of technical language (15%);
 Ability to discuss topics (20%)
 Ability to deepen the topics (15%)
The evaluation of the oral exam is expressed out of thirty (a score greater than 30 leads to obtaining the grade: 30 cum laude).
To pass the exam both tests (application project and oral exam) must be sufficient (exceed the threshold value of 18/30). The final grade is the average of the marks obtained in the two tests, a score greater than 30 leads to obtaining the grade: 30 with honors.
The grade will be determined and communicated at the end of the oral exam.
Risultati attesi
At the end of the course, the students will be able to:
know of the General Theory of Electromechanical Energy Conversion;
structure, operating principle, equivalent circuit of the principal electric machines;
 knowledge of Electric Drive Control Chains and their Main Components, application of advanced vector control techniques to AC electrical machines;
Ability to critically apply the acquired knowledge to the problems of sizing, modeling and simulation of an electrical drivetrain.
 describe clearly the main components of a hybrid or electric drive system and their main characteristics.
for each type of hybrid or electric system, The students will be able to recognize:
 the construction details of the electric motors;
 the principles of operation;
 the main control schemes and algorithms of electric motors;
 Analyse and evaluate the quantitative aspects of the modelling and design processes of a hybrid or electric drive system of a vehicle
 Express a critical judgment on the main devices that constitute a hybrid or electric traction system including: electric machines, power converters
Communication skills
 Clearly communicate the knowledge and understanding skills acquired.
 Use correctly and appropriately the language, concepts and models acquired to effectively discuss the design solutions and the main solutions for the sizing of hybrid or electric traction systems
Ability to learn
 Apply the knowledge and understanding skills learned to other topics related to the design of electric vehicles
 Independently update the knowledge and understanding related to the design and analysis of electric vehicles.