Development and testing of a three-phase SiC inverter-based eDrive

Permanent magnet synchronous motors are synchronous motors in which the field magnetomotive force is provided by permanent magnets. The use of rare earth magnet materials increases the flux density in the air gap and accordingly also in the motor power density and torque-to-inertia ratio: this makes these motors perfectly suited for applications like robotics and aerospace actuators, where it is preferable to have the weight as low as possible for a given output power. The thesis work deals with developing, testing and implementing the hardware and software needed for the motor to operate properly. The system consists of a DC-AC Inverter module with input filtering capacitors, the gate driver, voltage and current sensing boards and the PWM transmitting and receiving cards. The process involves the design of the bus capacitors; the testing of the gate driver; the double-pulse test of the inverter; the design, soldering and testing of current and voltage sensing printed circuit boards; the design, soldering and testing of the electric-to-optical PWM transmitting board and the optical-to-electric PWM receiving board. Before connecting the system to the motor, the behavior of the system is also simulated and tested without any load and with a resistive-inductive load. Subsequently, the system is connected to the permanent magnet motor and started firstly with V/f scalar control technique and then with I/f closed-loop technique, showing how the second is safer and offers the possibility to run the motor at higher speeds without the angular position feedback. Lastly, the closed-loop Field Oriented Control is designed and simulated for the system, ready to be implemented.