1、英文原文Research on Lightning Over-voltage Protection for500kV GIS SubstationAbstractThis paper combines incoming lines with 500kv GIS substation, considering the influence of the impulse voltage-second characteristics of insulator strings, the impulse corona of incoming lines, the impulse grounding res
2、istance of tower and the position of lightning. ATP-EMTP simulation program is applied to analyze the lightning over-voltage of 500kv GIS substation. The result shows that impulse corona and the resistance of tower which is close to the substation have great influence on over-voltage, when lightning
3、 strike the tower which is close to terminal door-typed structure, the lightning over-voltage may be not the most serious, and when the over-voltage of the equipment is very serious, a group of arrester is installed which can decrease the over-voltage effectively. This research thinking takes safety
4、 and economy into account, which can provide new reference for the engineering.Key words-GIS substation; impulse corona; grounding resistance;position of lightning; over-voltage.I. INTRODUCTION With the 500kV power transmission project construction and development, the electric power scientific rese
5、arch and design units are gradually in depth study and test, calculation and analysis of lightning incoming surge protection of 500kV substation as an important part has also made great progress. However, a number of scheme is not practical, some of them just over-emphasis on insulation margin not c
6、onsidered from the view of economic; some only through unilateral calculation gives scheme which left hidden troubles for safety. The 50% discharge voltage of insulator string as invaded wave was selected as in literature , such that method to select is not recommended because the impulse voltage-se
7、cond characteristics of insulator strings change with time. The impulse grounding resistance of tower and impulse corona was ignored as in reference , according to the actual situation in view, the model appears to be conservative and rough. The lightning strike spots was chosen 1# tower which close
8、 to door-typed structure (0# tower) as most serious to deal with, in some cases my be correct but not all cases. A large number of studies have shown that 1# tower top potential was reduced as 1# tower near 0# tower when lightning strike 1#. A large number of studies show that a large number of stud
9、ies have shown, when the lightning strike 1# tower which is next to the terminal gate-type framework, top potential of the 1# tower is reduced ,because the negative reflection wave return to the 1# tower by 0# tower , which make the overvoltage decreased. So only calculation lightning strike 1# is n
10、ot complete. This paper combines incoming lines with 500kv GIS substation, considering the influence of the impulse voltage-second characteristics of insulator strings, the impulse corona of incoming lines, the impulse grounding resistance of tower and the position of lightning. ATP-EMTP simulation
11、program is applied to analyze the lightning over-voltage effect about distant and near impact grounding resistance, the position of arrester which provide new reference for the engineering.II. MODEL FOUNDATION AND PARAMETER SELECTION ATPDraw is the most widely used on a electro-magnetic transient si
12、mulation, due to the graphic interface, makes this software convenient and accuracy by using. In this research,lightning models, transmission line models, tower model, arrester model, all of that be defined based on the characteristics of parameter, the transformer, disconnector, breaker etc, all of
13、 these can be expressed by equivalence impact entrance capacitance under the lighting wave.A. The equivalent circuit diagram of 500kV GIS Substation As shown in figure 1:this is a equivalent circuit diagram of 500kV GIS Substation, considering the security of system, “One Bus One Transformer” was ch
14、ose as the most serious running model of lighting over-voltage to simulation computation. As shown in figure: CVT is capacitor voltage transformer; DS is disconnector; CT is current transformer; CB is circuit breaker; F is arrester; T is transformer.B. Lightning Simulation Lightning current is belon
15、ging to unipolar pulse wave, Chinas standards recommended by lightning current amplitude probability distribution as follows: In this equality, I is lightning current, P is the probability of amplitude greater than I. This article taking the probability of 0.14% amplitude is 240kA wave of 2.6/50us a
16、s simulation lightning current.C. Insulator Strings Simulation As shown in Figure 2 is Insulator strings model, when the induced over-voltage is higher than voltage-second characteristics of insulator strings, the control switch will keep this export state which the part of criterion passed to 25 pieces of insulators of XP-160 style is used in this article the voltage-second characteristics of insulator strings which structure linear coeffic
