Power Internet-of-Thing B5G Networks for Differential Protection in New-Type Power Systems

Future power distribution networks, which contain extensive distributed generation (DG) and photovoltaic (PV), are normally modeled as T-connection with multi-terminal. Current differential protection (CDP) is an essential component for the fault removal, which requires the real-time and reliable power Internet-of-Thing (PIoT) communication to exchange the current information among the ubiquitous protection devices in future power distribution networks. Recently, the civilian 5G and beyond (5G/B5G) communication based on orthogonal frequency division multiplexing (OFDM) provide a potential communication solution to CDP; however, it cannot perfectly meet the reliability requirements for power services. Therefore, from the perspective of measured data transmission, a reliable PIoT B5G system based on subcarrier frequency-hopping OFDM access (FH/OFDMA) is proposed for the wide-area multi-terminal CDP in this paper. The integration of FH can help OFDM to resist interference and channel attenuation, and implement the multi-access in T-connection line terminals. The impact of data transmission error of PIoT FH/OFDMA on the action performance of CDP is analyzed in detail. Based on signal analysis, the mal-operation rate and refusal operation rate are simulated. The simulation reveals that, the proposed FH/OFDMA B5G has more stable transmission performance (a lower and balanced BER) for PIoT services, compared to the traditional OFDMA 5G scheme, and it can provide a low mal-operation rate and refusal operation rate for CDP service of T-connection line.