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The paper presents an example of modeling high-voltage line with classical columns and pillars compacted with the same lines and testing out the model in the programming tool DIgSILENT with actual measured data for Single Line to Ground Fault with the use of ARs. The parameters of the classical and compacted 400 kV transmission line are entered into the model in the example of 400 kV line Tuzla 4...
In this paper, the evaluation of the concept of impedance differential scheme for long transmission line protection is presented. Using the voltages and currents of both line ends, the differential impedance is calculated. Capacitive charging current which constitutes the main drawback of current differential protection is eliminated in presented protection method. What is more, the advantage of presented...
The scaled down laboratory model of the modelled line using air-core inductor and shunt capacitor has been practically designed, experimented and its performance parameters are evaluated. The protection scheme using three-step zone protection is achieved using a relay operated by an ARM Microcontroller. The Microcontroller is used as a controller which actuates the relay. This paper has been done...
This contribution addresses the statistical assessment of cables performance via the precise computation of S-parameters statistics. These data are derived by Lagrange interpolation of a given set of measurements assuming uncertainties around terminal load. The proposed philosophy provides useful information to characterize systems under uncertain constraints.
In this paper, a modified enhanced transmissionline theory taking into account higher-order modes is described. The new equations are based on the correction of the per-unit-length parameters that become frequency dependent and contain the radiation resistance. In particular, the per-unit-length resistance takes into account this radiation resistance and an additional resistance proportional to the...
This paper identifies the monotonic and linear relationship between transition resistance and line impedance. Based on this concept, an algorithm is proposed to calculate the reactance of transition resistance in different points of the transmission line, and search for the fault location as that point where the reactance value is zero. This approach can eliminate the effect of high resistance grounding...
This paper presents a new impedance based fault location method in the case of phase to phase and three phase faults. This method utilized the measured impedance by distance relay and super imposed current factor, which is the ratio of post-fault current to super imposed current, to discriminate the fault position on the line. This method is robust against the fault resistance. The presented method...
This paper presents an algorithm for locating faults on series-compensated transmission lines. The algorithm suits to both single- and double-circuit series-compensated lines. Use of two-end synchronized measurements of currents accomplished by current differential protective relays with additional incorporation of the locally measured three-phase voltage is considered. More superior solution with...
A novel phase selector is proposed based on the multi-parameter comparison of fault components. Each of three phases is used as the reference phase in turn to calculate the positive sequence component and the sum of the zero and negative sequence components. The phase difference between the positive sequence component and the sum of the zero and negative sequence components is calculated under three...
In order to overcome the distortion problem of CCD driving signals caused by signal transmission, the detail implementation of transmission of high-speed CCD driving signals based on transmission line theory is discussed. The CCD driving signals are critical to the CCD to produce high quality images. In high speed application these drivers will occupy more circuit board areas and can not be put very...
A measurement system based on FMCW radar principle for fast inhomogeneity identification of a transmission line in short range application is presented. In comparison with traditional TDR method where the analysis of reflected waveform is directly processed in time domain, FMCW radar principle converts the analysis work into frequency domain and greatly reduces the hardware requirements consequently...
This paper presents an adaptive distance protection in the presence of Static Synchronous Series Compensator (SSSC), one of the series connected Flexible Alternating Current Transmission System (FACTS) devices. The presence of SSSC on a transmission line has a great influence on the measured impedance at the relaying point. The measured impedance itself depends on the power system structural conditions,...
Protection system is one of the important parts of the power system. The protection system can be accepted if and only if it is efficient one and realize some requirements. For Protection of transmission line three stepped distance protection can provide remote backup protection to transmission line by zone 2 and zone 3, but during the calculation of operation setting for different protection zones...
Through-hole vias made of multiwall carbon nanotubes (MWCNTs) are simulated using the multiconductor and equivalent single conductor models. The circuit approach is developed in order to define an equivalent lumped-parameter SPICE-model. Different expressions of the p.u.l. damping quantum resistance are considered and their impact on the prediction of the via performance at high frequency is discussed...
Analysis and synthesis of the new Class-E3F2 power amplifier (PA) are presented in this paper. The proposed circuit offers means to alleviate some of the major issues faced by existing Class-EF and Class-EF2 PAs, such as (1) substantial power losses due to parasitic resistance of the large inductor in the Class-EF load network, (2) unpredictable behaviour of practical lumped inductors and capacitors...
An accurate algorithm for locating faults on a series-compensated line is presented. This algorithm can be applied with current differential protective relays since two-end currents and one-end voltage are utilized as the fault locator input signals. The algorithm applies two subroutines and the procedure for indicating the valid subroutine. The algorithm has been evaluated using the fault data of...
This paper presents a modified distance protection in the presence of Static Synchronous Series Compensator (SSSC), one of the series connected Flexible Alternating Current Transmission System (FACTS) devices. The presence of SSSC on a transmission line has a great influence on the measured impedance at the relaying point. The measured impedance itself depends on the power system structural conditions,...
This paper presents a modified distance protection due to the presence of STATic synchronous COMpensator (STATCOM), one of the shunt connected Flexible Alternating Current Transmission System (FACTS) devices. The presence of STATCOM on a transmission line has a great influence on the measured impedance at the relaying point. The measured impedance itself depends on the power system structural conditions,...
This paper proposes a protection scheme for transmission lines based on nature frequency of fault-generated travelling wave. The fault component of current signals are first computed and decoupled into their modal components, and then the mode spectrums are computed by FFT to extra the fundamental frequency of nature frequencies, through comparing the fundamental frequency at both ends of lines to...
This paper discusses the impact of a directly connected load to transmission lines, without switching and protective facilities, on distance relays at the line ends, by means of presenting the measured impedance at the relaying point and the distance relay ideal tripping characteristic. The measured impedance at the relaying point is affected by several factors, including the line structural and pre-fault...
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