Contents I. Introduction
The use of Gallium Nitride (GaN) power devices have been growing rapidly in recent years. The improved characteristics of GaN devices over Si resulted in expanding interests to utilize these devices in various applications [1]–[4]. GaN devices are being widely used where high switching speeds are needed to reduce the switching losses, improve the efficiency, and increase the power density. While switching at high speeds has many advantages for some applications such as dc-dc/ac-dc converters and power factor correction [5]–[6], the fast switching transients generate electromagnetic interference (EMI), which is partially caused by the common mode voltage (CMV) [7]–[9]. Specifically, the benefit of high switching transients of GaN for ac-ac and dc-ac inverters has not been thoroughly investigated. Faster transients in variable frequency drives (VFD) can create large EMI profiles and induce axial currents through bearings [9], reducing the lifespan of the motor. High dv/dt and di/dt also result in high voltage overshoots on the motor windings, causing damage to winding insulation and promoting partial discharge. Using large filters to suppress EMI increases the size, cost and efficiency of the inverter, reducing the benefits of using GaN devices.
