Improved Methodology for Estimating Switching Losses of Wide-Bandgap Semiconductors Using Gaussian Curve Fitting

The accurate assessment of switching losses is critical for evaluating the achievable performance of hard-switched applications implemented with wide-bandgap semiconductors. The traditional method for evaluating the switching losses for a particular semiconductor device requires integrating the calculated instantaneous power waveform to compute switching energy loss. However, a potential problem arises due to the need to select limits of integration within the power waveform. While there are published standards designed to reduce the arbitrary nature of limit selection, not all the device manufacturers subscribe to a single standard, and certain waveforms introduce ambiguity into the application of these standards. These factors compromise the ability to fairly assess and reliably compare performance between devices. To address this issue, this article proposes a switching loss estimation method based on Gaussian curve fitting that is not reliant on limit selection. The details of the proposed method are discussed herein, and results obtained from this method are compared to those from the published standards. As shown, this approach is simple and straightforward to implement, produces consistent results across a wide range of operating conditions and device types, and is especially suitable for automated postprocessing of switching waveforms.