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Author: Jesus MR
Type: Example
Downloaded: time
Date: 2025-09-29

PI to CP conversion

Description:
Example to estimate the parameters of a CP model from a Pi section (sequence data).

Tag(s): Lines, CP model, Pi, conversion

Author: h.gras
Type: Publication
Date: 2021-11-30

Modular Multilevel Matrix Converter for Low-Frequency AC Transmission – modeling and Simulation in EMTP

Description:
Authors: Rafael Castillo-Sierra and Giri Venkataramanan
The transmission of power with AC faces limitations both to the stable operation of the electrical system and to the physical properties of... see more the transmission lines. Therefore, alternatives are being sought to mitigate these problems without the need to build new lines or replace existing ones with new, more powerful ones. In this context, a proven method makes it possible to overcome these problems by reducing the frequency at which power is transmitted. This method is known as Low Frequency AC Transmission (LFAC). In this sense, the model presented in this Research Contribution Prize Program EMTP® 2021 shows the implementation of a low-frequency transmission line in a small power system. The model presented shows a new block in EMTP of the AC/AC converter used, the Modular Multilevel Matrix Converter (MMMC) and the controls necessary for its operation. Time domain studies show that the technology is feasible and has the potential to improve the controllability and stability of transmission systems.

Tag(s): AC-AC power conversion, Electromagnetic Transient Studies in EMTP, Low frequency AC transmission, Modular Multilevel Matrix Converter

Author: thpapad
Type: Document
Downloaded: 147 times
Date: 2017-11-03

MIMO-OFDM Narrowband-PLC in Distribution Systems: Impact of Power Transformers on Achievable Data Rates

Description:
Power-line communication (PLC) is gaining a renewed interest, due to the smart grid (SG) emerging communication requirements. Among other communication technologies, PLC is a very efficient and feasib... see morele solution, especially for the extended SG distribution networks. However, it is very challenging to consider both the medium- and low-voltage parts of the distribution network as a whole communication medium, due to the attenuating effects of distribution transformers, limiting PLC applicability. In this paper, data transmission through distribution transformers is investigated by means of multiple-input multiple-output (MIMO) narrowband power-line communication (NB-PLC) system, utilizing orthogonal frequency-division multiplexing (OFDM) technology. Multi-conductor distribution line and measurement-based transformer models are developed to characterize the MV-LV PLC channel. In addition, OFDM signal processing techniques are applied to enhance the achievable data rates. The transmit power budget and bit allocation across the OFDM sub-channels of the spatial beams are optimized to maximize the data rate through the distribution transformer. The achievable data rates are calculated and systematically analysed for different scenarios to investigate the effects of the distribution lines, connected loads, noise models, etc. Results reveal the superiority of the proposed MIMO design against the traditional SISO systems. In addition, the possibility for an extensive and reliable application of MV-LV PLC communications through distribution transformers is shown.

Tag(s): Distribution lines, distribution transformers, MIMO-OFDM, power-line communication, smart grids

Author: thpapad
Type: Document
Downloaded: 387 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: h.gras
Type: Example
Downloaded: 734 times
Date: 2015-06-16

Content of the webinar studies from A to Z on TRV

Description:
Designs built or presented during the webinar of the series Studies from A to Z on Transient Recovery Voltage
Models built:
- Rating TRV envelop (IEC 62271-100 / C37.010 - 2011)
- CP / ... see moreFD lines
- Thevenin equivalent of a network

Tag(s): TRV, Transient recovery voltage, short-line fault, terminal fault, substation, 62271, 37.011, lines, switching, thevenin