EMTP journal 

About: EMTP journal is an academic journal. The journal publishes majorly in the area(s): Emtp & Photovoltaic system. It has an ISSN identifier of 1881-9745. Over the lifetime, 22 publications have been published receiving 56 citations.

Transient transformer inrush currents due to closing time- and residual flux measurement-deviations if controlled switching is used (EEUG Meeting 2007: European EMTP-ATP Conference) -- (Applications in electrical machines and industry (1))

Abstract: During energisation of power transformers, transient inrush currents with peaks up to the short-circuit current may arise. Using controlled switching taking into account the residual flux, the transients can – in theory – be eliminated completely. Real factors such as closing time scatter and residual flux measurement uncertainty have to be considered when checking the suitability of controlled switching in the field. On account of this, a systematic transformer inrush current study depending on closing timeand residual flux measurement deviations for a 400 kVA dry-type distribution transformer will be presented in this paper. To carry out the systematic study for the energisation of the first phase, an interface between MATLAB and EMTP-ATP was implemented to share the strengths of both tools. Finally, recommendations for acceptable closing timeand residual flux measurement-deviations depending on the tolerable inrush current peak are given.

Modeling of nonlinear and hysteretic iron-core inductors in ATP (EEUG Meeting 2007: European EMTP-ATP Conference) -- (Applications in electrical machines and industry (2))

Abstract: A crucial element of transformer models for transient simulation is the representation of the core. The modeling of non-linear hysteretic inductor required to properly represent a transformer core is a challenge in ATP. The simulation of transient such as inrush and ferroresonance requires a correct handling of nonlinear and frequency dependent losses, accurate hysteresis loop representation, possibility of flux initialization, and a proper automatic initialization by disconnection transients. In addition to the investigation of standard non-linear inductor models of ATP, an advanced hysteretic model based on the Jiles-Atherton theory is implemented in MODELS and tested. The comparison of the models shows several weaknesses and the need of further investigations. A practical table summarizes the main quality and weaknesses of each model together with recommendations useful for the choice of the most appropriate model.

Out of step condition and torsional stress of synchronous generators (EEUG Meeting 2007: European EMTP-ATP Conference) -- (Applications in electrical machines and industry (1))

Abstract: Out-of-step operation of synchronous generators causes torsional and electromagnetic stresses. The aim of the paper is to compare three of the m ost used out-of-step protection algorithms, to find out some qualitative indications for protection setting and to evaluate the limits on these algorithms. Electrical and mechanical compone nts and protections have been modeled in ATP and subjected to several fault conditions . The study demonstrates that these algorithms should adapt the clearing time ac cording to the fault location. The next generation of algorithms should consider not only the impedance loci but also the torsional oscillations and their consequences on the generator voltage .

PQ-curve of wind power plants with ATP (EEUG Meeting 2007: European EMTP-ATP Conference) -- (Applications in generation)

Abstract: The use of renewable energies is steadily growing. Wind energy in Germany is the majority installed form of renewable energies. In Germany large wind parks are attached to high and very high voltage networks. Despite the high installed wind power, wind parks feed only active power into the network. The necessary reactive power for voltage control is produced up to now from the network and conventional power stations. Wind power plants are built in four types: with a synchronous generator, with a synchronous generator and full converter, with an induction generator and with doubly fed induction generator. ATP is used as a calculation program to exam, which of the four types can produce reactive power to support the voltage control.

Analysis of Ac Transmission from Desert-Area Large-Scale Photovoltaic Generation

Abstract: Large photovoltaic power generation facilities are expected to be installed in desert areas and provide electricity to rural areas through long cable transmission lines. However, ac transmission networks in such areas are usually inadequate for stable grid operation. One problem to be solved is voltage instability when large photovoltaic power generation facilities are connected to weak power grids. In this paper, two solutions for PV operation are proposed. One is use of the SVC and the other is that of the reactor. By conducting computer simulations on a test system, the proposed solutions are shown to improve ac voltage stability and to be feasible for the PV operation in desert areas. Keywords-component; Photovoltaic generation; SVC; Rector; Voltage stability;