Fault location method for partial coupling four-circuit overhead lines with different voltages

With the rapid development of distribution networks, two-terminal overhead lines have been used on a large scale for higher power supply reliability, thus the fault location has attracted much attention. Accurate fault location is helpful to shorten the outage time and improve the economy of operation greatly. However, since insufficient standardization of equipment selection and poor management, line parameters are usually inaccurate or even unknown, mature fault location methods based on impedance can’t be applied anymore. Also, the asymmetry caused by non-transposition in distribution networks affects the accuracy of fault location. This paper proposes a fault location method for two-terminal untransposed overhead lines without requiring line parameters. Firstly, this paper considers parameter asymmetry, and the mutual impedances between the three phases are set as different values. Secondly, the location equations rely on three-phase networks, then the self-impedance and mutual impedances are regarded as unknowns and solved directly. Finally, this method takes the average value of fundamental frequency components from different data windows, which reduces error and improves accuracy. The simulation results show that the fault location method has high accuracy, and can effectively overcome the influence of unknown line parameters and non-transposition.

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A Reactance-Based Fault Location Method for Overhead Lines of AC Electrified Railway

IEEE Transactions on Power Delivery ◽

10.1109/tpwrd.2020.2974162 ◽

2020 ◽

Vol 35 (5) ◽

pp. 2558-2560 ◽

Cited By ~ 1

Author(s):

Zhengqing Han ◽

Shuai Li ◽

Shuping Liu ◽

Shibin Gao

Keyword(s):

Fault Location ◽

Location Method ◽

Overhead Lines ◽

Electrified Railway

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A Novel Fault-location Method for HVDC Transmission Lines Based on Concentric Relaxation Principle and Wavelet Packet

Recent Advances in Electrical & Electronic Engineering (Formerly Recent Patents on Electrical & Electronic Engineering) ◽

10.2174/2213111607666191003105654 ◽

2020 ◽

Vol 13 (5) ◽

pp. 705-716

Author(s):

Congshan Li ◽

Ping He ◽

Feng Wang ◽

Cunxiang Yang ◽

Yukun Tao ◽

...

Keyword(s):

Transmission Lines ◽

Traveling Wave ◽

Fault Location ◽

Wave Attenuation ◽

Wavelet Packet ◽

Low Frequency ◽

Evaluation Process ◽

Location Method ◽

Hvdc Transmission ◽

Instantaneous Energy

Background: A novel fault location method of HVDC transmission line based on a concentric relaxation principle is proposed in this paper. Methods: Due to the different position of fault, the instantaneous energy measured from rectifier and inverter are different, and the ratio k between them is the relationship to the fault location d. Through the analysis of amplitude-frequency characteristics, we found that the wave attenuation characteristic of low frequency in the traveling wave is stable, and the amplitude of energy is larger, so we get the instantaneous energy ratio by using the low-frequency data. By using the method of wavelet packet decomposition, the voltage traveling wave signal was decomposed. Results: Finally, calculate the value k. By using the data fitting, the relative function of k and d can be got, that is the fault location function. Conclusion: After an exhaustive evaluation process considering different fault locations, fault resistances, and noise on the unipolar DC transmission system, four-machine two-area AC/DC parallel system, and an actual complex grid, the method presented here showed a very accurate and robust behavior.

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