This dissertation focuses mainly on the airgap-less electric machine. An extensive literature review has been presented along with a systematic study that included analytical modeling, simulation with both steady-state and trasient analysis, prototype building, and experimental validation. In this type of device, the rotor is allowed to touch the stator at a contact point, which maximizes the internal flux and therefore the electromagnetic torque. A higher torque density motor is proposed in this dissertation due to a reduced reluctance caused by zero airgap situation. A comparison with other high torque density electric ma-chines demonstrates the advantages of the proposed machine. Switched reluctance motor for hybrid vehicle, integrated magnetic gear, induction machines, are some examples of the machines with lower torque density than the airgap-less electric machine. This machine will maximize the generated torque allowing these type of machines to be competitive in applications where hydraulic motors are prevalent, i.e., low-speed and high-torque requirements. Hydraulic motor systems face two major problems with their braking system and with low efficiency due to a large number of energy conversion stages (i.e., motor-pump, hydraulic connections and the hydraulic motor itself). The proposed electric motor, unlike hydraulic motors, converts electrical energy directly to mechanical energy with no extra braking system necessary and with higher efficiency. The evolution of the airgap-less electric machine from three poles to 9 bi-poles is discussed in this dissertation. The modeling of this machine with a minimum number of poles is discussed before a generalization is presented. The simulation and analysis of the airgap-less electric motor has been done using Euler integration method as well as Runge Kutta 4th order integration method due to its higher precision. A proof-of-concept electric machine with nine magnetic bipoles is built to validate the theoretical assumptions.

With the rapid growth of air travel, concerns about the emissions of greenhouse gas emissions resulting from the air transportation sector are growing. Although the current battery technologies might not be adequate for all-electric regional aircraft, the energy density of the current battery technologies could be adequate to electrify light-sport aircraft used for training and recreation. Due to the nature of the propeller load and noise isolation of the cabin, switched reluctance motors can be an excellent candidate for the propulsion system of electrified light-sport aircraft. The proposed SRM is designed to replace a 70 kW permanent magnet synchronous motor used in the aerospace industry with similar volume constraints and operational requirements. In order to meet the high-power density requirements of this application, a design framework is proposed which includes several layers of the design process. The design objectifies are the average torque, torque ripple, and radial forces by integrating the control and geometry design into the proposed framework. A comprehensive design process is carried out with the proposed framework, and a detailed coil design process is performed. The rotor cut-outs are designed to reduce the weight of the motor. The thermal performance of the motor has been analyzed for the calculated motor losses and the cooling system constraints. / Thesis / Master of Applied Science (MASc)