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Chen S.,Jiangsu Electric Power Company
Gaoya Dianqi/High Voltage Apparatus | Year: 2013

Based on the deepening understand on power quality conception, the paper analyses the relations between power supply reliability and power quality from the views of definition, indices and characteristics. It is concluded that the power quality issues are the extension of power supply reliability definition. The paper also points out that the indices of power quality evaluation should refer more to reliability indices family. Source

State Grid Corporation of China, Jiangsu Electric Power Company, China Realtime Database Co. and State Grid Suzhou Power Supply Company | Date: 2013-10-21

A method and an apparatus for splitting and recovering data in a power system are provided in the invention. The method includes the steps of setting a first database and a data recovery unit in a platform layer of the power system. The first database runs in a memory of the power system and is composed of the real-time image in the memory of a grid model and static parameters of a second database. The first database is used to provide the inquiry service of the grid model and static parameters for the power system. The data recovery unit is responsible for all of the associated read-write operations with the second database. After data are written into, the data recovery unit stores the data as historical data according to the time scale characters, and writes the historical data to the second database when the second database is normal.

Jiangsu Nanjing Power Supply Company, NARI TECHNOLOGY DEVELOPMENT Ltd COMPANY, State Grid Electrical Power Research Institute and Jiangsu Electric Power Company | Date: 2014-06-10

The invention discloses a global optimization and dispatching method based on time scales. The time scale based global optimization and dispatching method disclosed herein, relies on a target value system and a dispatch model. The global optimization and dispatching method depends on the results from a variety of subtopics. The methods provide adjustment and optimization in accordance with the time scales that are given in the sub goal of each sub topic: long-term, mid-long-term, short-term, ultra short term and real time optimization. Smart distribution grid can improve operational efficiency, integrated application of new elements in the distribution network of distribution energy network, micro grid, energy storage device and non-linear loads. This invention is fully adapted to the smart grid trends, with a good prospective.

State Grid Corporation of China, State Grid Suzhou Power Supply Company, NARI Technology Co. and Jiangsu Electric Power Company | Date: 2014-04-08

The invention provides an automatic mapping method for a distribution network based on logical layout, comprising (1) pretreating a model of the distribution network model by analyzing it, and partitioning and striping the distribution network model to generate a plurality of partial models; (2) analyzing an automatic mapping algorithm to be utilized by comparing a distribution network graph obtained by the algorithm with the distribution network model, to find out a basis for purposefully improving the partial models or the whole distribution network model; (3) achieving automatic layout of the partial models or the whole distribution network model on the basis of analysis of the automatic mapping algorithm to be utilized by combining with one or more of the force-directed layout algorithm, hybrid layout algorithm, dynamic interactive layout algorithm and an improved grid routing algorithm in order to generate the distribution network graph; and (4) analyzing and treating the automatic layout to achieve the generation of the distribution network graph with a desired practical effect. In the method of the invention, the automatic mapping of a distribution network is achieved on the basis of the distribution network by combining multiple mapping algorithms, thus the layout of the automatically generated distribution network graph is beautiful, clear and reasonable.

This invention publishes a fault diagnosis and location system for transformer core looseness, consists of vibration sensors, data collection and computer. It is of power transformer fault intelligent diagnosis technology technical field. Fault diagnosis and location method uses three vibration sensors positioned on the top of transformer tank, to obtain vibration signal, uses signal processing to analyze the signal, and obtains fault characteristics of the transformer core looseness. The characteristics respectively are 50 Hz, 150 Hz and 300 Hz frequency components, in which 300 Hz is main feature. When they reach a certain value at one position, it suggests that transformer core looseness near this position. By the comparison of differences among signals of three positions, fault location can be done. This invention manifests fault characteristics accurately and detects core looseness efficiently. The invention uses the electricity grid frequency of 50 Hz for example, for 60 Hz power system, above 50 Hz, 150 Hz, 300 Hz characteristic frequencies are 60 Hz, 180 Hz and 360 Hz.

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