Design and implementation of communication and control architecture for solar PV based microgrid supported by PEM Fuel Cell based auxiliary source

This paper presents the design and implementation of a hierarchical control structure supported by RS-485 based communication protocol for a laboratory prototyped AC Microgrid with Solar PV based converter as primary source and a PEM Fuel Cell (PEMFC) based converter as backup and auxiliary source. The control operation between Microgrid Master Controller (MMC) and Local Source Controller (LSC) is realized on LabVIEW platform. A communication network based on a MODBUS protocol is designed for monitoring the system parameters and status of all sources. A primary RS-485 based Master-Slave interface is also developed for the operational control of the Microgrid. The Solar PV based source is controlled by MMC to feed critical and non-critical loads under normal solar radiation conditions. The excess or deficit power is exported to or imported from the main grid. The PEMFC based source is used as an auxiliary source under grid-connected operation to support the system operation and as the backup supply under intentional islanded conditions to feed the critical loads. The Solar PV source is used to operate with current control mode and PEMFC source is operated in voltage control mode.