Electric vehicles appeared in the middle of the 19th century, with non-rechargeable batteries and a slight range. The first EV with mentionable range was the EV1, from General Motors in 1990. The development of EVs become less important in the 20th century due to the cheap gasoline, the fast spread of internal combustion engines and the fact that IC cars have much larger range. In addition, recharging IC cars with gasoline was much easier as a result of better infrastructure. Nowadays, considering the environmental impact of the IC based vehicles, along with the fear of oil field depletion, has led to revived the research and development towards EVs. Electricity can be produced from a wide range of sources, for example using fossil fuels, nuclear power and renewable sources such as wind power, solar power or geothermal power.
The purpose of this final project is to get familiar with the main principles of an EV discussing the structure, the operating modes and the dynamic model of it and to acquire the working conditions of its main part, the PMSM motor.
After a short introduction in the first chapter containing our personal motivations, the basics of an EV are detailed. The advantages and disadvantages compared to an IC vehicle, the categorization of different type on hybrid and purely electric vehicles, the structure, the operating modes for different hybrids, some safety regulations and a dynamic analysis for an electric vehicle can be found is the second chapter.
In the following chapter the theoretical background needed to understand how permanent magnet synchronous machines work is discussed, starting with the introduction of the trapezoidal (BLDC) and the sinusoidal (PMSM) winding synchronous motor. For applying linear control theory on a PMSM machine, Clark and Park transformation is necessary. At the end of this chapter the field oriented control used for the PMSM motor is presented.
In the fourth chapter the complete speed loop required to control a PMSM drive is designed, implementing the transformations, and the FOC discussed before. For the controllers, simple PI type was chosen, one for controlling the flux producing current component, one for the torque producing current component, and one for controlling the speed.
After this chapter some laboratory measurements were carried out with the help of some hardware provided by the department to test the control algorithm. In the last chapter a brief conclusion can be found with some future conception.