Mathematical Modeling of Device Currents in Space-Vector Modulated Two-Level Three-Phase Voltage Source Inverter

Accurate calculation of losses incurred in the power electronic converter is particularly essential in selection of devices and optimal thermal design. This article attempts to devise device current expressions in a space vector modulated (SVM) voltage source inverter (VSI). Emphasis is laid on deriving the equations which facilitate for quick and accurate calculation of conduction losses in the converter at different load conditions. Importance of the proposed work also lies in providing a generic way of mathematical modeling of device currents in complex pulse-width modulation (PWM) schemes. Initially, device currents in SVM inverter without considering dead-time was presented, where a generalized expression for offset voltage is derived. As dead-time is absolutely essential for safe operation of devices, effect of dead-time consideration on device currents is discussed. Finally, as channel of
mosfet
s can conduct bidirectionally, the device currents considering reverse conduction of
mosfet
s is presented. Simulation analysis is performed using
matlab/simulink
^{. The effectiveness of the derived expressions is also validated experimentally using 415 V, 5 kW SiC
mosfet
based voltage source inverter setup.}