Evaluation of Impact from Ripple and Transient Phenomena in the LHC Dipole Strings

Based on measurements of the A.C. electrical characteristics of prototype magnets, synthesized computer models of the principal, individual, superconducting magnetic elements of the Large Hadron Collider have been elaborated. The models constitute the basic elements for the determination of the transfer functions of the magnet chains. This tool provides the possibility to evaluate the resonance spectrum of the chains and to determine the needs for additional damping. Results of the analysis of transmission line effects in the LHC main dipole chains are presented. In particular, data from ripple calculations and ramping studies are discussed. Computer simulations of the quench protection circuit provide information about the transient phenomena occurring in the dipole chains during normal operation of the fast de-excitation switches and under abnormal conditions

Dynamic Harmonic Domain Modeling of Flexible Alternating Current Transmission System Controllers

Flexible alternating current transmission system (FACTS) and multi-line FACTS controllers play an important role in electrical power transmission systems by improving power quality and increasing power transmission capacity. These controllers are nonlinear and highly complex when compared to mechanical switches. Consequently, during transient conditions, it is very difficult to use conventional time and frequency domain techniques alone to determine the precise dynamic behavior of the harmonics introduced into the system by these controllers. In particular, the time-varying nature of the harmonic components is not captured by these techniques. The contribution of this work to the state of power systems analysis is the development of new models for seven important and widely-used FACTS controllers (static synchronous series compensator (SSSC), unified power flow controller (UPFC), fixed capacitor-thyristor controlled reactor (FC-TCR), thyristor controlled switched capacitor (TCSC), generalized unified power flow controller (GUPFC), interline power flow controller (IPFC), and generalized interline power flow controller (GIPFC)) using a technique called the dynamic harmonic domain method. These models are more accurate than existing models and aid the power systems engineer in designing improved control systems. The models were simulated in the presence of disturbances to show the evolution in time of the harmonic coefficients and power quality indices. The results of these simulations show the dynamic harmonic response of these FACTS controllers under transient conditions in much more detail than can be obtained from time-domain simulations, and they can also be used to analyze system performance under steady-state conditions. Some of the FACTS controllers\u27 models discussed in this work have a common DC link, but for proper operation, the DC side voltage must be held constant. The dynamic harmonic domain method was applied to the FACTS devices to design feedback controllers, which help in maintaining constant DC

Dynamic Harmonic Domain Modeling of Flexible Alternating Current Transmission System Controllers

Flexible alternating current transmission system (FACTS) and multi-line FACTS controllers play an important role in electrical power transmission systems by improving power quality and increasing power transmission capacity. These controllers are nonlinear and highly complex when compared to mechanical switches. Consequently, during transient conditions, it is very difficult to use conventional time and frequency domain techniques alone to determine the precise dynamic behavior of the harmonics introduced into the system by these controllers. In particular, the time-varying nature of the harmonic components is not captured by these techniques. The contribution of this work to the state of power systems analysis is the development of new models for seven important and widely-used FACTS controllers (static synchronous series compensator (SSSC), unified power flow controller (UPFC), fixed capacitor-thyristor controlled reactor (FC-TCR), thyristor controlled switched capacitor (TCSC), generalized unified power flow controller (GUPFC), interline power flow controller (IPFC), and generalized interline power flow controller (GIPFC)) using a technique called the dynamic harmonic domain method. These models are more accurate than existing models and aid the power systems engineer in designing improved control systems. The models were simulated in the presence of disturbances to show the evolution in time of the harmonic coefficients and power quality indices. The results of these simulations show the dynamic harmonic response of these FACTS controllers under transient conditions in much more detail than can be obtained from time-domain simulations, and they can also be used to analyze system performance under steady-state conditions. Some of the FACTS controllers\u27 models discussed in this work have a common DC link, but for proper operation, the DC side voltage must be held constant. The dynamic harmonic domain method was applied to the FACTS devices to design feedback controllers, which help in maintaining constant DC

Modeling The Metal Oxide Varistor Surge Arrester For Overhead Protection In Transmission Line

This project focused on the modelling and analysis of Metal Oxide Varistor Surge Arrester Model Type in Transmission Line for Overhead Protection. The primary cause of damage to electrical system equipment is transient overvoltage occurring in the power system. Therefore, the metal oxide surge arrester serves as a protective device to mitigate the impact of lightning and safeguard high and medium voltage system devices from switching overvoltage and lightning. The project utilized the metal oxide surge arrester to protect the transmission line insulations and equipment connected to the transmission tower. The simulation involved a lightning strike on the transmission tower, inducing a sudden high voltage in the system that could potentially damage other equipment. Moreover, this project simulated the dynamic properties of metal oxide varistor surge arresters using various proposed models, including the IEEE model, Pinceti model, and Fernandez model. These models were implemented in the PSCAD simulation software. A 1.5km single line of 275kV with 5 towers was modelled and simulated using the PSCAD software to conduct performance tests on different types of metal oxide varistor surge arrester models proposed for protecting the towers and transmission lines

Modelling 132 kV substation for surge arrester studies

Insulation coordination models are an essential part of power system studies and are used to determine the performance of a transmission line or substation. This paper generalizes the guidelines and parameters to be used in modelling the substation and in performing the analysis on the prediction of the transformer damage. Modelling parameters and the substation layout design are based and adapted from 132/11 kV Simpang Renggam – Ayer Hitam substation in Johor Baharu, Malaysia, courtesy of the Tenaga Nasional Berhad (TNB). The model is based on the single phase line model, as was suggested by the IEEE, to be adequate to represent the substation in transient analysis simulation. Extensive analyses on the placement of the surge arresters at the substation and a prediction of the transformer damage are also presented. The results obtained from this analysis are then compared with the suggested Basic Lightning Insulation Level (BIL) by the TNB, according to the standards, for assessing the percentage of transformer damage and optimizing the substation performance in terms of its reliability and cost effectiveness

Analysis of crosstalk and field coupling to lossy MTL's in a SPICE environment

This paper proposes a circuit model for lossy multiconductor transmission lines (MTLs) suitable for implementation in modern SPICE simulators, as well as in any simulator supporting differential operators. The model includes the effects of a uniform or nonuniform disturbing field illuminating the line and is especially devised for the transient simulation of electrically long wideband interconnects with frequency dependent per-unit-length parameters. The MTL is characterized by its transient matched scattering responses, which are computed including both dc and skin losses by means of a specific algorithm for the inversion of the Laplace transform. The line characteristics are then represented in terms of differential operators and ideal delays to improve the numerical efficiency and to simplify the coding of the model in existing simulators. The model can be successfully applied to many kinds of interconnects ranging from micrometric high-resistivity metallizations to low-loss PCBs and cables, and can be considered a practical extension of the widely appreciated lossless MTL SPICE model, which maintains the simplicity and efficienc

Transient simulation of lossy multiconductor interconnects

The transient simulation of electrically-long low-loss multiconductor interconnects is considered from a practical point of view. The importance of frequency dependent losses in these interconnects is discussed and a simple transmission line characterization procedure allowing for such losses is proposed. The characterization obtained yields simple and efficient interconnect models, that the user can include, without programming, in any simulator accepting differential operator

Modelling & Simulation of Power Oscillation Damping Controller

The main aim of this paper is to regulate power oscillation that is major concern associated with facility operation. During this analysis work is on SSSC-based power oscillation damping controller, which may damp the ability oscillations occurring because of the any modification within the line like unforeseen modification in load of line, prevalence of fault, transmission line switch and short circuit. During this work Simulation model of the 2 machine infinite bus system exploitation SSSC & power oscillation damping controller has been drained MATLAB/SIMULIINK and facility tool chest is employed for simulation purpose. These simulation models are setup into MATLAB primarily based power grid tool cabinet (PST) for his or her transient stability analysis. it's determined that with the correct modification of section of the injection of voltages through SSSC, electrical phenomenon & inductive compensation is provided by that enlarged and cut within the active power severally of line is done consistent with the mentioned power demand, however once solely the SSSC is employed within the line the subsiding time and amplitude of power oscillations area unit a lot of as compared once SSSC is employed with power oscillation damping controller. Once in 2 machine infinite bus systems 3-phase fault analysis is finished then it's determined that that the clearance time is a smaller amount once the system is supplied with SSSC and power oscillation damping controller along or togethe