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1.
PMU based adaptive zone settingsof distance relays for protection ofmulti-terminal transmission lines 下载免费PDF全文
Balimidi Mallikarjun Pudi Shanmukesh Dwivedi Anmol Maddikara Jaya Bharata Reddy Dusmanta Kumar Mohanta 《电力系统保护与控制》2018,3(2):126-140
This paper proposes Phasor Measurement Unit (PMU) based adaptive zone settings of distance relays (PAZSD)
methodology for protection of multi-terminal transmission lines (MTL). The PAZSD methodology employs current
coefficients to adjust the zone settings of the relays during infeed situation. These coefficients are calculated in
phasor data concentrator (PDC) at system protection center (SPC) using the current phasors obtained from PMUs.
The functioning of the distance relays during infeed condition with and without the proposed methodology has
been illustrated through a four-bus model implemented in PSCAD/EMTDC environment. Further, the performance
of the proposed methodology has been validated in real-time, on a laboratory prototype of Extra High Voltage
multi-terminal transmission lines (EHV MTL). The phasors are estimated in PMUs using NI cRIO-9063 chassis
embedded with data acquisition sensors in conjunction with LabVIEW software. The simulation and hardware
results prove the efficacy of the proposed methodology in enhancing the performance and reliability of
conventional distance protection system in real-time EHV MTLs. 相似文献
2.
Maloperation of conventional relays is becoming prevalent due to ever increase in complexity of conventional
power grids. They are dominant during power system contingencies like power swing, load encroachment, voltage
instability, unbalanced loading, etc. In these situations, adaptive supervised wide-area backup protection (ASWABP)
plays a major role in enhancing the power system reliability. A balance between security and dependability of
protection is essential to maintain the reliability. This paper proposes multi-phasor measurement units (MPMU)
based ASWABP scheme that can function effectively during faults besides power system contingencies. MPMU is an
extended version of Phasor Measurement Unit (PMU). It is an intelligent electronic device which estimates the
synchronized predominant harmonic phasors (100Hz and 150Hz) along with the fundamental phasors (50Hz) of
three phase voltages and currents with high precision. The proposed ASWABP scheme can detect the fault, identify
the parent bus, determine the faulty branch and classify the faults using MPMU measurements at System Protection
Center (SPC). Based on these MPMU measurements (received at phasor data concentrator (PDC) at SPC) the
appropriate relays will be supervised to enhance the overall reliability of the power grid. Numerous case studies are
conducted on WSCC-9 bus and IEEE-14 bus systems to illustrate the security and dependability attributes of
proposed ASWABP scheme in MATLAB/Simulink environment. Also, comparative studies are performed with the
existing conventional distance protection (Mho relays) for corroborating the superiority of the proposed scheme
regarding security and dependability. Comparative studies have shown that the proposed scheme can be used as
adaptive supervised wide-area backup protection of conventional distance protection 相似文献
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This paper presents an adaptive protection scheme for advanced series compensated (ASC) transmission lines. The scheme is based on Kalman and adaptive Kalman filters. The adaptive scheme utilizes the differences in the transient current signals for faults encountering and not encountering the ASC to determine the fault location with respect to the ASC and the faulted phases. Equations to determine the line impedance to the fault on these lines are developed. The adaptive scheme is tested for faults along and outside the protected line using EMTP simulated data 相似文献
5.
Transposition of power transmission lines represents high costs due to the required transposition towers and also results in low mechanical and electrical strengths. These disadvantages make it desirable not to transpose lines if the resulting unbalances are not adverse. This paper proposes a method to predict the electromagnetic (combination of inductive and capacitive) unbalance of untransposed lines. The method is validated by its application to typical lines under various load conditions and various geometric mean radii. 相似文献
6.
This paper proposes a new noncommunication protection technique for transmission line protection. The technique relies on firstly the detection of fault generated high frequency current transient signals. A specially designed multi-channel filter unit is then applied to the captured signals to extract desired bands of high frequency signals. Comparison between the spectral energies of different bands of the filter outputs determines whether a fault is internal or external to the protected zone. In addition to the saving in costs through negating the need for a communication link, the technique also retains many advantages of the `transient based protection' technology, such as insensitivity to fault type, fault position, fault path resistance and fault inception angle. It is also not affected by CT saturation, the power frequency short-circuit level at the terminating busbar or the precise configuration of the source side networks 相似文献
7.
Joe-Air Jiang Ying-Hong Lin Jun-Zhe Yang Tong-Ming Too Chih-Wen Liu 《Power Delivery, IEEE Transactions on》2000,15(4):1136-1146
Part I of this paper set sets forth theory and algorithms for adaptive fault detection/location technique, which is based on phasor measurement unit (PMU). This paper is Part II of this paper set, A new timing device named “Global Synchronism Clock Generator, GSCG” including its hardware and software design is described in this paper, Experimental results show that the synchronized error of rising edge between the two GSCGs clock is well within 1 ps when the clock frequency is below 2.499 MHz. The measurement results between Chung-Jeng and Chang-Te 161 kV substations of Taiwan Power company by PMU equipped with GSCG is presented and the accuracy for estimating parameters of line is verified. The new developed DFT based method (termed as smart discrete Fourier transform, SDFT) and line parameter estimation algorithm are combined with PMU configuration to form the adaptive fault detector/locator system. Simulation results have shown that SDFT method can extract exact phasors in the presence of frequency deviation and harmonics, The parameter estimation algorithm can also trace exact parameters very well, The SDFT method and parameter estimation algorithm can achieve accuracies of up to 99.999% and 99.99%, respectively. The EMTP is used to simulate a 345 kV transmission line of Taipower System. Results have shown that the proposed technique yields correct results independent of fault types and is insensitive to the variation of source impedance, fault impedance and line loading. The accuracy of fault location estimation achieved can be up to 99.9% for many simulated cases, The proposed technique will be very suitable for implementation in an integrated digital protection and control system for transmission substations 相似文献
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《International Journal of Electrical Power & Energy Systems》2013,44(1):660-669
This paper presents a fault location method suitable for untransposed four-circuit parallel transmission lines using the data available at one end of the line. The proposed method employs an accurate distributed parameter line model that fully accounts for mutual coupling between all the lines and shunt capacitance effects. The fault location algorithms are developed in phase-components, one for the case where the fault is in any one of the circuits, the second for the case where the fault involves any two circuits and the third for the case where the fault involves more than two circuits. The proposed method is tested using the transient data obtained by simulating a 500-kV four-circuit overhead transmission line under different fault conditions. The simulations are done using the software “DIgSILENT PoweFactory”. Results obtained indicate that the method is capable of estimating the fault distance with high accuracy for various fault conditions. Also the robustness of the fault location method is investigated. 相似文献
10.
In the early days of electric power systems, it was the usual practice to have frequent line transpositions to reduce capacitive and inductive unbalances on them. Transposition represents higher line costs owing to the presence of transposition towers and results in lower mechanical and electrical strength. These disadvantages make it desirable not to transpose lines if the resulting unbalances are not adverse.In this paper, the inductive unbalances of a single- and a double-circuit untransposed transmission line are analysed. Effects of loads, of line geometric mean radii and of line ground wire arrangements are included. Results for negative- and zero-sequence components which arise from such unbalances for power systems with typical lines are given and compared with those obtained using methods developed earlier. 相似文献
11.
提出一种新的基于相量测量单元(PMU)的输电线路故障测距的自适应算法。该算法利用PMU装置获得高压线路两端的电压和电流相量,在线计算线路参数,解决了线路实际参数与电力局所提供参数的不同、线路参数在运行过程中的不确定性等问题。采用前置带通滤波器与全波傅氏算法相结合的滤波算法,提取相当精确的突变量基频分量,用于输电线路故障测距。大量的EMTP仿真计算结果和实际系统参数验证结果表明,该测距算法不受系统的运行方式、故障点过渡电阻、故障类型、故障距离等因素的影响,具有很高的测距精度。 相似文献
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Contents A new numerical algorithm for blocking autoreclosure during permanent faults on overhead lines is presented. The fault nature
(permanent or transient) is determined from the voltage signal of faulted and tripped line phase using Least Error Squares
Technique. The algorithm was successfully tested using signals recorded on the real power system. The tests demonstrate the
ability of presented algorithm to determine the secondary arc extinction time.
Received: 22 June 1999 相似文献
übersicht Es wird ein neuer Algorithmus für das Blockieren des selbst?tigen Wiederzuschaltens bei Dauerfehlern auf Freileitungen vorgestellt. Die Art des Fehlers (dauernd oder transient) wird aus dem Spannungssignal der fehlerbehafteten und unterbrochenen Leitungsphase mittels einer Technik der kleinsten Fehlerquadrate ermittelt. Mit aufgezeichneten Signalen von einem realen Energieversorgungssytem wurde der Algorithmus erfolgreich getestet. Die Ergebnisse verdeutlichen die F?higkeit des vorgestellten Verfahrens, die L?schzeit des sekund?ren Lichtbogens zu ermitteln.
Received: 22 June 1999 相似文献
14.
M. JannatiB. Vahidi S.H. HosseinianS.M. Ahadi 《International Journal of Electrical Power & Energy Systems》2011,33(3):639-646
In modern interconnected power systems, nearly 80% of faults in high voltage transmission lines are intrinsically transient. The necessity of rapid fault clearing has resulted in fast development of protection equipments. Moreover, need for reliable supply of loads has led to improvements in single phase auto-reclosing equipments. In this paper, a novel and efficient method is proposed that leading to improved performance and efficiency of single phase auto-reclosing. In the case of occurrence of permanent faults, the proposed yardstick is accurate and authentic to diagnose fault type (transient or permanent). To validate accuracy and authenticity of the proposed method, a 400 kV transmission system is simulated using EMTP software and results are presented. 相似文献
15.
《Electric Power Systems Research》2005,73(2):107-112
The paper describes a new technique for protecting asymmetrical and symmetrical EHV three terminal lines. One relay is installed to recognize a blocking or a tripping terminal at the terminal that uses two circuits. The polarity of fault current is detected at each end using the Haar wavelet function. A communication channel is used to receive the status of the polarity at each end. A gate logic circuit at each end is used to issue final decision based on the collected polarities. The problem areas of the current protective techniques are solved. No voltage signal is used. An EMTP/ATP simulator is used to demonstrate the performance of the proposed technique. 相似文献
16.
This paper presents a new adaptive fault protection scheme for transmission lines using synchronized phasor measurements. The work includes fault detection, direction discrimination, classification, and location. Both fault-detection and fault-location indices are derived by using two-terminal synchronized measurements incorporated with distributed line model and modal transformation theory. The fault-detection index is composed of two complex phasors and the angle difference between the two phasors determines whether the fault is internal or external to the protected zone. The fault types can be classified by the modal fault-detection index. The proposed scheme also combines online parameter estimation to ensure protection scheme performance and achieve adaptive protection. Extensive simulation studies show that the proposed scheme provides a fast relay response and high accuracy in fault location under various system and fault conditions. The proposed method responds very well with regards to dependability, security, and sensitivity (high-resistance fault coverage). 相似文献
17.
Joe-Air Jiang Jun-Zhe Yang Ying-Hong Lin Chih-Wen Liu Jih-Chen Ma 《Power Delivery, IEEE Transactions on》2000,15(2):486-493
An adaptive fault detection/location technique based on a phasor measurement unit (PMU) for an EHV/UHV transmission line is presented. A fault detection/location index in terms of Clarke components of the synchronized voltage and current phasors is derived. The line parameter estimation algorithm is also developed to solve the uncertainty of parameters caused by aging of transmission lines. This paper also proposes a new discrete Fourier transform (DFT) based algorithm (termed the smart discrete Fourier transform, SDFT) to eliminate system noise and measurement errors such that extremely accurate fundamental frequency components can be extracted for calculation of fault detection/location index. The EMTP was used to simulate a high voltage transmission line with faults at various locations. To simulate errors involved in measurements, Gaussian-type noise has been added to the raw output data generated by EMTP. Results have shown that the new DFT based method can extract exact phasors in the presence of frequency deviation and harmonics. The parameter estimation algorithm can also trace exact parameters very well. The accuracy of both new DFT based method and parameter estimation algorithm can achieve even up to 99.999% and 99.99% respectively, and is presented in Part II. The accuracy of fault location estimation by the proposed technique can achieve even up to 99.9% in the performance evaluation, which is also presented in Part II 相似文献
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Simi P. Valsan K.S. Swarup 《International Journal of Electrical Power & Energy Systems》2009,31(7-8):379-388
This paper presents a high speed, computationally efficient scheme for protection of transmission lines. The relay logic consists of three parts: directional protection, fault classification and fault location. Wavelet transform is used for extracting information from the fault transients and only the first level high frequency details of the voltages and currents are used. Proposed protection logic compares the directional signals from both terminals to discriminate between faults inside and outside the zone of interest. Fault classification is achieved using local terminal current information. An estimate of the location of the faults is obtained utilizing single faulted phase current information from both terminals. The logic is deterministic and can work reliably in the presence of fault resistance, load variation and CT saturation. The validity of the proposed logic was exhaustively tested by simulating various types of faults on a four bus meshed system modeled in EMTP/ATP. 相似文献
20.
This paper presents an adaptive transmission line protection scheme based on synchronized phasor measurement units. This scheme uses the positive-sequence voltage and current phasors at both ends of a transmission line to determine the parameter of the transmission line and the location of a fault on the transmission line. This scheme can be used for the protection of both single- and double-circuit transmission lines. This scheme is also robust against power swing conditions. A novel adaptive single pole auto re-closer is introduced based on the proposed scheme due to its capability of differentiating transient and permanent faults. System simulation studies show that the proposed scheme is able to operate fast and accurately for transmission line protection. 相似文献