Stipulation of Facts, \u3cem\u3eTVA v. Hill et al\u3c/em\u3e, Civil Action No. 3-76-48

Stipulation of facts agreed upon by the plaintiffs and defendants in the case of TVA v. Hill et al in the United States District Court for the Eastern District of Tennessee, Northern Division

Open source cable models for EMI simulations

This paper describes the progress of work towards an Open Source software toolset suitable for developing Spice based multi-conductor cable models. The issues related to creating a transmission line model for implementation in Spice which include the frequency dependent properties of real cables are presented and the viability of spice cable models is demonstrated through application to a three conductor crosstalk model. Development of the techniques to include models of shielded cables and incident field excitation has been demonstrated

Background voltage distortion and percentage of nonlinear load impacts on the harmonics produced by a group of personal computers

The penetration of nonlinear loads on power systems increases distortion levels and can cause severe problems to power systems. Many factors affect the degree of generated harmonics including the background voltage distortion and percentage of nonlinear load to the total load. Hence, the purpose of this paper is to investigate and accurately quantify the effects of these two factors on the harmonics produced by a group of Personal Computers (PCs). Experimental measurements and computer simulations are performed to confirm the observations

A double end fault location technique for distribution systems based on fault-generated transients

This paper presents a fault location technique for distribution systems. It is a two end impedance based technique that uses the fault generated transients to estimate the fault distance over a broad range of frequencies. Then, curve fitting is applied to find the final estimated fault distance. Firstly, the paper introduces the method for the system represented as a lumped RL model. Then, generalized to consider the distribution line capacitance. The technique accounts for presence of loading taps, heterogeneous feeder sections, single phase, two phase and three phase loads and unbalance in distribution system. Single line to ground, line to line, and three phase faults are considered at different fault resistance values up to 100 Ω. Also, the effect of fault inception angle and resolution of analogue to digital converter is investigated. IEEE 34 nodes system is used to evaluate the proposed method

Fast fault location scheme for distribution systems based on fault transients

This paper presents a combined double-end and single-end fault locator for distribution systems. The technique lies under the impedance based category and uses the fault generated high frequency components to locate the faults. The combination of double-end and single-end allows the method to discriminate between faults on the main feeder and those on laterals. Also, the method only requires a short data window as it depends on the high frequency components. The evaluation of the method considers different system and fault parameters e.g. loading taps, loading unbalance, fault type and fault resistance. To validate the proposed technique, the IEEE 34 nodes system is used to simulate different test cases

Real time parameter estimation for power quality control and intelligent protection of grid-connected power electronic converters

This paper presents a method to identify power system impedance in real-time using signals obtained from grid- connected power electronic converters. The proposed impedance estimation has potential applications in renewable/distributed energy systems, STATCOM, and solid state substations. The method uses wavelets to analyze transients associated with small disturbances imposed by power converters and determine the net impedance back to the source. A data capture period of 5ms is applied to an accurate impedance estimation which provides the possibility of ultra fast fault detection (i.e. within a half cycle). The paper describes how the proposed method would enhance the distributed generation operation during faults

Open source cable models for EMI simulations

This paper describes the progress of work towards an Open Source software toolset suitable for developing Spice based multi-conductor cable models. The issues related to creating a transmission line model for implementation in Spice which include the frequency dependent properties of real cables are presented and the viability of spice cable models is demonstrated through application to a three conductor crosstalk model. Development of the techniques to include models of shielded cables and incident field excitation has been demonstrated

Impedance sensitive STATCOM control for systems supported by renewable generation

Reactive power control is known to be an effective means of controlling voltage; however, for optimal performance, the system reactance must be known. Power systems with high re-newable energy penetration have been known to have voltage stability issues. To further complicate this issue, distributed renewable sources are likely to have an effect on the local sys-tem impedance. As a result, connection and disconnection of such sources is likely to result in significant changes in system impedance. In this paper, impedance estimation is used to dy-namically tune the controllers of a STATCOM so that consis-tent dynamic performance may be obtained. The method has been verified through simulation and through laboratory-based experimentatio

Influence of an inverter based DG on a double-ended fault location scheme

This paper describes the influence of Distributed Generation (DG) on a double ended fault location based on measuring the high frequency fault transients. The additional non-fundamental frequency current components from DG will influence the accuracy of an impedance based fault location technique based on non-fundamental frequencies. A double-ended impedance based fault location technique that utilizes the high frequency content (up to 5 kHz) is studied. The study showed that double-ended method is still able to locate a fault with a maximum error of 4% compared to the case without DG which showed a percentage error up to 2%

Method of efficiently predicting the conducted emissions of multiple VSCs

Various types of power converters including Voltage Source Converters (VSCs) have been known to produce conducted emissions. The net effect of simultaneously operating multiple VSCs is non-linear and this makes the prediction of the emission level more difficult. This paper presents an efficient method that can be used to predict conducted emissions of multiple VSCs in the presence of various uncertainties. It utilizes the Univariate Dimension Reduction (UDR) and the Bivariate Dimension Reduction (BDR) technique to predict the conducted emission level of multiple VSCs