Research On Parallel Connection Of Energy Storage Inverters Based On CAN Bus With Democratic Master-Slave Control

In distributed energy storage systems, inverters are indispensable. Parallel connection is one of the effective ways to expand the capacity of the inverter. However, there are many problems such as current unevenness in the inverter cascade system, especially when the inverter module is in different working conditions, such as module switching, inverter load/reduction or even the module exits operation due to failure, the system will become unstable. When the transformer is added or removed, even if the module fails and exits, the system will become unstable. In this paper, the experimental platform of two inverters running in parallel is taken as the research object. The democratic master-slave control mode based on CAN bus strategy is proposed, and the superiority of the democratic master-slave control mode is clarified from the perspective of system stability. In the experiment, the output voltage quality is increased by using fewer interconnection lines, ensuring high reliability operation of the system.