Modeling and control of master-slave microgrid with communication delay

Microgrids gathered a lot of attention in the last decade and are believed to be the future power systems. The renewable energy sources can be easily integrated into the Microgrid. Renewable energy sources such as PV, wind and fuel cells are usually connected through voltage-source inverters in the Microgrid. In order to share the same loads, these inverters are connected in parallel and to achieve the load sharing the control strategy is a must. In this paper, the master-slave control strategy in the dq frame is presented. The reference current signals are sent from the master to the slave converters. A model for master-slave communication-based Microgrid is presented and the system is modeled as a general time delay system. The maximum time delay that guarantees the stability of the system is calculated using a Lyapunov-Krasovskii based linear matrix inequalities method. The communication delay mimics the scenario when the wireless network or the Controller Area Network are used as a communication medium between the inverters.