Andreea El-Leathey

By Lucia-Andreea El-Leathey

Integration of distributed generation units and other users within the low and medium voltage distribution grid induces a variety of problems related to the management and control of microgrids. These aspects can be solved by using significantly different Energy Management Systems for the operation of microgrids, comparing to those applied to conventional power systems. The main objective of the Energy Management System is to ensure the rational use of energy, while minimizing its costs. The secondary objectives relate to increasing energy efficiency and reducing energy consumption, but especially to assuring the power facilities security. Moreover, the management of power systems to which renewable sources are connected is one of the main concerns of Distribution System Operators in order to ensure the safe operation, security of power supply, and the operation optimization from the economic side. The chapter regards the LabVIEW design and testing of an Energy Management System for the interconnected or islanded operation of a microgrid to the electric public grid. Furthermore, the chapter leads to the microgrids development in terms of operation and efficiency by achieving an Energy Management System designed for a small mixed microgrid with separate AC and DC rings bidirectionally interconnected by static converters.

Part of the book: Smart Microgrids

By Lucia-Andreea El-Leathey

A generic DC microgrid consists of a number of electric generators with static converters as interface modules, electric loads (to be connected either at DC or AC with inverter modules), as well as connection (by transformer and conversion modules) to the electric distribution network. The chapter envisages the state of the art on DC electric power distribution systems by tapping both high- and low-voltage direct current technologies and leading to the current development prospects. Moreover, a study on the existing standards applicable to DC distribution systems is achieved. The chapter leads to the establishment of the main technical requirements and characteristics suitable to the implementation of a residential DC microgrid. Also, electrical diagrams of the foreseen solutions and users’ recommendations and challenges are suggested by the paper.

Part of the book: Micro-grids

By Gabriela Circiumaru, Rares-Andrei Chihaia, Lucia-Andreea El-Leathey and Andreea Voina

The protection of fish habitat near water diversion or hydrotechnical facilities is of particular interest for researchers working in various fields. The chapter is focused on an experimental study of a fish behavioral barrier consisting of a bubble curtain operating along a river water intake scale model. It approaches elements of fish hydrodynamics, river water intakes, as well as physical and non-physical barriers for fish diversion from hydrotechnical facilities. The design, development, and testing of the fish behavioral barrier as well as the results of the experimental analysis are discussed. The proposed experimental setup was based on a barrier placed in the proximity of a river water intake scale model fitted and tested in a closed-circuit hydraulic stand. The intake chamber is provided with perforated orifices which communicate through an inlet with a lower tank for discharging the water into another tank located beneath. A certain water velocity within the hydraulic stand was set to assess the tandem operation of the bubble curtain and water intake. A sharp velocity gradient was found in most cases, indicating local velocity changes and creating the premises for impacting the fish behavior. Conclusions and future research development are also envisaged in the chapter.

Part of the book: Inland Waters - Ecology, Limnology and Environmental Protection [Working title]