Open Conductor Faults Research Articles

Hierarchical Approach for Detection and Location of Open Conductor Fault in Power Distribution Networks

Hierarchical Approach for Detection and Location of Open Conductor Fault in Power Distribution Networks

Modified empirical arc model for simulating HVdc open conductor faults

Modified empirical arc model for simulating HVdc open conductor faults

Detection and Location of Open Conductor Faults for Power Distribution Networks Using a Contingency Analysis Approach

Detection and Location of Open Conductor Faults for Power Distribution Networks Using a Contingency Analysis Approach

Simultaneous series and shunt earth fault detection and classification using the Clarke transform for power transmission systems under different fault scenarios

For high-voltage (symmetric and non-symmetric) transmission networks, detecting simultaneous faults utilizing a single-end-based scheme is complex. In this regard, this paper suggests novel schemes for detecting simultaneous faults. The proposed schemes comprise two different stages: fault detection and identification and fault classification. The first proposed scheme needs communication links among both ends (sending and receiving) to detect and identify the fault. This communication link between both ends is used to send and receive three-phase current magnitudes for sending and receiving ends in the proposed fault detection (PFD) unit at both ends. The second proposed scheme starts with proposed fault classification (PFC) units at both ends. The proposed classification technique applies the Clarke transform on local current signals to classify the open conductor and simultaneous faults. The sign of all current Clarke components is the primary key for distinguishing between all types of simultaneous low-impedance and high-impedance faults. The fault detection time of the proposed schemes reaches 20 ms. The alternative transient program (ATP) package simulates a 500 kV–150-mile transmission line. The simulation studies are carried out to assess the suggested fault detection and identification and fault classification scheme performance under various OCFs and simultaneous earth faults in un-transposed and transposed TLs. The behavior of the proposed schemes is tested and validated by considering different fault scenarios with varying locations of fault, inception angles, fault resistance, and noise. A comparative study of the proposed schemes and other techniques is presented. Furthermore, the proposed schemes are extended to another transmission line, such as the 400 kV–144 km line. The obtained results demonstrated the effectiveness and reliability of the proposed scheme in correctly detecting simultaneous faults, low-impedance faults, and high-impedance faults.

Prevention of Wildfires Using an AI-Based Open Conductor Fault Detection Method on Overhead Line

Overhead lines that are exposed to the outdoors are susceptible to faults such as open conductors on weak points and disconnection caused by external factors such as typhoons. Arcs that occur during disconnection generate energy at a high heat of over 10,000 °C, requiring swift fault shut-off. However, most conventional fault detection methods to protect electrical power systems detect an overcurrent; thus, they can only detect faults after the line is disconnected and the cross-section of the line that generates the arc discharge makes contact with another line or the ground, causing a high risk of fire. Furthermore, in the case of ground faults owing to the disconnection of overhead lines, the load and the grounding impedance are not parallel. Therefore, in the case of the fault current not exceeding the threshold or a high impedance fault due to the high grounding impedance of the surrounding environment, such as grass or trees, it is difficult to determine overhead line faults with conventional fault detection methods. To solve these issues, this paper proposes an AI-based open conductor fault detection method on overhead lines that can clear the fault before the falling open conductor line comes into contact with the ground’s surface so as to prevent fire. The falling time according to the height and span of the overhead line was calculated using a falling conductor model for the overhead line, to which the pendulum motion was applied. The optimal input data cycle that enables fault detection before a line–ground fault occurs was derived. For artificial intelligence learning to prevent wildfires, the voltage and current signals were collected through a total of 432 fault simulations and were wavelet-transformed with a deep neural network to verify the method. The proposed total scheme was simulated and verified with MATLAB.

Detection and experimental investigation of open conductor and single-phase earth return faults in distribution systems

This paper presents a new and reliable detection approach for different crucial faults in distribution systems. These faults are one-open conductor faults at the far side of the feeder or simultaneous faults that are an open conductor followed by an earth fault at either the source side or load side (downed conductor-return faults). Under downed conductor-return faults, there is no zero-sequence current at the conventional protection point. Furthermore, the negative-sequence component is less than the normal unbalance component of the conventional protection point under one-open conductor faults at the far side of the feeder. Therefore, the presented detection approach is based on the measurements at the low voltage side of the load transformers. The proposed method detects such faults by monitoring only the magnitude of the measured three-phase voltage at the load side without installing voltage transformers. A robust threshold value is proposed to guarantee dependability against all fault conditions and security against the normal unbalance. Also, the security of the proposed approach against external faults (at the low voltage side) is verified by monitoring the magnitude of the three-phase current. Fortunately, the proposed system identifies the faulted section. The faulted feeder isolation and the faulted section isolation are accomplished by a proposed autonomous control method with the aid of the infrastructure of smart grids (available communication system). Extensive investigations are done based on a detailed simulation of the selected distribution feeder using the ATP-EMTP program. For verification purposes, recorded faulted cases are experimentally applied on a real distribution feeder to visualize such fault conditions and confirm the detection impossibility of earth-return faults by conventional protection, significantly if the fault faraway the substation. On the other hand, all applied test results corroborate the efficacy of the proposed detection method under the considered faults.

A New Wide Area Protection Scheme Based on the Phase Angles of the Sequence Components

— Several types of faults may occur in an active distribution network (ADN) such as single phase to ground, phase to phase, double phase to ground and three phases to ground faults. Many methods for the detection of all these faults are proposed in literature. However, the detection of open conductor faults is still a challenging task in distribution networks. These types of faults appear as a High Impedance Fault (HIF). This paper proposes a wide area protection scheme for radial ADN based on fault current component analysis. The proposed scheme uses the difference in the angles of the positive and negative sequence of the fault current between the main feeders and the branches of a radial ADN. The main feature of the proposed scheme is the ability to identify the faulted feeder even at HIF condition. Moreover, the proposed scheme can identify the faulty area along the faulty feeder. The effectiveness of the proposed technique is tested, using MATLAB/Simulink. Different scenarios are considered with various fault types including the open conductor faults. Simulation results demonstrate the effectiveness of the proposed scheme.

Detection of Open Conductor Fault Using Multiple Measurement Factors of Feeder RTUs in Power Distribution Networks With DGs

Open conductor faults are causing socioeconomic problems worldwide owing to fires caused by arc generation and increased risk of human electric shock. Also, the recent increase in the interconnection of distributed generators (DGs) has further aggravated the difficulty in detecting open conductor faults. In this study, we proposed a detection method for open conductor faults in power distribution networks using multivariate measurement factors of feeder remote terminal units (RTUs). The proposed method has the following advantages over the existing methods. First, the applicability in actual networks has been secured by utilizing the measurement values detectable in a general RTU. We analyzed the characteristics of open conductor faults according to the fault type, transformer connection, DG, etc., which we devised detection procedures for RTUs at the source-side and load-side of the open conductor point and developed an algorithm for open conductor detection. Using the proposed detection method, each RTU derived three results of open conductor alarm, warning, and no detection. Second, the detection problem caused by the DG in the existing open conductor method was rectified. Also, the limitations of classification between open conductor fault and other events were improved. Simulations using Matlab Simulink for a standardized power distribution network proved that the proposed method has a higher open conductor detection rate and distinguishing capability compared to the existing methods. Lastly, we demonstrated the applicability of the proposed method to a real system by deriving the optimal detection criteria using a sensitivity analysis.

Analysis of faulted power system during simultaneous open conductor and ground fault

To perform analysis of the simultaneous faults of transmission lines is one of the challenging tasks. Most of the algorithms fail to find the precise fault location under such conditions. An attempt is made in this study to analyse one of the simultaneous faults called open conductor and ground fault. The essential objective of this study is to derive generalised impedance equations to identify precise fault location during simultaneous open conductor and ground fault that occurred on a transmission line with the help of its equivalent sequence components network. The proposed method has less complexity for data processes unlike other methods such as advanced artificial intelligence, fuzzy logic, and neural networks. To validate the proposed method, simulations have been carried out using MATLAB/SIMULINK software on an existing different type of medium transmission line. Calculation results demonstrate the effectiveness of the derived equations claims around 95% accuracy to identify fault location. The proposed scheme also works very efficiently during more than one simultaneous open conductor and ground fault that occurred in the network. This study would be beneficial to the new researcher to analyse the behaviour of the network during the simultaneous fault having a basic knowledge of the formation of a sequential network for different types of faults.

Adaptive single-end transient-based scheme for detection and location of open conductor faults in HV transmission lines

Detection and location of open conductor in transmission systems using single-end data is a challenging task. This paper proposes a novel integrated scheme to detect and locate different types of open conductor faults (OCFs) in HV transmission systems. The proposed scheme unit (PSU) applies Discrete Wavelet Transform (DWT) with single-level decomposition on local current signals to detect OCFs correctly using adaptively estimated threshold values. PSU is also capable of dealing correctly with various normal transient conditions such as load/capacitor switching. To ensure quick repair of OCFs, PSU captures the transient voltage surges and applies a fault location scheme using DWT and Clark Transformation to accurately estimate the location of different OCFs types. Extensive ATP simulations are employed to check the PSU performance under various OCFs conditions on a 345kV, 100km transmission line. The achieved results confirm the effectiveness, robustness, and reliability of PSU in detecting correctly OCFs as well as the low-impedance faults within only 1.25 cycles. Moreover, the percentage error in estimating OCFs location is less than 1%. PSU has also confirmed its capability to be applied in cascaded lines without any communication or synchronization between PSUs.

Six phase transmission line protection against open conductor, phase to ground and simultaneous faults using fuzzy inference system

Conventional techniques fail to handle classification and location of simultaneous phase to ground and open conductor faults. In this regard, a novel classification and location strategy based on fuzzy logic is proposed in this paper. The main contribution of fuzzy strategy is to improve six phase transmission line (SPTL) under phase to ground and open conductor fault protection schemes. Moreover, fuzzy strategy identifies and locates simultaneous occurrence of open conductor and phase to ground faults. MATLAB software is used to simulate the SPTL. The measured instantaneous values of current in each phase at one end of SPTL are processed by low pass Butterworth filter, sampler and discrete Fourier transform. The obtained fundamental component of currents is selected as input to the proposed classification and location strategy. An advanced soft computing toolbox i.e., fuzzy toolbox, is used to implement fuzzy inference systems. From the simulation test results, the fuzzy strategies not only classify faults correctly, but also predict the location of faults precisely. The effectiveness and feasibility of fuzzy strategy is validated by the obtained test results considering the effect of variation in different fault parameters such as fault type, fault resistance, fault location and fault inception angle.

Six phase transmission line protection against open conductor, phase to ground and simultaneous faults using fuzzy inference system

Conventional techniques fail to handle classification and location of simultaneous phase to ground and open conductor faults. In this regard, a novel classification and location strategy based on fuzzy logic is proposed in this paper. The main contribution of fuzzy strategy is to improve six phase transmission line (SPTL) under phase to ground and open conductor fault protection schemes. Moreover, fuzzy strategy identifies and locates simultaneous occurrence of open conductor and phase to ground faults. MATLAB software is used to simulate the SPTL. The measured instantaneous values of current in each phase at one end of SPTL are processed by low pass Butterworth filter, sampler and discrete Fourier transform. The obtained fundamental component of currents is selected as input to the proposed classification and location strategy. An advanced soft computing toolbox i.e., fuzzy toolbox, is used to implement fuzzy inference systems. From the simulation test results, the fuzzy strategies not only classify faults correctly, but also predict the location of faults precisely. The effectiveness and feasibility of fuzzy strategy is validated by the obtained test results considering the effect of variation in different fault parameters such as fault type, fault resistance, fault location and fault inception angle.

Analysis of simultaneous unbalanced short circuit and open conductor faults in power systems with untransposed lines and six-phase sections

The paper introduces a generalized method for analysis of multiple, simultaneous short circuit, open circuit, and open circuit falling conductor faults in mixed three-phase and six-phase power systems with untransposed lines. The method is systematic and suitable for all types of faults, any number of simultaneous faults, and any number of phases. Calculation of all network unbalanced voltages and currents during faults is done in one straightforward step. Coupling among sequence networks in untransposed transmission lines is accounted for. Coupling between the three-sequence networks of the three-phase part and the six-sequence networks of six-phase part is also derived. The method is applied also for transient stability study of mixed three-phase and six-phase power systems during any type of faults. Detailed derivation of the governing equations in each part is presented. Simulation results on the IEEE 300-bus system and the IEEE 30-bus system are given to validate the proposed method.

Fuzzy Inference System Approach for Locating Series, Shunt, and Simultaneous Series-Shunt Faults in Double Circuit Transmission Lines.

Many schemes are reported for shunt fault location estimation, but fault location estimation of series or open conductor faults has not been dealt with so far. The existing numerical relays only detect the open conductor (series) fault and give the indication of the faulty phase(s), but they are unable to locate the series fault. The repair crew needs to patrol the complete line to find the location of series fault. In this paper fuzzy based fault detection/classification and location schemes in time domain are proposed for both series faults, shunt faults, and simultaneous series and shunt faults. The fault simulation studies and fault location algorithm have been developed using Matlab/Simulink. Synchronized phasors of voltage and current signals of both the ends of the line have been used as input to the proposed fuzzy based fault location scheme. Percentage of error in location of series fault is within 1% and shunt fault is 5% for all the tested fault cases. Validation of percentage of error in location estimation is done using Chi square test with both 1% and 5% level of significance.

Artificial Neural Network based Protection Scheme for One Conductor Open Faults in Six Phase Transmission Line

The demand for electricity is ever increasing. To meet this ever increasing demand, six phase line can be a possible alternative to increase the transmission line capacity of existing line with the same right of way. This paper presents a Artificial Neural Network based protection scheme for detection and classification of all one conductor open faults in six phase line. A 138 kV six phase transmission line of 68 km length has been simulated using MATLAB® software and its associated Simulink® and Simpowersystem® toolboxes. The fundamental components of current signals measured at relay location are used as input to train the Artificial Neural Network. The effect of variation in fault inception angle and fault distance location has been investigated on the performance of the proposed protection scheme. The simulation results of ANN based protection technique shows that proposed algorithm correctly detects/classifies all types of one open conductor faults within one cycle time. It validates the accuracy and suitability of the proposed scheme.

Analysis of the commutation failure of inverters during open-conductor faults at the AC side

Summary Commutation failures (CFs) in inverter stations disturb the power system greatly. Open-conductor fault (OCF) is a longitudinal fault. When it occurs in the alternating current (AC) system, the three-phase voltages are unbalanced. Under this circumstance, it is generally considered that inverters can maintain normal commutation order for the voltage support provided by other transmission lines in normal operation. In this paper, the possibility of the inverter CF during OCF is established. The sensitivities of the CF to the AC voltage disturbances caused by the changes of the AC superposition voltage are analyzed. It is concluded that the sensitivities of the CF with different transformer wiring schemes and fault types are diverse. Before the CF happens in the inverter station during OCF, the CF may occur in other inverter stations of the multi-terminal direct current systems with the constant current and constant extinction angle control strategies. Simulation studies are performed in the PSCAD/EMTDC software (Copyright(C)2006, Manitoba HVDC Research Centre, Canada), and the theoretical analysis is validated by the simulation results. Copyright © 2014 John Wiley & Sons, Ltd.

A New Digital Distance Relaying Scheme for Series-Compensated Double-Circuit Line During Open Conductor and Ground Fault

This paper presents a new digital distance relaying scheme which takes care of a simultaneous open conductor and ground fault occurring coincidently on the same phase at the same point on a series-compensated double-circuit line. The effect of series compensation, mutual zero-sequence coupling, remote infeed/outfeed, and fault resistance on the relay reach has been considered by the proposed scheme. The conventional digital distance relay having facility of series compensation fails to provide adequate protection in the presence of such conditions. The proposed scheme is based on the derivation of the compensated values of impedance using symmetrical component theory. To validate the proposed scheme, numerous computer simulations have been carried out using MATLAB/SIMULINK software on an existing 400-kV, 300-km-long series-compensated double-circuit transmission line. At the end, a comparative evaluation between the proposed scheme and the conventional scheme having a facility of series compensation is carried out. Simulation results demonstrate the effectiveness of the proposed scheme since the percentage error is within ±4.19%.

Faults locations in automated distribution system

This paper presents new techniques for locating short circuit and open conductor faults on automated distribution system. This is a unique method where short circuit and open conductor faults are treated simultaneously. The proposed fault location scheme is capable of accurately identifying the zone in which fault occurs. Temporary faults are also detected which may not result in a blown fuse. Data is made available to the substation remote terminal unit from various automated distribution system equipments. Decision is taken based upon the magnitude of fundamental frequency component of voltage and current phasor. Testing of proposed fault location method has been demonstrated on the laboratory model for its practical use. Analogues simulation results are obtained using electromagnetic transients program (EMTP).