Electric Traction and Vehicles

Electrical machines. Power Electronics

The teaching methodology consists of:
– Theoretical lectures, with projection of presentations and films (Powerpoint and others) on the topics covered, visits to relevant web pages; presentation of published case studies of research projects carried out at DEE-ISEC.
– Practical classes to carry out the work for evaluation, in group.
– Visit to DEE laboratories with R&D projects developed in electric vehicles.

Firstly, it is intended to help students become aware of the importance and problems of mobility and raise their awareness of possible solutions, which will inevitably go through electric traction (pure and hybrid), including new mobility strategies. Next, the principles and technologies used in electric road and railway traction are addressed, in order to provide students with technical knowledge and skills to face the emerging labor market in this area. Aspects of electric motorization in the aquatic environment (electric boats) are also addressed. Elements and directions are also provided so that the students can continue to study on their own and stay up to date after completing the course.

Goals / Skills

The state of development of our society is closely linked to the progress of transport and the increased mobility of people and goods. However, this increase has been made mainly at the expense of non-renewable energy sources (fossil fuels, mainly oil) and with serious environmental, energy, economic and external dependence consequences. In addition, the proliferation of private cars also causes problems of urban (im)mobility.

Thus, it is firstly intended to help students become aware of these problems and sensitize them to possible solutions, which will inevitably pass through electric (pu*re and hybrid) traction and new mobility strategies.

Then, the principles and technologies used in electric traction in road and rail are presented, in order to provide students with the technical knowledge and skills to face the emerging labor market in this area. Also included are aspects of electric propulsion in the aquatic environment (electric boats).

Many references and clues are also provided to enable them to continue the study on their own and to keep up to date upon completion of the course.

PART 1: THE PROBLEM OF TRANSPORT AND MOBILITY

1. IMPORTANCE OF TRANSPORT

  1.1. Relationship between transport and development

  1.2. Business volumes and people involved in the sector

2. THE PROBLEM

  2.1. Cost of oil, energy dependence, local and global environmental aspects; problem of urban mobility

  2.2. Negative impacts associated with rapid transport growth: accidents, noise, road congestion, air pollution

  2.3. Future prospects and forecasts for the number of vehicles in circulation, increased CO₂ emissions and energy needs

  2.4. Effects of gases emitted by transport and industries on the environment and human health.

  2.5. Kyoto Protocol and post-Kyoto Protocol.

3. POSSIBLE SOLUTIONS FOR THE ENERGY, ENVIRONMENTAL AND URBAN MOBILITY PROBLEM

  3.1. Development of cleaner, more efficient and sustainable vehicles. Comparison of technologies

  3.2. Encourage the use of public transport, improved energy and pollution, and diversification of fuels. Examples

  3.3. New concepts of urban mobility. Examples (“car-sharing”, electric bicycles and scooters, “Segway”, electric boats, other electric vehicles)

  3.4. Rethinking city planning (need for specific corridors, interconnection of public transport)

PART 2: ROAD ELECTRIC VEHICLES

1. ROAD ELECTRIC VEHICLES

  1.1. Types of electric vehicles (EV): with batteries (BEV) and hybrids (HEV); variants

  1.2. Components of an EV; Main components and choices to make for an EV

  1.3. History of EV

  1.4. Advantages of EV: comparison of efficiency, pollution and capital and operating costs. WTW, WTT, TTW analysis. Life Cycle Analysis

  1.5. Forecast and evolution trends of sales of EVs.

2. DYNAMIC MODEL OF ROAD VEHICLE

  2.1. Coordinate system, fixed land reference, vehicle reference

  2.2. Forces applied to the vehicle

  2.3. Total force of movement in the vehicle: Tire rolling resistance; Aerodynamic Strength; Road Tilt Force

 2.4. Parameters to be used to decrease power and energy for vehicle movement. Example of actions taken by various manufacturers

  2.5. Global Model. Equations of motion: dynamic wheel / electric motor; dynamics of the vehicle. Examples.

3. BATTERIES (Energy Storage Systems)

  3.1. Electrochemical accumulators

  3.2. Types of main batteries and features: Lead-Acid; Nickel-Cadmium; Sodium-Sulfur; Nickel-Iron; Zinc-Ar; Nickel Metal Hydrides; Lithium, …

  3.3. Battery chargers: normal charge; fast loading; Load equalization; Load infrastructures: Normal load and inductive load; energy requirements.

  3.4. Charging and discharging of batteries: ratting of batteries, depending on capacity and discharge time. Battery capacity as a function of discharge speed. Ideal loading and unloading cycles; Battery capacity over the life time; relationship between voltage, charge and electrolyte density; Charging current and constant voltage. Ideal charging and common charging. Caring for the initial and final charge. Problem and need of equalization

  3.5. Examples of manufacturer’s catalogs for Lead-Acid, Ni-Cd, Ni-MH and Lithium Ion batteries. Technical characteristics. Lithium ions: differences between isolated cell / cell and battery (cell grouped module)

  3.6. Mass of batteries required for a particular EV autonomy.

  3.7. Evolution of world production and prices of EV batteries

4. CELLS AND FUEL CELLS (Energy Storage Systems)

  4.1. Principle of operation: Constitution

  4.2. The “Fuel Cell” system: reformer, primary fuels, current inverter

  4.3. Parameters: electrolyte, electrodes, fuel

  4.4. Types of Fuel Cells

  4.5. Fuel: the problem of the production, transport and distribution of hydrogen. Other fuels

  4.6. Applications: motor vehicles

  4.7. Efficiency: comparison with BEV and ICEV (Internal Combustion Engine Vehicle)

5. SUPERCONDENSORS AND FLYING WEELS (Energy Storage Systems): Perspectives.

6. HYBRID EV

  6.1. What they are; structure and components. Existing models, features, series and parallel

  6.2. Operation. Strategies to increase efficiency. Operating differences between various models (Honda Civic IMA and Insight, Toyota Prius, etc.). Demonstration of operating modes

  6.3. Hybrid “Plug-in”

7. MOTORS AND DRIVES

  7.1. Components of the drive: power converters and their controller. Most used power semiconductors in electric traction

  7.2. Direct current: motors (series, separate excitation, permanent magnets) and its drives

  7.3. Alternating current: motors (induction, permanent magnet synchronous, brushless DC motors – BLDCM, switched reluctance motors) and drives. Methods of speed and torque control. Regenerative braking

8. STANDARDIZATION IN ROAD VEHICLES

PART 3: RAILWAY DRIVING

1. BRIEF HISTORY OF THE ELECTRICAL TRACTION: problems and technological evolution

2. EVOLUTION OF ELECTRIC TRACTION IN PORTUGAL

  2.1. The electric

  2.2. Metropolitano de Lisboa

  2.3. Portuguese Railways: generalities; CP rolling stock

  2.4. Metro Mondego Project

3. GENERALITY OF ELECTRIC TRACTION

  3.1. Voltages and frequencies; types of catenary

  3.2. Electrical scheme of an urban railway line

  3.3. Choice of current type (DC vs AC)

  3.4. Choice of contact line voltage value; voltage drop calculation

  3.5. Feed scheme of the “feeder”

  3.6. Calculation of the power of the transformers

  3.7. Calculation of copper conductor cross-section of the contact line

  3.8. Calculation of the inclination angle of the contact line with respect to the track axis

  3.9. Pantograph

  3.10. Catenary

4. ELASTIC MECHANICAL CONNECTION SCHEME for the bogie wheel drive

  4.1. Calculation of the transmission gear ratio

  4.2. Calculation of rail-wheel force

5. AXLE DISPOSITION AND DESIGNATION of the drive axles

6. EQUATION OF THE MOVEMENT. Resistance to advancement: force due to movement; force due to slope, force due to curves; force due to tunnels

7. TRANSMISSION OF THE MOVEMENT

8. DIMENSIONING THE POWER OF MOTOR VEHICLES

9. THERMOELECTRIC TRACTION

10. WEIGHT OF MECHANICAL AND ELECTRICAL PARTS

11. MECHANICAL BRAKING: generalities; brake shoes on wheels; disc brake

12. ELECTRIC BRAKING WITH RECOVERY

13. Direct current and alternating current drive systems: motors and drives for trains

14. HIGH SPEED TRAINS

Part 4: ELECTRIC BOATS

NAO

Main Bibliography
– Class presentations with links to relevant websites;
 – Selected articles from magazines and conferences.

All the English references presented above for the portuguese students