Reed-Switch Short-Circuit Protection with Zero-Sequence Current Filter, Self-Diagnostics and Duplication

2021 ◽  
Author(s):  
Bauyrzhan Mashrapov ◽  
Assemgul Zhantlessova
Keyword(s):  
Short Circuit ◽  
Reed Switch ◽  
Zero Sequence

scholarly journals Analysis of Effective Three-Level Neutral Point Clamped Converter System for the Bipolar LVDC Distribution

Electronics ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 691 ◽  
Author(s):  
Ju-Yong Kim ◽  
Ho-Sung Kim ◽  
Ju-Won Baek ◽  
Dong-Keun Jeong
Keyword(s):  
Distribution System ◽  
Low Voltage ◽  
Balance Control ◽  
Short Circuit ◽  
Renewable Energy Sources ◽  
Neutral Point ◽  
Extreme Load ◽  
Zero Sequence ◽  
Zero Sequence Voltage ◽  
Short Circuit Condition

Low-voltage direct current (LVDC) distribution has attracted attention due to increased DC loads, the popularization of electric vehicles, energy storage systems (ESS), and renewable energy sources such as photovoltaic (PV). This paper studies a ±750 V bipolar DC distribution system and applies a 3-level neutral-point clamped (NPC) AC/DC converter for LVDC distribution. However, the 3-level NPC converter is fundamental in the neutral-point (NP) imbalance problem. This paper discusses the NP balance control method using zero-sequence voltage among various solutions to solve NP imbalance. However, since the zero-sequence voltage for NP balance control is limited, the NP voltage cannot be controlled to be balanced when extreme load differences occur. To maintain microgrid stability with bipolar LVDC distribution, it is necessary to control the NP voltage balance, even in an imbalance of extreme load. In addition, due to the bipolar LVDC distribution, the pole where a short-circuit condition occurs limits the short current until the circuit breaker operates, and a pole without a short-circuit condition must supply a stable voltage. Since the conventional 3-level NPC AC/DC converter alone cannot satisfy both functions, an additional DC/DC converter is proposed, analyzed, and verified. This paper is about a 3-level NPC AC/DC converter system for LVDC distribution. It can be used for the imbalance and short-circuit condition in bipolar LVDC distribution through the prototype of the 300 kW 3-level NPC AC/DC converter system and experimented and verified in various conditions.

scholarly journals Detection of Partial Demagnetization Faults in Five-Phase Permanent Magnet Assisted Synchronous Reluctance Machines

Energies ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 3496
Author(s):  
Carlos Candelo-Zuluaga ◽  
Jordi-Roger Riba ◽  
Dinesh V. Thangamuthu ◽  
Antoni Garcia
Keyword(s):  
Permanent Magnet ◽  
Permanent Magnets ◽  
Short Circuit ◽  
Detection Methods ◽  
Element Analysis ◽  
Field Weakening ◽  
Synchronous Reluctance Motor ◽  
Harmonic Content ◽  
Zero Sequence ◽  
Demagnetization Faults

This paper analyzes partial demagnetization faults in a five-phase permanent magnet assisted synchronous reluctance motor (fPMa-SynRM) incorporating ferrite permanent magnets (PMs). These faults are relevant because of the application of field weakening, or due to high operating temperatures or short circuit currents, the PMs can become irreversibly demagnetized, thus affecting the performance and safe operation of the machine. This paper proposes fault indicators to detect such fault modes with low demagnetization levels between 5.0% to 16.7% relative demagnetization. Four partial demagnetization fault detection methods are tested, which are based on the analysis of the harmonic content of the electromotive force (EMF) under no load conditions, the harmonic content of the line currents, the harmonic content of the zero-sequence voltage component (ZSVC) and the analysis of the power factor (PF). This work also compares the sensitivity and performance of the proposed detection methods. According to the fault indicators proposed in this paper, the results show that the analysis of the EMF, ZSVC and PF are the most sensitive detection methods. Experimental results are presented to validate finite element analysis (FEA) simulations.

Research on Electrical Characteristics of a Novel Balance Transformer with Asymmetrical Winding

2014 ◽  
Vol 536-537 ◽  
pp. 1523-1526 ◽  
Author(s):  
Yong Sheng Li ◽  
Yi Fa Sheng ◽  
Kai Yi Zhang ◽  
Bo Fan
Keyword(s):  
Magnetic Force ◽  
Short Circuit ◽  
Neutral Current ◽  
Force Balance ◽  
Analysis Method ◽  
Systematic Analysis ◽  
Negative Sequence ◽  
Transfer Equations ◽  
Zero Sequence ◽  
Negative Sequence Current

For problems of zero sequence current and negative sequence current of traction transformer in Electrified Railway, a novel balance transformer with asymmetrical windings was presented. By a systematic analysis method based on the magnetic force balance equations, winding connection equations, output-port equations and voltage transfer equations, the current relationships of the primary windings and secondary windings, the balance condition and the short circuit impedances (when the neutral current in the primary side is zero) were deduced, and the electric characteristics of the balance transformer was analyzed. Through the experimental model of balance transformer in simulation platform based on Matlab/Simulink, the electric characteristics of balance transformer and change law of zero sequence current and negative sequence current in different mode were researched. Correctness and feasibility of the theoretical analysis are verified through the simulation experiment.

Diagnosis of a turn-to-turn short circuit in power transformers by means of zero sequence current analysis

2004 ◽  
Vol 69 (2-3) ◽  
pp. 321-329 ◽  
Author(s):  
Guzmán Dı́az González ◽  
Javier Gómez-Aleixandre Fernández ◽  
Pablo Arboleya Arboleya
Keyword(s):  
Short Circuit ◽  
Power Transformers ◽  
Current Analysis ◽  
Zero Sequence

scholarly journals Analisis Pengaruh Kompensasi Impedansi Urutan Nol (Kzn) terhadap Kehandalan Sistem Proteksi Rele Jarak (Distance Relay) pada Penghantar Harapan Indah di Gardu Induk Plumpang

2021 ◽  
Vol 4 (1) ◽  
pp. 1
Author(s):  
Deni Almanda ◽  
Juniyanto Juniyanto
Keyword(s):  
Single Phase ◽  
Short Circuit ◽  
Relay Protection ◽  
Protection System ◽  
Distance Relay ◽  
Two Phase ◽  
Test Tool ◽  
Three Phase ◽  
Zero Sequence ◽  
Short Circuit Fault

Pada saat terjadi gangguan hubung singkat di saluran transmisi Gardu Induk Plumpang, rele jarak berfungsi sebagai proteksi utama. Penelitian ini bertujuan untuk mengetahui pengaruh kompensasi impedansi urutan nol (kzn) terhadap kehandalan sistem proteksi rele jarak (distance relay) pada penghantar harapan indah di Gardu Induk Plumpang. Setting rele jarak yang didapatkan dari PT PLN (Persero) UPT Pulogadung disimulasikan menggunakan alat uji Omicron. Hasil simulasi gangguan hubung singkat satu fasa, gangguan hubung singkat dua fasa, dan gangguan hubung singkat tiga fasa menggunakan setting lama Z1 = 2.58 Ω, Z2 = 3.87 Ω, dan Z3 = 7.30 Ω, kZn = 0.93 Ω < -0.4° rele jarak tidak bekerja selektif, maka dilakukan resetting. Hasil resetting rele jarak yaitu Z1 = 2.58 Ω, Z2 = 3.87 Ω, dan Z3 = 7.30 Ω, kZn = 0.68 Ω < -0.6°. Setelah dilakukan resetting dan disimulasikan gangguan hubung singkat satu fasa, gangguan hubung singkat dua fasa, dan gangguan hubung singkat tiga fasa, rele jarak bekerja secara handal. Kesimpulannya kZn dapat mempengaruhi kehandalan sistem proteksi rele jarak pada penghantar harapan indah di Gardu Induk Plumpang.In the event of a short circuit in the transmission line of the Plumpang Substation, the distance relay serves as the main protection. This study aims to determine the effect of zero sequence impedance compensation (kzn) on the reliability of the distance relay protection system at the Harapan Indah conductor at the Plumpang Substation. The distance relay setting obtained from PT PLN (Persero) UPT Pulogadung was simulated using the Omicron test tool. Simulation results of single phase short circuit, two phase short circuit, and three phase short circuit using the old setting Z1 = 2.58 Ω, Z2 = 3.87 Ω, and Z3 = 7.30 Ω, kZn = 0.93 < -0.4° relay distance does not works selectively, then resetting is done. The results of resetting the distance relay are Z1 = 2.58 Ω, Z2 = 3.87 Ω, and Z3 = 7.30 Ω, kZn = 0.68 < -0.6°. After resetting and simulating single-phase short circuit, two phase short circuit, and three phase short circuit fault, the distance relay works reliably. In conclusion, kZn can affect the reliability of the distance relay protection system on the beautiful hope conductor at the Plumpang Substation.

scholarly journals Construction and Modeling of Multi-Circuit Multi-Voltage HVAC Transmission Lines

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 421
Author(s):  
Agnieszka Dziendziel ◽  
Henryk Kocot ◽  
Paweł Kubek
Keyword(s):  
Transmission Lines ◽  
Short Circuit ◽  
Electrical Energy ◽  
Network Capacity ◽  
Mechanical Analysis ◽  
Symmetric Model ◽  
Correct Operation ◽  
Overhead Lines ◽  
Zero Sequence ◽  
The Impact

A transmission network’s main objective is to continuously supply electrical energy to consumers. This article presents an analysis of the use of multi-circuit, multi-voltage overhead lines as a compromise between ensuring the system’s safe operation by increasing the transmission network capacity and managing the constraints related to its expansion. The considerations presented in this work include the construction of such lines, their operation, and modeling aspects. As part of the study, the potential for improving the environmental conditions around the lines is discussed in terms of the necessary area for their construction and the peak electromagnetic field strength in their vicinity. We also present a mechanical analysis of stress and sag coordination in the individual circuits of these lines. Then, we detail the method for determining the electrical parameters of multi-voltage lines’ series impedances and capacitance. Specific attention is given to the possibility of zero-sequence voltage that occurs in the systems despite the symmetric supply and load of circuits—especially in the circuits with the lowest voltages—that result from the line’s geometric asymmetry. We evaluate the impact of the line’s geometric asymmetry on the power system’s correct operation by determining the asymmetry factors. Finally, the accuracy of using a simplified symmetric model for lines with various geometric asymmetries is analyzed by studying the error of the short-circuit currents.

scholarly journals The influence of changing resistance on the determination accuracy of short circuits in power lines

2021 ◽  
Vol 288 ◽  
pp. 01091
Author(s):  
Serdar Nazarov ◽  
Gurbangulych Kelov ◽  
Berdimyrat Gochyev
Keyword(s):  
Single Phase ◽  
Short Circuit ◽  
Stable State ◽  
Short Circuit Current ◽  
Scientific Work ◽  
Electric Power System ◽  
Electrical Networks ◽  
Zero Sequence ◽  
Short Circuits ◽  
Maintenance Personnel

In high-voltage electrical networks, the occurrence of short circuits leads to forced interruptions in the power supply of large consumers and disruptions in intersystem communications. More than 65% of all types of occurring short circuits are single-phase short circuits [1]. In a single-phase short circuits (SPSC), a change in the zero sequence resistance (ZSR) especially significantly affects the inaccuracy in detection of damage sites (DDS). When choosing DDS methods, preference is given to remote methods according to the parameters of the emergency conditions (PEC), which are recorded by special instruments or determined from the oscillograms of emergency conditions. The use of modern microprocessor-based relay protection and automation devices (RPA) [26] or emergency event recorders allow viewing the oscillograms of emergency events. In a branched 110 kV network with a complex configuration, the DDS accuracy is influenced by a change in the ZSR. Averaging of specific parameters often leads to erroneous results. The choice of one value from the oscillograms puts the maintenance personnel in difficulty. In the scientific work, the influence of changes in the ZSR on the accuracy of the DDS is considered. The changes in the ZSR are influenced by the position of the on-load voltage regulator (OLTC) switches of transformers with a grounded neutral. In the work, for a more accurate record of the specific parameters of the network, a calculation program has been compiled, which allows making changes in the calculated specific parameters of the network. To determine the short-circuit current from the oscillograms, it is proposed to determine the stable state of accidents in which the current value will be approximately the same. The analysis of the oscillograms of SPSC in 110-220 kV networks in the southern part of the electric power system of Turkmenistan has been carried out.

scholarly journals ANALISIS GANGGUAN HUBUNG SINGKAT PADA JARINGAN PEMAKAIAN SENDIRI PLTU BOLOK PT. SMSE (IPP) UNIT 3 DAN 4 MENGGUNAKAN SOFTWARE ETAP 12.6.0

2019 ◽  
pp. 79-88
Author(s):  
Agusthinus S. Sampeallo ◽  
Nursalim Nursalim ◽  
Patrisius J. Fischer
Keyword(s):  
Power Plant ◽  
Circuit Simulation ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Electric Power System ◽  
Feed Water ◽  
Steam Power ◽  
Steam Power Plant ◽  
Zero Sequence ◽  
Short Circuit Fault

Bolok Steam Power Plant has its own 6.3 kV usage network to service loads such as Feed Water Pump and Circulating Pump Feed. This self-use network is expected to supply unit loads at the Bolok coal-fired steam power plant without any interference. The presence of disturbances such as short circuit in the electric power system can cause problems such as damage to electrical equipment and the emergence of a power outage. Therefore problems that arise like this require an analytical study to determine the short circuit current that will occur while reducing the consequences that arise. This study aims to determine the largest short circuit fault current with the help of ETAP 12.6.0 software. Short circuit simulation results with ETAP 12.6.0 will be compared with manual calculations based on positive, negative and zero sequence impedance values from the point of disturbance location. Based on the results of the research that has been done, it is known that the type of two-phase short circuit interference to the ground is the largest type of interference, which is equal to 10,615 kA on the generator bus. Whereas for the smallest type of short circuit interference is the type of disturbance one phase to the ground that is equal to 3,967 kA on the OutGoing II bus. From the results of the simulations conducted, it can also be seen that changes in the value of short circuit fault currents are affected by changes in the number of operating loads. The more load that operates the positive and negative sequence impedance the smaller and the value of the short circuit current will be greater, while the zero sequence impedance does not affect the amount of load operating, as well as the opposite.

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