12 Results for the search "DC":
Author: thpapad
Type: Document
Downloaded: 339 times
Date: 2017-11-03
INDUCED VOLTAGES AND CURRENTS: OVERVIEW AND EVALUATION OF SIMULATION MODELS AND METHODOLOGIES
Description:
In this paper induced voltages and currents caused by underground cables are calculated in cable sheaths and nearby metallic pipelines. The performance of several simulation methods and models are inv... see moreestigated in steady-state, considering also different implementations in ATP-EMTP, EMTP-RV and PSCAD/EMTDC. The analysis is extended in the simulation of transient overvoltages in cable systems, evaluating the accuracy of two widely used simulation models. The influence of different parameters is investigated, among them specifically the earth properties. Results reveal that implementing accurate earth representations, earth conduction effects have a significant impact on induced voltages at the power frequency, while for high frequency phenomena the influence is minor.
Tag(s): induced voltages
Author: e.rutovic
Type: Example
Downloaded: 608 times
Date: 2014-06-09
CIGRE DC Grid
Description:
EMTP-RV DC Grid test cases developed in the scope of the CIGRE B4-57 group.
Author: gerinlajoie.luc
Type: Model
Downloaded: 425 times
Date: 2012-11-23
Extra control of machines - IEEE AVR
Description:
The proposed AVR sub-circuit models consist of a few IEEE 421 standard exciter[1] and Power Systems Stabilizer and governor. Don't forget to click the require observed signals in the SM devi... see morece, see Observe and Mechanical Tabs (vd, vq, if, Pmss, Efss, Omega_1, etc.) In this file, many duos and trios combinations of:
Exciter:
- IEEEX1 (dc1),
- IEEEX2,
- IEEEX4,
- IEEET5,
- EXST1,
- EXST1A,
Stabilizer:
- PSS1A,
- PSS2B,
- PSS4B,
- Q type II (var control)
Governor:
- IEEEG0,
- IEEEG1,
- IEEEG3,
- DEGOV1
- GAST,
- TGOV1,
- TGOV5[1]
IEEE Std 421.5, Recommended Practice for Excitation System Models For Power System Stability Studies, 2005
Tag(s): Components
Author: AdminEMTP-RV
Type: Document
Downloaded: 249 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.
Author: AdminEMTP-RV
Type:
Downloaded: 219 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.