Practical Implementation of PWM Synchronization and Phase-Shift Method for Cascaded H-Bridge Multilevel Inverters Based on a Standard Serial Communication Protocol

The use of the controller area network communication protocol for H-bridge multilevel (HBML) inverters, and localized pulsewidth modulation generation and automated voltage regulation is proposed in this paper. It is shown that the performance and reliability of conventional distributed controllers for HBML inverters can be improved with less communication hardware requirements, when using the proposed method. It is also shown that the expansion and modularization capability of the HBML inverter is improved since individual inverter modules operate more independently. The proposed hardware is described in detail and the validity of the proposed system is verified experimentally on a 6600-V 1400-kW induction motor drive.