Real-time PLC-based control for microgrid operations using SCADA system

Nowadays, significant advancements and semiconductor technologies in the field of microprocessor manufacturing provide high-volume memory, manufacturing, and production of programmable logic controllers (PLC). In these controllers, to change the logic of the control, it is sufficient to change only the control program without changing the wiring or devices. Easy installation and programming, short response time, high-speed control, simple testing and troubleshooting, network capability, as well as a noticeable reduction in wiring volume compared to traditional relay systems leading to PLC, have become one of the main pillars of the automation system. On the other hand, the use of microgrids as distributed power generation products to provide simultaneous electricity and heat, greenhouse gas emissions, and losses reduction in the supervisory control and data acquisition (SCADA) system, which is the most modern method of controlling and monitoring of automation systems. In this paper, we demonstrate how to test and program one of the Siemens PLCs called S7-1200 with the aid of TIA Portal V15 software to control the LAMBDA microgrid, placed at the University of Sapienza Rome that includes feeders related to photovoltaic panels, storage batteries and loads, in both grid-connected and island performance.