Electric Discharges Localization for Substation Fault Monitoring Using Two Elements Sensor

2020 ◽  
Vol 17 (2) ◽  
pp. 1009-1013
Author(s):  
Lorothy Morrison Buah Singkang ◽  
Kismet Anak Hong Ping ◽  
P. R. P. Hoole

A substation is an important unit in the electric power system. Thus, the monitoring process must be carried out effectively to detect the operation status of the equipment, and pre-fault threat detection is necessary for safe operation. Many methods and intelligent techniques have been developed to provide a better way of fault detection. However, power authorities unwilling to adopt those techniques due to the high cost of installation and more sensors required to improve localization accuracy. Therefore, to reduce cost and increase the speed of detection, this paper presents a 2-element array antenna acted like a sensor to detect and localize the electric discharges from abnormal radiated electromagnetic activities in the substation based on the direction of arriving angle (DOA) received by the array antenna. Software implemented signal processor was used to obtain the radiation patterns for different value of DOA relative to the normalized Array Factor (AFN). This 2-element Sensor was proven to eliminate the undesired signals (such as electromagnetic signals from outside the substation) and maximize the signals in the direction of the desired signal by detecting the DOA of abnormal radiation from power apparatus (such as power transformer or circuit breaker bushings) inside the substation. It was proven that this cohesive unit was able to perform the two tasks by simultaneously eliminating or maximizing signals with very small (such as 0.0873 radians) angle difference between external radiation and radiation from apparatus inside the substation. By performing these tasks, the 2-element Sensor was promisingly able to detect and localize the abnormal electrical activities such as Electric Corona and Electric Arcs discharges that may occur in any substation based on the identified DOA from the power apparatus within the substation as a preventative approach for substation breakdown and to improve the efficiency and the performance of fault detection technique in future Substation Fault Monitoring.

2019 ◽  
Vol 1 (2) ◽  
pp. 94-96
Author(s):  
Lorothy Singkang

Power Substation is the most important unit in the power system, therefore, the monitoring process must be carried out effectively to detect the operation status of the equipment, and the maintenance is necessary for safe operation. Substation faulty such as Dielectric breakdowns, originating from the insulation degradation is still a major issue in the power system (1–3).  Many methods and techniques with intelligence approaches have been developed to provide a better way of fault detection in a substation. However, not many are willing to adopt those techniques by reasoning the high cost of installation and more sensors required to improve localization accuracy (4). Therefore, to reduce cost and increase the speed of detection, this paper presents a 2-element array antenna to perform as a sensor to detect and localize the electric discharges (ED) produced by abnormal radiated electromagnetic activities in substation based on the direction of arriving angle (DOA) received by elements in the array antenna. The radiation patterns obtained were then visualized using software of signal processing based on the normalized Array Factor (AFN). This sensor has shown its efficiency in eliminating the interferer signals at random DOA of  and maximizing the desired signal at DOA of 45Ëš; the identified angle direction from the substation power apparatus.  This sensor has the ability to be steered isotopically and terminate or maximize signals which differ by  or 0.0873 radians of DOAs, simultaneously. Having these abilities allowed this sensor to be a cohesive unit in detecting and localizing the abnormal radiated electromagnetic activities in substation based on the identified DOA thus, make it as a promising preventive approach for substation breakdown and improve the performance in Substation Fault Monitoring.


Author(s):  
Yuqi Pang ◽  
Gang Ma ◽  
Xiaotian Xu ◽  
Xunyu Liu ◽  
Xinyuan Zhang

Background: Fast and reliable fault detection methods are the main technical challenges faced by photovoltaic grid-connected systems through modular multilevel converters (MMC) during the development. Objective: Existing fault detection methods have many problems, such as the inability of non-linear elements to form accurate analytical expressions, the difficulty of setting protection thresholds and the long detection time. Method: Aiming at the problems above, this paper proposes a rapid fault detection method for photovoltaic grid-connected systems based on Recurrent Neural Network (RNN). Results: The phase-to-mode transformation is used to extract the fault feature quantity to get the RNN input data. The hidden layer unit of the RNN is trained through a large amount of simulation data, and the opening instruction is given to the DC circuit breaker. Conclusion: The simulation verification results show that the proposed fault detection method has the advantage of faster detection speed without difficulties in setting and complicated calculation.


2018 ◽  
Vol 17 (4) ◽  
pp. 617-620 ◽  
Author(s):  
Siti Nailah Mastura Zainarry ◽  
Nghia Nguyen-Trong ◽  
Christophe Fumeaux
Keyword(s):  

2018 ◽  
Vol 2 (2) ◽  
pp. 25
Author(s):  
A.A.N. Amrita ◽  
W.G. Ariastina ◽  
I.B.G. Manuaba

Power transformer is very important in electric power system due to its function to raise or lower the voltage according to its designation. On the power side, the power transformer serves to raise voltage to be transmitted to the transmission line. On the transmission side, the power transformer serves to distribute the voltage between the main substations or down to the distribution voltage. On the distribution side, the stresses are channeled to large customers or lowered to serve small and medium customers. As the power transformer is so importance, it is necessary to protect against disturbance, as well as routine and periodic maintenance, so that the power transformer can operate in accordance with the planned time. Some factors that affect the duration of the power transformer is the ambient temperature, transformer oil temperature, and the pattern of load. Load that exceeds the maximum efficiency of the transformer which is 80% of its capacity will cause an increase in transformer oil temperature. Transformer oil, other than as a cooling medium also serves as an insulator. Increasing the temperature of transformer oil will affect its ability as an isolator that is to isolate the parts that are held in the transformer, such as iron core and the coils. If this is prolonged and not handled properly, it will lead to failure / breakdown of insulation resulting in short circuit between parts so that the power transformer will be damaged. PLN data indicates that the power transformer is still burdened exceeding maximum efficiency especially operating in the work area of PLN South Bali Area. The results of this study, on distribution transformers with different loads, in DS 137, DS 263 and DS 363, show that DS 363 transformer with loading above 80% has the shortest residual life time compared to DS 263 and DS 137 which loading less than 80%.


2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Janam Maharjan ◽  
Dong-You Choi

The paper proposes a simple four-element microstrip patch array antenna fed with corporate-series technique. The paper compares the proposed design with four-element antennas fed with only series-fed and corporate-fed microstrip antennas. All three antenna designs use rectangular microstrip patch elements with two insets and slots on both sides of the patch. The patch elements are accompanied by Yagi elements: three director elements and two reflector elements. Through comparison of simulation results, the paper shows that four-element array antenna with combined corporate-series feeding technique performs better compared to antennas with only either series or corporate feeding network. The proposed corporate-series fed antenna achieves better performance with wide frequency bandwidth of 25.04–30.87 GHz and gain of 9.5 dB. The antenna has an end-fire radiation pattern. Overall performance shows that the proposed corporate-series-fed microstrip patch antenna with Yagi elements is suitable for next generation 5G communication.


Sign in / Sign up

Export Citation Format

Share Document