Theory and system design of online risk assessment on urban power system

This paper describes a practical method of Online Risk Assessment (ORA) on urban power system. It includes the Online Probabilistic Risk Indices (OPRI) & their arithmetic, and the models for computing parameters varying with operating conditions which are used for Probabilistic Risk Indices calculation. The ability of the method can provide operators in control center the near term identification on security level, weak point, and riskiest event of urban power system. Further more, the system architecture of Online Risk Assessment (ORA) is presented, which is the preparation of software implementation of Online Risk Assessment System (ORAS) on Urban Power System.