Modeling and analysis of shared/common DC bus operation of AC drives. I

The shared/common bus operation of AC motor drives is becoming popular in many industrial applications due to its advantages such as cost reduction, reduced space requirements and improved reliability. Depending on the application requirements, there are presently two methods to interconnect DC buses of AC drives: shared-bus; and common-bus. Very little or no work has been done in analyzing the use of such system configurations in industrial applications. This paper analyzes the different shared/common bus configurations in precharging, motoring and regenerating and addresses how to select the components, and connect the system together to ensure trouble-free operation, using PSpice simulations.