Secure Microgrid Clusters Under Integrated Satellite-Terrestrial Networks: A Differential Privacy-Preserving Control Strategy

Information disclosure is one of the key issues for microgrid clusters under integrated satellite-terrestrial networks (ISTNs), as it threatens data privacy and communication network security and can even compromise the safe operation of the entire power system. In this article, a differential privacy-preserving control strategy is proposed to enhance data transmission security among microgrid clusters under ISTNs. The proposed strategy also enables rapid frequency regulation and accurate active power sharing. First, the microgrid cluster model under ISTNs is developed. Given the wide coverage and complex link structures of ISTNs, microgrid clusters face significant information security risks during data exchange. To address this issue, nondecaying noise with invariant variance is introduced during information exchange to randomize the transmitted data and mask the original information from potential eavesdroppers. This approach significantly enhances data transmission security, thereby mitigating the risk of leakage in satellite communications caused by denial-of-service attacks, false data injection, or malware. Subsequently, a distributed differentially private consensus controller is developed. By introducing a time-varying control gain, the system achieves convergence with the expected accuracy and operates stably in the presence of nonattenuated noise, while meeting the predefined differential privacy index. Finally, the effectiveness of the proposed controller is validated through rigorous theoretical analysis and case studies conducted on the Object-Oriented Power Systems Advanced Laboratory for Real-Time Technologies (OPAL-RT) with digital signal processor controllers.