Challenges and Implementation of Online In Situ RDSON Measurement in a Three-Phase Inverter

This article addresses the critical issue of real-time monitoring of
on
-state resistance (
R
_DSON
) of all power semiconductor devices within a three-phase inverter. An optimized
on
-state voltage (
V
_DSON
) measurement circuit and configuration for a multiphase converter architecture is proposed, designed to overcome the challenges posed by different characteristics and nonidealities of current and voltage sensor components. In addition to the hardware, the solution includes a data processing and qualification strategy that minimizes the impact of switching noise and processing circuitry nonidealities on
R
_DSON
calculation. The efficacy of the approach is demonstrated through experimental results from a three-phase inverter, which is designed with silicon carbide metal-oxide-semiconductor field-effect transistors. This work contributes a novel solution to the field, enhancing the reliability and efficiency of power semiconductor device monitoring.