Advanced Materials Research Vols. 354-355

Abstract: Online monitoring is the precondition to achieve state maintenance and lifecycle management in power grid. Also, effective data transform model is the basis of online monitoring. We propose a data transform model for intelligent substation and PMS device online monitoring based on analyzing Standards of intelligent substation and State Grid. The PMS data are classified and compared with data model of IEC 61850 Standard. With methods of tag mapping and ID index we achieve the data conversion between intelligent substation and PMS.

Abstract: The regional discrepancies among various power systems are the preconditions for the integrated power system benefit. The national power grid has been formed initially. It provides the physical foundation for the benefit of integrated power system. Based on the analysis of resource distribution features of China and the generation structure features, the paper has reviewed the power grid development history and foreseen the development trends of the interconnected power system in China. The following integrated power system benefit has been analyzed: peak load regulation; hydro power and thermal power integration; cross-river basin adjustment; and scale merit, etc.

Abstract: Extension is a new subject which solves sontradictory problems. It studies the extensive possibility of things and the rules and methods of exploitation and innovation with formalized model. The extension control theory and method has provided the basis theory and method for people to solve the existent contradictory questions in the automatic control system such as stability, accuracy and speed.This paper briefly introduces the related basic concepts of extension control, such as the structure of canonical extension control, extension set of character status of basic extension controller, and general extension control algorithm, and so on. Also presents the extension applition in power systems. The future work and prospect of development are described.

Abstract: The calculations of short-circuit current decrement with PSS/E BKDY and computational curve were compared with the one by the dynamic simulation of PSS/E. Calculation shows that the accuracy of the result by PSS/E BKDY is quite good while the one by computational curve is so conservative that it makes larger errors. The reasons for the above results have been analyzed theoretically.

Abstract: The wind-light complementary based on pumped storage power system makes use of wind energy, solar energy and their complementary in time and area to generate clean power, and utilizes pumped storage to realize energy storage and backup power supply, which has broad development prospects. The paper begins with the necessity of making use of wind energy and solar energy, then introduces the structure characteristics, working principle, feasibility and advantages of the wind-light complementary based on pumped storage power system, and presents the system’s matching calculations.

Abstract: This paper first introduces the concepts( SCR, ESCR, QESCR ,H, and VSF.) and their usage. Later MIIF, equivalent admittance, MISCR and MIESCR, PBR are detailedly expounded. This paper put forward to the steps of the primary steady voltage stability work , detailed scheme of the steady voltage stability, the studing methods of the transient voltage stability in the multi-infeed AC/DC system. At last, the online voltage stability and the virtual smart power grid were put forward.

Abstract: Aiming at the solution of low communication rate, stability and anti-interference problem of Li-lion formation and test equipment, two controllers of TMS320F2812 DSP as lower controller and ARM as upper controller, are introduced as Controller Area Network (CAN) communicaton model in formation and test system to realize high speed and stable communication between bottom and top. This paper presents a scheme of using CAN technology to realize communication. The principle and communication protocol of formation and test system and hradware design are introduced in this paper.

Abstract: Since there are lots of qualitative indexes on safety assessment of the electric power supply company, the issue becomes exigent as how to transform qualitative descriptions to quantitative indication to make the safety assessment more scientific and accurate. Cloud theory which is based on traditional fuzzy set theory and probability theory consider the fuzziness and randomness, providing a powerful method for qualitative and quantitative information combining. This paper introduces Cloud gravity center evaluation in Cloud theory to safety assessment of the electric power supply company, which renders the reasonable transformation from qualitative concepts to quantitative descriptions. The case analysis shows the method is verified and scientific.

Abstract: The valve tray is the main device to support the voltage of HVDC. The faults of the cooling system of HVDC converter valve greatly impact the safe operation of the power grid. About 66% of the all faults are valve cold system stoppages which are caused by the electrode scaling, electrode gasket corrosion and the pipes clogged by scale which can lead to poor cooling. The scale was verified to be Aluminum compounds. This paper analyzes the cause of scale formation and offers some proposals to prevent scale formation.

Abstract: In this paper, the important methods is studied including frequency stability, short circuit ratio, primary frequency control ability, frequency regulation principle. The concept of “stability and control measure” is put forward and defined. The islanded operation and its influence on the northeast grid will be investigated which involves the maximal transfer power of the YiFeng AC lines and the verification of stability and control measures. The coordinating strategy between the spinning reserve and the frequency controller is proposed by studying the spinning reserve and its release, frequency controller, general frequency regulating ability. By studying the breaker, the disconnection boundary and the disconnection strategy, the operation mode can be determined. The critical flow through the breaker is put forward and defined. The islanded operation mode and stability and control strategy are studied. The fault cut time, the velocity of increasing/decreasing the DC power and the regulating step have an important influence on the islanded frequency stability. By studying integrating the islanded system into the HEILONGJIANG power grid, the connection strategy is decided. At last, the connection strategy of the local grid is determined and the overvoltage is studied in the Hulunbuir island .