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Cao Y.,Zhoukou Normal University | Zhang Z.J.,Zhoukou Normal University | Zhou C.,Xuchang Power Supply Company
Proceedings - 2012 International Conference on Computer Science and Service System, CSSS 2012 | Year: 2012

At present, the support vector machine (SVM) has been successfully applied in the field of electric load forecasting, but most of the load forecasting models are based on the day characteristics of meteorological factors, without considering a real-time weather factors which are valuable real-time information, while the prediction accuracy and generalization ability are influenced by the sample set of input variables. This paper aims to propose a selection strategy based on a sample of real-time weather factors. Firstly, data processing methods deal with abnormal points, secondly, then we use the day meteorological feature vectors to reduce the sample set, and use FP-Growth algorithm to select the training sample similar to prediction day based on real-time weather factors, finally prediction model based on SVM is established. The practical application shows that the text of the prediction models and processing strategies can be more accurate predictions. © 2012 IEEE. Source

Cui Q.-S.,XJ Electrical Co. | Wei Y.,XJ Electrical Co. | He Y.-J.,Xuchang Power Supply Company | Shi H.-G.,XJ Electrical Co.
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2011

This paper analyzes deeply the work principle, the clock model, delay computation mechanism, transport protocol stack, and the communication mode of precision clock synchronization protocol (Procision Time protocol), short for PTP1588. Based on the analysis of the protocol, combined with network characteristics and time synchronization requirements of the process network of the digital substation, key points of application in the process network of the digital substation are pointed out. Finally the application ideas of the protocol are summarized-PTP1588 is a general time synchronization protocol, so for a specific application, appropriate protocol mechanisms and parameters in PTP1588 should be selected based on this specific application's network characteristics and synchronization requirements to construct the application scheme. Source

Li S.,XJ Electrical Co. | Jia Z.,Xuchang Power Supply Company | Ying Z.,XJ Electrical Co.
Dianli Zidonghua Shebei/Electric Power Automation Equipment | Year: 2010

It is suggested to retrofit the non-integrated automation substation based on IEC61850 to meet the needs of smart grid construction. Only the station level and bay level of substation automation system adopt IEC61850 standard and the devices of monitoring, remote control, protective substation, measuring & control, bus-switchover and low-voltage protection are configured as new substation. The station level applies dual Ethernet based on IEC61850 protocol; the protection substation applies single Ethernet based on IEC61850 protocol; the low-voltage protection, measuring & control device, newly-configured high/medium -voltage protection sends data to monitoring devices via dual net based on IEC61850 protocol; the reserved protective equipments applying RS-485 or Ethernet 103 communication are upgraded by the manufacturers. According to the current status of non-integrated automation substations, it is pointed out that the retrofitting sequence, network equipment, increased AC/DC feeder cabinets and so on should be taken into account. Source

Li J.-G.,XJ Electrical Co. | Wang W.-Y.,Xuchang Power Supply Company | Ding H.,Power Supply Company of Changzhou | Di J.-F.,XJ Electrical Co.
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2010

This paper introduces functions of traditional fault recorder and analyzes its digital demand. At the same time, it researches the design of fault recorder device system based on IEC61850, discusses the technical program and modeling method to achieve its 61850 communication service. The fault recorder device has passed the national grid IEC61850 consistency test, gotten a satisfactory test results, and met the needs of power system. In the project , it has a good application prospects. Source

Li S.-H.,XJ Electrical Co. | Liu T.,XJ Electrical Co. | Su Y.,XJ Electrical Co. | Tong P.,Xuchang Power Supply Company | And 3 more authors.
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2010

Based on the design criteria for blocking/de-blocking of valve groups, this paper mainly studies the de-blocking/ blocking sequence and control strategies for groups under different circumstances. De-blocking the first group of a pole, simultaneously de-blocking both groups of a pole, and blocking the first group of a pole, simultaneously blocking both groups of a pole can be done the same way as that in a conventional bipolar HVDC scheme. The special coordinated sequence and control strategies for de-blocking the second group of a pole and blocking the last group of a pole are designed. In case of without telecom, de-block of second group of a pole is not recommended. In order to avoid unnecessary spill currents into the shutdown pole, the bypass switches of the blocked group is proposed to be left open. Source

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