Impacts of Cyber System on Microgrid Operational Reliability

A microgrid is a typical cyber-physical system. The coordinated control of each unit in a microgrid mainly relies on the cyber system. Once performance degradation of the cyber system happens, such as outages or transmission delay, the stable operation of the microgrid will likely be affected. In this paper, an analytical method is presented to quantify the impacts on the microgrid operation reliability from cyber system element failures and transmission interference. First, the link model and the information transmission model of the cyber system are established to describe the cyber routing path and the information transmission service quality, respectively. Then, the sequential Monte Carlo method is employed to simulate the operation of the microgrid. Finally, the impacts of the element failure and the transmission interference of the cyber system on microgrid operational reliability is quantitatively analyzed. Additionally, sensitivity analysis is carried out, focusing on the impacts of the cyber network topology, element failure rate and different types of information transmission quality indexes including delays, routing error, and information transmission error. The results of the numerical examples demonstrate the effectiveness of the proposed model and method.