Research on Source Maintenance Key Technology of the Smart Substation

The source maintenance technology of the smart substation offers the base for the models, data and graphs sharing between the substation and the dispatch center. This paper researches on the conversion technology between SCD model in IEC 61850 Ed. 2 and the CIM model in IEC 61970. The substation provides SVG and SCD documents to the dispatch center, which includes primary equipment information and the network topology. The dispatch center’s automation system completes the conversion between the two models. This paper researches on the smart remote technology, which uses IEC 61850 as communication protocol. It can filter and restructure communication data based on the needs of different dispatch center. At the same time, it can provide quality control of communication link, to ensure that the important data be sent in real time.

Bi-Level Energy Management Model of Grid-Connected Microgrid Community

As the proportion of renewable energy power generation continues to increase,the number of grid-connected microgrids is gradually increasing,and geographically adjacent microgrids can be interconnected to form a Micro-Grid Community(MGC).In order to reduce the operation and maintenance costs of a single micro grid and reduce the adverse effects caused by unnecessary energy interaction between the micro grid and the main grid while improving the overall economic benefits of the micro grid community,this paper proposes a bi-level energy management model with the optimization goal of maximizing the social welfare of the micro grid community and minimizing the total electricity cost of a single micro grid.The lower-level model optimizes the output of each equipment unit in the system and the exchange power between the system and the external grid with the goal of minimizing the operating cost of each microgrid.The upper-level model optimizes the goal ofmaximizing the socialwelfare of themicrogrid.Taking amicrogrid community with four microgrids as an example,the simulation analysis shows that the proposed optimization model is beneficial to reduce the operating cost of a single microgrid,improve the overall revenue of the microgrid community,and reduce the power interaction pressure on the main grid.

A Transformer Replacement Decision Method Based on Probability Assessment of Failure Rate

Reasonable probability assessment of transformer failure rate (FR) is a critical reference to the transformer replacement work. At present, the lack of support theory for transformer replacement usually causes reliability and economy issues for power companies. For this reason, a transformer replacement decision method based on probability assessment of FR is proposed. Firstly, a first order model of transformer paper degradation is proposed. Then, the Weibull Distribution is used by Monte Carlo Simulation (MCS) to generate the variations of Degree of Polymerization (DP) along with time based on the historical data, and the transformer FR is determined. When the FR is higher than a pre-defined threshold value, the transformer should be replaced for reliability purpose. Finally, the effectiveness of the proposed method for the transformer replacement decision is verified by a typical engineering application.

Battery Energy Storage System Information Modeling Based on IEC 61850

This paper discourses the typical ways to access system of the battery energy storage system. To realize the battery energy storage system based on IEC 61850, hierarchical information architecture for battery energy storage system is presented, the general design and implementation methods for device information model are elaborated, and the communication methods of the architecture are proposed. Example of battery energy storage system information model based on IEC 61850 tests that the battery energy storage system information architecture established is feasible.