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Author: n.sene
Type: Publication
Date: 2015-04-01

VOLTAGE TRANSIENTS IN A DISTRIBUTION NETWORK CORRELATED WITH EVENTS IDENTIFIED BY A LIGHTNING LOCATION SYSTEM

Description:
Monitoring units for the measurement of high frequency voltage transients have been in operation at three different busses of an Italian medium voltage (MV) distribution feeder, mainly composed by ove... see morerhead lines, in March 2007 – August 2008. The feeder is located in a region characterized by a high ground flash density value (4 flashes/km2/yr); many of the recorded voltage transients may be correlated with the lightning events detected for the same region by the Lightning Location System (LLS) CESISIRF. The paper presents some experimental results obtained using the monitoring units and their comparison with computer results obtained using a LIOV-EMTP model of the considered MV feeder. A procedure aimed at achieving the best fit between measurements and calculations, which takes into account the uncertainties associated with LLS data, is also presented.

Authors:A. Borghetti, F. Napolitano, C.A. Nucci, M. Paolone, M. Bernardi, W. Schulz

X International Symposium on Lightning Protection, 9th-13th November, 2009 – Curitiba, Brazil

Tag(s): Lightning, distribution network, LIOV, EMTP

Author: ali.el-akoum
Type: Model
Downloaded: 381 times
Date: 2013-11-29

Blocks for frequency scan studies

Description:
Tow blocks for frequency domain studies :
* Impedance Z(s)
* Table (Frequency, magnitude and phase)

Tag(s): Frequency scan, impedance

Author: e.rutovic
Type: Library
Downloaded: 427 times
Date: 2013-02-26

Control Devices of TACS

Description:
An EMTP-RV TACS (Transient Analysis Control Systems Library) containing :
- TACS 50 : Frequency meter
- TACS 51 : Relay
- TACS 52 : Level-Switch
- TACS 53 : Delay
- TACS 54 :... see more Pulse delay
- TACS 55 : Digitizer
- TACS 56 : X-Y point list
- TACS 57 : Sequenced switch
- TACS 58: Integrator
- TACS 59 : Derivator
- TACS 60 : Input Selector
- TACS 61 : Input Selector
- TACS 62 : Sample and Track
- TACS 63 : Instantaneous Max/Min
- TACS 64 : Max tracking
- TACS 65 : Accumulator
- TACS 66 : RMS Meter

Tag(s): TACS

Author: AdminEMTP-RV
Type: Model
Downloaded: 396 times
Date: 2012-06-18

CB_arc_CM

Description:
This is an interesting case of the study of arc-circuit interaction in case of the interruption of a short-line fault.The arc is represented by a composite Cassie-Mayr model and the line is represente... see mored as frequency-dependant.
The case shows the application of black-box arc modeling in the study of kilometric-line fault capability of a 420 kV circuit-breaker. By zooming on the arc current and voltage near current-zero, post-arc current and initial TRV may be visualized in both cases of clearing and thermal failure.

Tag(s): Example, Protection

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