Enhanced frequency regulation functionality of grid-connected PV system

Thesis (MEng (Electrical Engineering))--Cape Peninsula University of Technology, 2019Electric utilities are confronted with challenges like rising fuel costs, aging equipment, increasing energy demand, frequency regulation and the difficulty to integrate renewable energy resources into the grid. The presence of photovoltaic (PV) penetration on the utility grid is also increasing significantly in recent years. With the recent rise in PV penetration and the advancement of the global PV industry, there is an urgent and a necessary need to introduce features in PV systems that will make them respond smartly. However, much of these can be addressed without negatively affecting the total performance and power quality of the grid. Hence, engaging smart Grid technologies, and leveraging the benefits of the distributed nature of PV, new prospects to unearth value can be created. Through the implementation of progressive energy storage techniques, efficient two-way communications, a grid-tied PV system can create significant value, mostly through improved PV contribution in grid support functions like frequency regulation. An enhanced frequency regulation functioning scheme for a grid-connected photovoltaic (PV) system is modelled in MATLAB/Simulink software environment. The system is designed to operate in grid ancillary services precisely, frequency regulation function. The model consists of a Photovoltaic (PV) plant with a battery connected to the grid through a three-phase inverter. A bi-directional DC-DC converter between the grid and the battery system is included. The model has a battery storage system that provide steady and regular active/reactive powers available while the grid transmit specific amounts of power needed for a specific duration. According to the design, either the grid or the PV system depending on the dominant energy situation charges the battery. The battery is designed to discharge only when the grid demands energy from the PV and if the PV system fails to meet the demanded active power or reactive power. The PV system and the battery storage is integrated with the grid with the aid of dc-ac inverter in such a manner that bi-directional flow of active and reactive power is achieved. A 1 MW PV system is connected to the utility grid through a three-phase voltage source inverter system. The grid nominal frequency is set at 50 Hz under normal operation. However, the frequency decreased when the PV was not producing required power hence, the battery responded almost instantaneously and returned the frequency to the nominal frequency. The effectiveness of battery storage system for utility grid frequency regulation was substantiated from the simulation results attained

Proceedings of the Mobile Satellite Conference

A satellite-based mobile communications system provides voice and data communications to mobile users over a vast geographic area. The technical and service characteristics of mobile satellite systems (MSSs) are presented and form an in-depth view of the current MSS status at the system and subsystem levels. Major emphasis is placed on developments, current and future, in the following critical MSS technology areas: vehicle antennas, networking, modulation and coding, speech compression, channel characterization, space segment technology and MSS experiments. Also, the mobile satellite communications needs of government agencies are addressed, as is the MSS potential to fulfill them

Argonne National Laboratory Reports

This sixth symposium covers process control processes and issues involved in the conversion of fossil fuels into synthetic fuels

Navigation/traffic control satellite mission study. Volume 3 - Selected navigation/ traffic control satellite system analysis and equipment definition Final report

L band and VHF voice communication in satellite navigation and traffic control networ

Design/cost tradeoff studies. Appendix A. Supporting analyses and tradeoffs, book 2. Earth Observatory Satellite system definition study (EOS)

Attitude reference systems for use with the Earth Observatory Satellite (EOS) are described. The systems considered are fixed and gimbaled star trackers, star mappers, and digital sun sensors. Covariance analyses were performed to determine performance for the most promising candidate in low altitude and synchronous orbits. The performance of attitude estimators that employ gyroscopes which are periodically updated by a star sensor is established by a single axis covariance analysis. The other systems considered are: (1) the propulsion system design, (2) electric power and electrical integration, (3) thermal control, (4) ground data processing, and (5) the test plan and cost reduction aspects of observatory integration and test

Intelligent Circuits and Systems

ICICS-2020 is the third conference initiated by the School of Electronics and Electrical Engineering at Lovely Professional University that explored recent innovations of researchers working for the development of smart and green technologies in the fields of Energy, Electronics, Communications, Computers, and Control. ICICS provides innovators to identify new opportunities for the social and economic benefits of society.　 This conference bridges the gap between academics and R&D institutions, social visionaries, and experts from all strata of society to present their ongoing research activities and foster research relations between them. It provides opportunities for the exchange of new ideas, applications, and experiences in the field of smart technologies and finding global partners for future collaboration. The ICICS-2020 was conducted in two broad categories, Intelligent Circuits & Intelligent Systems and Emerging Technologies in Electrical Engineering

Cumulative index to NASA Tech Briefs, 1963-1967

Cumulative index to NASA survey on technology utilization of aerospace research outpu

Research and Technology Report. Goddard Space Flight Center

This issue of Goddard Space Flight Center's annual report highlights the importance of mission operations and data systems covering mission planning and operations; TDRSS, positioning systems, and orbit determination; ground system and networks, hardware and software; data processing and analysis; and World Wide Web use. The report also includes flight projects, space sciences, Earth system science, and engineering and materials

Contribution to the design of continuous -time Sigma - Delta Modulators based on time delay elements

The research carried out in this thesis is focused in the development of a new class of data converters for digital radio. There are two main architectures for communication receivers which perform a digital demodulation. One of them is based on analog demodulation to the base band and digitization of the I/Q components. Another option is to digitize the band pass signal at the output of the IF stage using a bandpass Sigma-Delta modulator. Bandpass Sigma- Delta modulators can be implemented with discrete-time circuits, using switched capacitors or continuous-time circuits. The main innovation introduced in this work is the use of passive transmission lines in the loop filter of a bandpass continuous-time Sigma-Delta modulator instead of the conventional solution with gm-C or LC resonators. As long as transmission lines are used as replacement of a LC resonator in RF technology, it seems compelling that transmission lines could improve bandpass continuous-time Sigma-Delta modulators. The analysis of a Sigma- Delta modulator using distributed resonators has led to a completely new family of Sigma- Delta modulators which possess properties inherited both from continuous-time and discretetime Sigma-Delta modulators. In this thesis we present the basic theory and the practical design trade-offs of this new family of Sigma-Delta modulators. Three demonstration chips have been implemented to validate the theoretical developments. The first two are a proof of concept of the application of transmission lines to build lowpass and bandpass modulators. The third chip summarizes all the contributions of the thesis. It consists of a transmission line Sigma-Delta modulator which combines subsampling techniques, a mismatch insensitive circuitry and a quadrature architecture to implement the IF to digital stage of a receiver