PUBLICATIONS

This paper proposes a thermal reduction method of

DC-link capacitors and SiC MOSFETs in two-level inverters

based on discontinuous PWM. The converter reliability has been

extensively studied at both the device and the inverter levels

through physics of failure analysis. The failures of switch modules

and capacitors constitute about 50% of inverter system failures,

primarily due to cumulative thermo-mechanical damage from

power loss and thermal stress. The power loss and thermal

behavior of switching modules are analyzed to reduce the rate of

failures in this paper. The proposed method alleviates the thermal

stress by applying discontinuous PWM, thereby decreasing power

loss. Moreover, a phase-shifted scheme is applied to decrease the

ripple current by reducing the loss and temperature of the DClink

capacitor, despite a deterioration in the total harmonic

distortion (THD) of the output current. The proposed thermal

reduction method is verified by simulation results.