With the rise in demand for electric vehicles increasing, the need for high efficiency electrification systems is in high demand. One challenge is keeping full output power to the electric drives as the vehicle battery drops. This thesis presents a GaN based three-phase semi-quasi-z-source boost inverter that can produce twice the output voltage of a traditional inverter without the need for a boost converter stage. This single stage approach is great when the AC output voltage is relatively low. A second approach presented in this paper is a novel GaN based composite boost converter topology which is made up of a very efficient unregulated converter topology with an integrated partial power voltage regulation stage. This approach offers the benefits of very high efficiency from the unregulated converter stage and the regulated output voltage with the voltage regulation stage. This design can offer an estimated efficiency up to 98.6%.