César Angeles-Camacho

Methodologies Used in the Extrapolation of Wind Speed Data at Different Heights and Its Impact in the Wind Energy Resource Assessment in a Region

For many centuries to date, wind energy has been used as a source of power for a whole host of purposes. In early days it was used for sailing, irrigation, grain grinding, etc. At the onset of the 20th century, wind energy was put to work on a different use: power generation and electricity-generating wind turbines were produced. Wind turbines do convert the wind renewable energy into electricity, thus becoming a clean and sustainable power generation alternative. There is a large number and wide assortment of wind turbines which, over time, have evolved in its two key areas: capacity and efficiency. The evolution of wind turbines has been boosted thanks to the growing awareness on environmental issues which in turn stems from an equally growing concern over conventional fossil fuel energy sources. Furthermore, high oil prices and other financial incentives are also bearing their respective weights on the issue. Large scale wind turbines in the range 4 to 10 MW are now being developed and used for equipping large-scale wind farms worldwide. The power developed with wind generators depends on several factors with the noteworthy ones being the height above the ground level, the humidity rating and the geographic features of the area but the chief factor is the wind speed. Therefore, the first step in ascertaining the energy that can be produced and the effects of a wind farm on the overall electricity network calls for a thorough understanding of wind itself. There are different methods used in estimating the wind potential. This paper is aimed at presenting the impact of various methods and models used for extrapolating wind speed measurements and generate a relevant wind speed profile. The results are compared against the real life wind speed readings. Wind resource maps come as a plus factor.

Three-phase STATCOM Models for Large-scale Newton-Raphson Power Flow Studies

This paper presents two models of the Static Synchronous Compensator (STATCOM) both models suitable for three-phase power flow studies using the Newton-Raphson in both frame-of-references: polar and rectangular co-ordinates. In both cases, the STATCOM is taken to be a voltage source converter (VSC) and its associated shunt-connected transformer. The ensuing equivalent model allows for a direct voltage regulation and/or for injection of active power at the DC side of the converter. Also these models do not compromise the quadratic convergence characteristics of the Newton- Raphson methods.

Dynamic phase-domain modelling and simulation of STATCOM in large-scale power systems

This paper presents a dynamic model of the Static Synchronous Compensator (STATCOM) in the phase frame reference and rectangular coordinates. The STATCOM is taken to be a Voltage Source Converter (VSC) coupled with a shunt connected transformer to the power system, the equivalent model allows for a direct voltage regulation and its incorporation into an algorithm for the analysis of their contribution to the stability of the SEPs to dynamic phenomena. The tool used for the study is called Dynamic Power Flow. Validation with long-term test large-scale power systems are presented and discussed, which proves to be suitable for this type of dynamic analysis.

A Dynamic State Estimator Based Control for Power System Damping

Interarea power oscillation damping enhancement in large interconnected power systems is often accomplished using supplementary controls at the synchronous machines involved and with the use of flexible ac transmission system devices. The power system literature has demonstrated that wide area signals could be more effective than the local signals for these controllers. In some cases where phasor measurement units are used, all the required control signals may not be available. To alleviate these cases, control signals are obtained using estimated signals from a “dynamic state estimator,” and a robust supplementary controller is deployed. In this paper, the cited strategy is illustrated using a static var compensator. The feasibility of the proposed method has been demonstrated on the IEEE 50-generator test system.

Design and implementation of a real-time monitoring tool for power engineering education

This article reports on the implementation of a real‐time monitoring system in a laboratory test grid based on synchrophasorial measurement units. The system consists of the installation of different types of units for monitoring the electrical parameters of the network. The information is transmitted to a power data concentrator equipment, through a local area network under TCP/IP protocol. All the information received is properly processed and systematically stored for future use. A graphical application was developed to visualize the information in real‐ time or to perform off‐line power analyses. The functionality of the monitoring system was verified on several test grids and is used for teaching and research for both undergraduate and postgraduate students in the power electronics laboratory at the Engineering Institute of the Universidad Nacional Autónoma de México.

STATCOM on the Mexican Power Systems: Two Case Studies

Mexico, as other countries, has set targets for using renewable energy generation; however, because of its variability, it may affect the electricity system operation and lead to electrical breakdown. STATCOM is a power electronic device used to mitigate those risks. To analyze the STATCOM behavior for integrating wind generation into the Mexican Electrical System, without compromising its integrity, two cases were studied. In the first case a region of the Northeast of Mexico is analyzed, where there are two power plants with a total of 990, and 1,600 MW more will be added soon for wind generation. Under these circumstances, an electrical failure close to generator stations is risky for the system stability. For this reason, the behavior of the network was analyzed by incorporating a STATCOM to maintain the voltage values close to nominal, after introducing a three-phase fault at a bus bar near generation. In the second case, the Southeast region of Mexico is considered, where there are three parallel transmission lines of 243 km each. Capacitive reactance is presented because of the lines length, and it raises the voltage in bus bars during low demand. To avoid such overvoltage, currently one of the lines is disconnected. A STATCOM is proposed for absorbing reactive power to maintain the nominal voltage without disconnecting the transmission line during low demand.

Proposed STATCOM application on the Mexican Electrical System

In order to analyze the static synchronous compensator behavior, in this work two cases in the Mexican Electrical System are used. The first case is located in the northeast, which considers the use of a static synchronous compensator to achieve electrical stability after an electrical failure. The coupling transformer between the static synchronous compensator and the network is studied with different impedance values. The second case is presented in the southeast region, where the static synchronous compensator is used to maintain the voltage profile during periods of low chargeability.

Redes de transmisión inteligente. Beneficios y riesgos

Actualmente los sistemas electricos operan cada vez mas cercanos a sus limites de estabilidad, es por ello que se hace necesaria y primordial la transicion hacia nuevos sistemas de transmision que garanticen la eficiente entrega de la energia electrica, evitando con ello cortes de energia que generan importantes perdidas en la economia de cualquier pais del mundo. En este documento se realiza un analisis de los elementos necesarios para una sana y eficiente transicion de una red de transmision electrica verticalmente, integrada hacia una red de transmision inteligente . Se presenta un analisis comparativo entre dos de los marcos de referencia mas importantes, el de la UE y el de EUA, en el modelo, desarrollo, beneficios y riesgos en la implementacion de estos sistemas.