This paper presents a framework to classify threats to power system secure operation. Threats have long been recognized; however, there lacks a categorical classification of them due to various individual perspectives from different organizations. The power system is evolving to a smart, super, and clean grid, accompanied by interior diversified and emerging threats. Furthermore, threats from exterior factors, intentional and non-intentional, conventional and new-born, to power systems have become more severe than ever before. Therefore, a distinct catalogue, description, and possible impact of these threats are proposed to meet the need of preventing power system from dangers. Using the proposed classification, a quantitative trend analysis of more than a hundred representative historic blackouts is performed to figure out the principal threats and the changing trend of threats over time.
Highlights
► We conducted a survey and proposed perspectives on taxonomies regarding issues of power system security.
► Definitions and examples of various threats to power systems were given.
► A framework for classification of origins of threats to power system security was proposed.
► Based on the proposed framework, statistical analysis was performed to reveal the trend of threats.