Impact of Communication Latency on the Bus Voltage of Centrally Controlled DC Microgrids During Islanding

Maintaining a sustainable and reliable source of energy to supply critical loads within a renewable energy-based microgrid (MG) during blackouts is directly related to its bus voltage variations. For example, voltage variation might trigger protection devices and disconnect DERs within the MG. Centrally controlled MGs (CCMGs) type is dependent on communication. Therefore, it is very important to analyze the impact of communication networks performance degradation, such as latency, on the bus voltage of CCMGs. This paper investigates the effect of wireless communication technologies latency on the bus voltage and performance of DC CCMGs and how to mitigate it. Two mathematical models were developed to describe and predict the behavior of MGs during latency. As a case study, a renewable energy-based DC MG with its centralized control scheme was simulated to validate and compare the developed mathematical models. Results verify the accuracy of the developed models and show that the impact may be severe depending on the design, and the operational condition of the MG before latency occurs.