Modeling and Analysis of Zero Common-mode Voltage Modulation with Dead-Time for Three-Level Inverter

This paper presents the modeling and analysis of zero common-mode voltage (ZCMV) pulse width modulation with dead-time for three-level voltage source inverters. Analytical model to calculate phase output voltage harmonic of three-level inverter with ZCMV modulation is developed. With ZCMV modulation, the common-mode voltage (CMV) of a three-level inverter can be eliminated in theory. However, CMV reduction performance is limited by dead-time in practical applications. Hence, the harmonic characteristics of CMV is modeled and analyzed considering dead-time. Experiments are conducted on a three-level neutral point clamped inverter with ZCMV modulation, and verify the accuracy of developed models.