Huang Yanhao

The construction of power system knowledge database based on ontology theory and semantic web technology

The development of Chinese Power System put forward the new requirements to the use of knowledge resources, but the knowledge database systems in Power Grid are unable to effectively manage and obtain the existing multi-type and distributed knowledge resources. For solving the problem, the model and architecture of new type knowledge database are studied and used to actual work. From the aspect of recording the relations between knowledge resources, based on ontology theory and semantic web technology, the knowledge management model with the core of objects is researched, including objects division, sub-ontology structure, basic relationships, and the formation of management directory. From the aspect of managing the distributed knowledge resources, the system architecture corresponding to the knowledge management model is studied, and the new functions in knowledge browsing, searching, and extracting are proposed too. Based on the above technologies the practical Power System new type knowledge database is built and tested in the network. The result shows that the new type knowledge database can preliminary meet the needs of Power System knowledge resources management and application, and has good scalability and development prospects.

Operation rule extracting based on time series association analysis in transient stability study

A robust operation rule extracting algorithm is proposed based on adaptive time series association analysis here. It is applied to extract association knowledge among the accumulating massive operation data. A data model describing the system state and topological structure before/after fault happening is built up at first. The initial abstract features are independent of the scale of a power system. A recursive principal component analysis method is employed to yield the reduced-size feature space. The extract features are then fed into the associative analysis. For considering temporal constraint, the generated associative rules not only reflect the relationship between power system operating condition and transient stability, but also reveal some valuable information about operating characteristics. Simulation results on on IEEE 39-bus test system demonstrate the feasibility and efficiency of the proposed method.