Pulse Width Modulation methods for bidirectional/high-performance Z-source inverter

In this paper issue of pulse width modulation (PWM) methods for bidirectional/high-performance Z-source inverter (ZSI) is presented. Due to additional switch operating with the Z-network frequency an approach is different than in basic version of ZSI. Three various PWM methods are discussed: the state-of-the-art maximum constant boost control (MCBC), maximum constant boost control with discontinuous reference (DMCBC) and highly optimized minimum switching number (MSN). All methods are described in details and compared on the base of simulation test in SABER package and investigations of laboratory model of bidirectional ZSI. Impact of applied PWM method on inverter design process is also analysed - key issue is selection of passive elements (especially Z-network and line filter inductors).