Small-Signal Model of a Voltage Source Inverter (VSI) Considering the Dead-Time Effect and Space Vector Modulation Types
Voltage source inverters (VSIs) are extensively used in power electronics systems, especially motor drive applications. In order to predict the correct performance of the inverter, there is always a demand for the development of accurate models. This work presents a modified small-signal model of a voltage source inverter (VSI) that captures model nonlinearities such as dead time and modulation effects that were not presented in the literature. Previous research has concentrated on developing compensation methods for these types of phenomena in a switching model, but none actually derived an analytical model that can predict them. In this work, the small-signal model of the VSI in literature is used, and the different phenomena are then incorporated into the model to get a complete one. In addition, the output impedance of the VSI is derived with the modified small-signal model, compared to the conventional one and validated with switching model and experimental results for stability analysis.