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Author: AdminEMTP-RV
Type: Document
Downloaded: 251 times
Date: 2012-06-18

On the implementation of a hysteretic reactor model in EMTP

Description:
Authors:
Sébastien Dennetière, Jean Mahseredjian, Manuel Martinez, Michel Rioual, Alain Xémard, Patrick Bastard

Abstract:
This paper presents the implementation of a hysteretic... see more reactor model in a transient analysis package. Themodel is available in a currently developed EMTP (DCGEPRI) version. It is demonstrated how the hysteretic reactor equations can be solved to eliminate topological limitations and allow solving large scale networks efficiently. Numerical robustness aspects and the representation of minor loops are emphasized. The model demonstrates new and not previously available computational capabilities.

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Author: AdminEMTP-RV
Type:
Downloaded: 220 times
Date: 2012-06-18

PM_subcircuit

Description:
Example of a user defined model. In this case a line-start permanent magnet synchronous machine is connected to a simple power network. This machine, working as a generator, has been modeled by contro... see morel elements. This user defined model is not recomme.

The line-start permanent magnet motor is a high-efficiency synchronous motor with self starting capability when operating from a fixed frequency voltage source. The permanent magnets embedded in its rotor provide the synchronous excitation and the rotor cage provides the induction motor torque for starting. The difference in permeability between the magnet and rotor core also results in significant magnetic saliency and reluctance torque at synchronous speed. At asynchronous speeds, the dc excitation and saliency of the permanent magnets will cause pulsating torque components. When the field strength of the magnet is too strong, a line-start permanent magnet motor may fail to synchronize because of the excessive pulsating torque component from the dc-excitation of the magnet.

The objective of this case is to create a user defined model of a permanent magnet synchronous machine. With this model the user can explore the behaviour of the torque components during a starting run of the generator from standstill. In particular, we will examine the ability of the motor to synchronize with various values of magnet field strength, mechanical loading and rotor inertia.

This case also shows the capabilities of EMTP-RV to create user defined models. This model assembled with control elements is particularly clear. I needed 4 hours to create this model and to validate it with an existing Simulink model ! The user can see the whole model with its equations on one page (see Figure below)

This model is given as an example of user defined model and should not be used for other purposes.

Tag(s): Example, Motor

Author: AdminEMTP-RV
Type: Document
Downloaded: 466 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: 356 times
Date: 2012-06-18

Reactor

Description:
This is an advanced case of a three-phase shunt-rector modeling along with a Cassie-Mayr Modified circuit-breaker arc model.

This design introduces the way three-phase shunt-reactor may be ... see moresimulated in EMTP-RV. Moreover, it introduces an advanced circuit-breaker arc model known as Cassie-Mayr Modified or Advonin arc model.

Tag(s): Example

Author: AdminEMTP-RV
Type: Model
Downloaded: 193 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