Progettazione di Model Based del controllo orientato sul campo del motore brushless per la pompa del carburante per autoveicoli = Model based design of field oriented control of brushless motor for automotive fuel pump

In this master thesis control of automotive fuel pump has studied. Today, automotive fuel system is an important section of automotive that need improvement because of decreasing air pollution and also better way to decrease energy consumption. And fuel pump is one of important part of fuel system. With a sufficient fuel delivery, it is possible to remove the return fuel line to the fuel tank of automotive. For this purpose a good and sufficient fuel pump is needed. In the first chapter different fuel pump types are discussed. Then electric motor that is the main part of fuel pump described, after that best motor for fuel pump is selected. The main part of control that described in the thesis is the speed control brushless motor that with respect to it the fuel that pumped is controlled. Also, the other parts of motor control like torque is considered that they are described in detail in the following paragraphs. Fluid dynamic of the pump and which pump is a good option is also discussed and regenerative pump is selected and it used in simulation. Field oriented control (FOC) is one the best motor control that nowadays, it is also implemented to brushless motors. With FOC the motor the torque ripple is decrease, and current and speed control is also implement in FOC. One of control term that it is used is maximum torque per ampere (MTPA), with MTPA torque control is added to the control and also the quadrature current is created. Then Field oriented control is used for flux control of the motor. With field oriented control, it possible to increase speed when maximum back-emf is reached, it term of operation is like that it decrease the quadrature current that cause flux reduction and it will not allow the increase of the back-emf. In mechanical part of pump that it is casing and fuel pump, the regenerative pump is used. Regenerative pump is one the best pump for high pressure delivery of the fuel to the engine. It mathematical modelling and term of operation is described. And also the fuel characteristic that is one of important part of fuel pressure is also shown. For simulation of the fuel pump (motor and hydraulic) Matlab, Simulink and Simscpe are used. Then the result of simulation if shown in chapter 5. The simulation result shown the motor operation in reference speed change, battery state of charge change, field weakening. Also, the motor operation effect on fuel pressure and flow rate. And some safety operation that needed in modern electric fuel pump is also discussed, like stopping operation fuel pump during accident and fuel finishing in fuel tank.