A New Multi Carrier Based PWM for Multilevel Converter

This paper addresses a new multi-carrier modulation
technique called wave shift multi-carrier modulation (WSHM),
which used to control the cascade multilevel converter (CMC).
The proposed switching technique generates lower voltage total
harmonic distortion (THD) in comparison with conventional
multi-carrier based pulse width modulation (PWM) schemes,
phase-shift (PSHM) and level-shift (LSHM) modulations. To
compare the performance of proposed method with PSHM and
LSHM techniques, a simulation circuit of seven and nine levels for
CMC is designed and simulated. To complete the comparison
between the proposed method and PSHM, LSHM the dynamic
behavior of dynamic voltage restorer (DVR) based seven-level
CMC for power quality improvement is investigated. Digital
simulations are carried out using PSCAD/ EMTDC to validate the
performance of CMC.