I. Introduction
Hybridpower systems with high penetration of renewable resources have become an important means to achieve carbon neutrality [1], [2]. In recent years, a series of network attack accidents occurred, which caused damage to the power system [3]–[6]. Wide-area distributed hybrid generation units with multi-time-scale dynamic characteristics integrated with open communication networks are vulnerable to network attacks [7], [8]. Thus, security problems of hybrid power systems must urgently be investigated from various perspectives [9]–[14]. In the study of secure control, vulnerability, resilience, and active defense are inevitable problems. Vulnerability analysis is studied with the aim of identifying the attack influence mechanism or cyber-physical permeation influences of hybrid power systems. Resilience analysis is studied to obtain the worst frequency performance under an explicit attack boundary. Active defense is studied to propose control and communication strategies to eliminate the attack influence on the stability. In this study, we focus on the vulnerability, resilience, and active defense of hybrid power system under DoS attacks.