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Author: AdminEMTP-RV
Type: Document
Downloaded: 534 times
Date: 2012-06-18

A Tool for Steady-State and Dynamic Analysis of PV Generation in Low Voltage Grids

Description:
Authors:
Dennetière S., Mahseredjian J., Duvauchelle C., Tounsi B.
This paper describes a tool based on EMTP-RV that simulates the steady-state and the dynamic behavior of photovoltaic (PV)... see more units on a low voltage grid. The tool takes into account load and irradiance curves to evaluate the impact of PV units on the voltage profile along the grid as well as the dynamic behavior of PV inverters. This tool has already been used to analyze and explain undesired disconnections of PV units in an existing system.

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Author: AdminEMTP-RV
Type: Document
Downloaded: 478 times
Date: 2012-06-18

Presentation of an approach based on EMTP for the calculation of lightning induced overvoltages

Description:
Authors:
A. Xémard, P. Baraton, B. Bressac, N. Qako, J. Mahseredjian, G. Simard, J. Ribeiro, R. Tarafi, A. Zeddam.

Abstract:
LIPS (Lightning Impact on Power Systems) is a toolbo... see morex based on EMTP (DCG version) and devoted to the calculation of the failure rate of apparatus due to lightning. This software covers direct and induced lightning. It has been developed in a partnership project between France Telecom, Hydro-Québec and électricité de France. The induced lightning nearby the electrical system. It is based on the following computational steps:
1) For each overhead line and underground cable of the electrical system, two equivalent current sources are calculated in the frequency domain, representing the illumination of the conductors by external electrical field due to lightning. These sources are evaluated in the frequency domain, taking into account the variation of the parameters of lines and cables with frequency. The conductivity of the ground is taken as finite. The modal theory is applied in the case of multi-conductor cable or line.
2) The equivalent sources are converted into time-domain and then included in an EMTP representation of the system allowing a time-domain transient computation. this approach and follow by comparisons between induced overvoltages calculated by LIPS and results from the literature.

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Author: AdminEMTP-RV
Type: Model
Downloaded: 197 times
Date: 2012-06-18

TCR1

Description:
Example of single phase Thyristor Controlled reactor using TACS control devices. This circuit reproduces the TCR case presented in the EMTP Workbook volume 4 chapter 6.

Example of single ph... see morease Thyristor Controlled reactor using TACS control devices. This circuit reproduces the TCR case presented in the EMTP Workbook volume 4 chapter 6.

The basic static Var system consists of a static switch in series with an inductor. This is normally called a phase controlled reactor, or Thyristor Controlled Reactor (TCR). The TCR is in parallel with a fixed capacitor. Together they interface with the power system at some interconnection point. The control circuit of the TCR can be divided into three parts. There is the gate pulse generator (GPG), the heart of the control system, a voltage regulator and an interface to the power systems which could be simply a RMS voltage meter.

The purpose of the gate pulse generator is to provide firing pulses to the thyristors. The regulator calculates the conduction angle, ?, which is passed to the gate pulse generator as a control signal. It is the function of the gate pulse generator to generate the correct firing pulses to achieve the requested conduction angle, ?. In this example the gate pulse generator is modeled using TACS control devices.

Tag(s): Power Electronics