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We report the first successful real-time superchannel trials up to 5.6Tb/s over 359km and 2Tb/s over a live 727km link using 64GBaud flexible-rate transponders, demonstrating long term error-free performance and fast capacity turn-up of ∼2Tb/min.
Sustained oscillations are one of major stability concerns of a power system operator. In order to take effective remedial reactions, it is preferred to detect sustained oscillations at their early stage. Previously, self-coherence spectra were used to detect sustained oscillations using phasor measurement unit (PMU) data. This paper proposes a hypothesis test using a bootstrap method to set up a...
MATLAB programs based on Geometrical Optics (GO) theory were used to calculate the standard uncertainty introduced by the ripple of Anechoic Chamber (AC) in OTA (Over The Air) test. The same method was also used to study the influence of various factors, including high directivity measurement antennas and high performance absorbers. In addition, we likewise found that support structures should be...
With 20μm diameter PCC wire, spherical (well-shaped) free-air balls (FABs) were obtained in both forming gas and N2 at flow rates between 0.25–0.75 l/min and 0.4–0.5 l/min, respectively. With Cu wire, in comparison, sperical FAB are obtained in forming gas with flow rates between 0.25 and 0.5 l/min while in N2 gas, FABs are always pointed or golf-clubbed (mis-shaped). Using a shielding gas with Au...
This paper presents the idea and initial results of building decision trees (DTs) for detecting and identifying various transient dynamic events using the characteristic ellipsoid method. In this paper, the objective is to determine fault types, fault locations and clearance times in the system using DTs based on ellipsoids surrounding system transient responses in the system operating parameter space...
Balancing Authorities are responsible for managing their system imbalances including deviations caused by the integration of variable generation resources. As wind and solar penetration levels increase, the challenges of managing power variations also increase. Working independently, balancing areas (BAs) with limited regulation and load following capacity and high wind power penetration would face...
In this paper, the transmission properties of three 1-row periodic rod arrays, namely perfect conductor array, copper array with surface conductivity and single wall carbon nanotube (SWCNT) array with quantum conductivity, are investigated. MoM with special algorithms of Toeplitz matrices is employed. It is found that, due to the quantum effects, SWCNT array can transmit energy in a lower frequency...
A method of estimating a power system's electromechanical mode shape and coherence from time synchronized phasor measurements is presented. The approach uses a parametric estimate of the transfer function (TF) between signals at different buses throughout the power system. The relationship between the TF and mode shape and coherence is reviewed. A non-causal autoregressive exogenous (ARX) model is...
Power system mode shapes are a key indication of how dynamic components participate in low-frequency oscillations. Traditionally, mode shapes are calculated from a linearized dynamic model. For large-scale power systems, obtaining accurate dynamic models is very difficult. Therefore, measurement-based mode shape estimation methods have certain advantages, especially for the application of real-time...
Measurement-based mode-estimation methods are utilized to estimate electromechanical modes of a power system using phasor measurement units (PMU) data. These methods need to extract a certain amount of information before they can provide a useful mode estimation. Traditionally, the information is gathered solely from measurement data. A priori mode information from other resources (e.g. model eigenvalue...
When analyzing the electromechanical dynamic properties of power-system field-measurement data using signal processing techniques, it is often useful to identify and remove the slow trends within the data. This paper proposes an iterative non-linear trend identification algorithm. The proposed method adapts the upper and lower envelope idea proposed by empirical mode decomposition (EMD) method to...
This paper presents an innovative solution to power quality problems using power quality-improving (PQI) appliances. PQI appliances conduct currents that supplement and correct the sum of the other load currents within a premise. From the utility side, the premise housing a PQI appliance thus becomes an improved, if not ideal, utility customer. The PQI appliance improves both harmonic power quality...
Near real-time measurement-based electromechanical-mode estimation offers considerable potential for many future power-system operation and control strategies. Recent research has investigated the use of low-level pseudo random noise (PRN) probing signals injected into power systems to estimate the low-frequency electromechanical modes. Because of the random nature of a power system, estimating the...
Near real-time measurement-based electromechanical-mode estimation offers considerable potential for many future power-system operation and control strategies. Recent research has investigated the use of low-level pseudo random noise (PRN) probing signals injected into power systems to estimate the low-frequency electromechanical modes. Because of the random nature of a power system, estimating the...
In this paper, we attempt to answer the following question with systematic computer simulations: for the same validation error rate, does the size of a feedforward neural network matter? This is related to the so-called Occam's Razor, that is, with all things being equal, the simplest solution is likely to work the best. Our simulation results indicate that for the same validation error rate, smaller...
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