defgf67ay
Dołączył: 29 Paź 2010
Posty: 863
Przeczytał: 0 tematów
Ostrzeżeń: 0/5
Skąd: England
|
 Wysłany: Pon 18:59, 29 Lis 2010 Temat postu: ghd stijltang Capacitance of cable-body size distr |
 |
|
Capacitance of cable-body size distribution for the process of wave energy storage capacitor
To 508kV or above the rated voltage, high voltage capacitors that are expensive and bulky, not easy to use. Figure 1 Screen T Flash training theory until we know the wiring diagram, cable conductor and the enclosure large distributed capacitance between the cable conductor casing pressure can meet the above-ground 4 times the rated DC voltage, which makes us can make the best, with a sound body relative to the cable fault detection for distributed capacitance of the storage capacitor when】 l l mouth,[link widoczny dla zalogowanych], so that the problem can be solved Wave 2 cable fault detection process by the basic law of the basic principles of electromagnetic fields, current (voltage) wave velocity V along a certain wave impedance of the wire to the wave impedance five of five wire movement (Figure 2), when it reaches the junction point of two conductors (A), if ZI ≠ interaction, then the node (A) generated fold, reflection, a Received: 2OOl an energy of 03 points reflects a Post over the formation of refraction of the five current (voltage) wave. Forward movement along the five; another part of the energy reflected back to form reflected in the five current (voltage) wave (Figure 3), if neglecting losses,[link widoczny dla zalogowanych], this time off,[link widoczny dla zalogowanych], the following formula L33 reflection process can be said: 2Z, Tibet incident. ZlA reflection refraction around 2 ZAZ2 Figure 3d is the voltage reflection coefficient, 0% 2 = voltage reflection coefficient for the raccoon dog B, a 1B/1.2Z. . \current. i man shot current. in the cable fault detection fault land quality. often can be attributed to two kinds of typical open-and short-circuit state. disconnection fault for the open-circuit fault, then the equivalent of =*, low resistance fault,[link widoczny dla zalogowanych], high impedance leakage flashover faults and high resistance to short-circuit fault (or the impact of high DC voltage available to the flashover point of failure). At this time the equivalent of Jade = 0, then, reflection law 【Table 1 \conductor for the energy storage capacitor waveform analysis when measuring cable fault measurements shown in Figure 4 (direct flash method for example), measurement of the fault phase and end phase of a sound link with a short wire, this short course on the wave of cable can be neglected, the current coupler (current sampling used here) is on the fault phase and sound phases connected online to the cable jacket. The equivalent circuit shown in Figure 5, analysis of wave processes, the supply side due to a large impedance, can be regarded as open, c the impedance is very small, can be seen as short circuit, open-end sound phase. D to step-up transformer 4 1t Xi Jian Du phase electrical energy storage gradually prepare C test, the power boost, to a certain value insulation fault sudden flashover, flashover when the time is set to, t. Generates a current in the fault point mutation (negative current wave). After crossing the negative current time T / (for the wave propagation speed in the cable) arrived at the measuring end, the measuring end disconnect the power supply side can be considered, and C is equivalent to short-circuit, so the current wave of negative incident for the people through the C DO record, called the initial discharge pulse: while the B = 1, produces a negative current waves were the same along the fault phase and sound phases movement, movement along the fault phase after the negative current wave reaches the point of failure after T, then failure point of the flashover arc is not extinguished, so the fork have BF = 1 for total reflection, the reflected current wave through the T. Reach the end of the DO measurements are recorded. Called the reflected pulse fault movement along the negative current phase sound waves. After a time \That generate a positive current wave. This current wave and measuring the elapsed time T reaches the end of record for the DO. Reflection called the sound pulse phase at the end (after the wave process is omitted) to measure the release point barrier with a length of cable l K Figure 5 Equivalent circuit soap discharge pulse start shooting red beans around the point of failure in the test recorder 6 to the front of the recorded three current wave, because the energy storage capacitor C through differential role of differential spikes are shown in Figure 6, the cable length of the corresponding T, T corresponds to the test side from the point of failure. After recording the display will show the waveform corresponding to the distance between the test ended to the point of failure,[link widoczny dla zalogowanych], thus easy to detect the fault location. Such as the energy storage capacitor is not enough, you can also use the two sound together in parallel, when the transition process is slightly different, according to the basic principles of analysis. References: 『11 New Edition, Lv Lurong electric power to the installation, operation and so the peak Chun find fM] Beijing: Chemical Industry Press. 1994 [2】 Zhu Deheng. Yan Zhang 【which high voltage insulation. Beijing: Qing Mi University Press, 1990, 31 『Yu Zhuo stack design principle of electric power loving 【ridicule. Beijing: Mechanical Industry Press, 1999 Author: Xu Xingwen. Female, born in 1964. Guangdong, Tai Po. Undergraduate, lecturer. Power system research has been published on the straight two, [the three learning Ⅱ
More articles related to topics：
[link widoczny dla zalogowanych]
[link widoczny dla zalogowanych]
uggs ireland Deaerator water film heat transformat
Post został pochwalony 0 razy
|
|
