Transmission Line Traveling Wave Fault Location Method Of Compensation Components Research

FACTS devices are used for the transmission line, which can increase the transmission power limit of the transmission line on the one hand, on the other hand, improve system stability. The transmission line impedance which contains a series compensator is no longer uniform. Parallel reactive power compensation device STATCOM is installed in the midpoint of the line. If the fault occurred in position before the STATCOM device, the STATCOM will inject current in to line, single-ended fault location based on Power frequency, the measured impedance according to the first terminal voltage and current calculation does not correctly reflect the fault location. With the rapid development of modern electronic technology, especially the development of microelectronics technology, the emergence of DSP and wavelet transform signal processing tools widely used in the extraction of fault transient information so that the fault traveling wave the reliability and accuracy of the ranging has been improved.The paper focuses on the transmission line traveling wave fault location of this major issue with FACTS devices. The working principle and mathematical model of the components STATCOM and TCSC components are analyzed and the operating characteristics of the control system is studied. The electromagnetic transient simulation model using simulation software PSCAD/EMTDC is built. The traveling wave is spreaded the TCSC components,if the frequency characteristics of series compensation has the influence of detection of the traveling wave head is worth studying. Series capacitor compensation has a strong refraction and reflection for the low-frequency component. With the increase in the degree of series compensation, the increase in the degree of series compensation, the refraction and reflection are stronger.For high-frequency component, with the of the higher the frequency, the stronger the effect of the refraction, the weaker of the reflection. It can be seen, contains a series compensation component fault location, the main reason is that the series capacitor compensation, but rather the operating characteristics of the MOV. The fault occurs in the line, the fault current flowing through the MOV is too much that the MOV is open. Capacitors are short circuit and the line wave impedance is mutated which result that another transient traveling wave is produce.The double-ended traveling wave fault location uses only the initial traveling wave. When the fault occurs in the line, the time of the MOV action caused by the fault is delay for a period of time after the fault. Double-ended fault location can eliminate the identification of the head of the traveling wave generated by the MOV action. For single-ended traveling wave fault location, if the fault is the single-phase ground fault, the second traveling wave head is may from the fault point, or from the bus, or from the un-fault line, or the traveling wave head caused by the fault point zero-mode transmission to the line of reflection of traveling wave mode, or may even caused by the MOV action. It can be seen that the traveling wave head increase in the in the timeline makes identification of the reflected wave head becomes difficult. The second traveling wave head is must be in identification the reflect wave from the fault point.The neural network has a massively parallel, distributed storage and handling, self-organizing, adaptive and self-learning ability, especially suited to deal with the need to consider many factors and conditions, imprecise and fuzzy information processing. Therefore, the neural network is used for fault location in order to identify the property of the second traveling wave head. So this can reach the precise positioning. Distance measurement of the impedance method, the input of STATCOM injected current to change the variable measuring impedance, thus the introduction of the ranging error. However, see the line wave angle of STATCOM on the impedance can be modeled as an inductor, the line wave high frequency can be regarded as open, and therefore does not affect the traveling wave in this catadioptric.The traveling wave method can be successfully applied to contain the parallel compensation line.