Sharif Digital Repository

All over the world availability of electrical power is an important matter. Electrical power is a basic requirement in each country so with increasing the demand, supply system should be adjusted.Compressed Air Energy System (CAES) stores the excessive produced energy as compressed air and will inject it to gas turbine to produce energy in peak load hours.This project aim is modeling and analyzing of CAES considering reliability. In this project some of failure mechanisms have been identified and modeled and then the performance effect on system failure have been surveyed. This project innovation is incorporating operational models with reliability to determine the best performance for... 

Nowadays, with the development of the generation and storage technologies of electrical energy, increasing attention to environmental issues, and interest in improving the reliability of electrical energy distribution networks, the motivation to develop the distribution networks from pssive to active mode. Although, the utilizing of electrical energy storage systems (EESs) made technical and economic analysis of power system more complicated, but some of these challenges have faciliated by microgrids. Indeed, microgrids, as low voltage and medium voltage networks, can provide a set of significant benefits at the level of distribution networks by improving energy efficiency, power quality,... 

Non-Volatile Memories (NVMs) are emerging storage devices with promising characteristics such as low static power consumption, high performance, and non-volatile property to keep the stored data in the absence of power supply. Despite such interesting characteristics, NVMs suffer from high dynamic power consumption and limited lifetime. These limitations prevent NVMs from directly replacing the existing storage devices without any refinement in the architecture of computer systems. In this dissertation, we first investigate the characteristics of emerging NVMs and offer effective architectures to improve the efficiency of computer systems at the Operating System (OS) level. The main aim of... 

In order to reduce damage caused by power outages on rare events that lead to long-term disconnection of microgrid from utility grid, isolated mode performance of microgrids including wind and hudro turbines with energy storage systems is considered in this study. Using wind energy as a renewable resource is considered as an appropriate choice for power production in microgrids. However, the uncertainty in wind turbines power generation is something challenging. The existence of water resources near the wind farms causes a special opportunity for operation of these resources along with wind turbines. This thesis aimed at balancing energy supply and demand in island mode of microgrid,... 

Energy supplement for various demands, including industrial demands, has been human being's challenge over years therefore infrastructures have been developed to generate and transmit energy, gradually. These infrastructures are planned and operated mostly individually so they have less efficiency. Energy hub is a concept that considers energy supplement infrastructures and technologies together. Energy storages play a key role in energy hub. This research intends to provide a framework for industrial load supplement using energy hub concept emphasizing on energy storage role, developing energy supplement optimal size and operation methods. Regarding this method, after introducing main... 

LED Drivers with near 1 power factor, Because of using electrolytic capacitors (to become flicker-free) have lifetime drawbacks. This research will focus on solutions to use magnetic energy storage instead of electrolytic capacitors (used for energy storage) to solve lifetime drawbacks and decrease output light flicker. Calculations show that magnetic energy density using iron powder cores are lower than electrolytic capacitors, also a little lower than ceramic capacitors, but obviously higher than film capacitors. After calculations, conventional isolated and non-isolated LED drivers will be reviewed and new non-isolated off-line 230v with 10w output power LED driver with magnetic energy... 

Transmission expansion planning is an important part of power system planning that it task is to determine the optimal structure of transmission network based on load growth and to consider the future plan of system generation for a specified time period. The development of generation plans based on renewable resources, cost and time-consuming transmission expansion plans have caused that transmission planning to become a fundamental challenge. Therefore, in recent year’s decision makers of power systems are following the alternative ways of transmission expansion planning with lower cost and economic appropriate justification. Using of energy storage systems have cause to a delay on... 

Current trend of energy consumption and aging infrastructure of electricity grids mandates high amounts of investment in transmission and distribution networks. On the other hand, with increased awareness about environmental issues, share of renewable energy resources in power generation portfolio has risen in recent years. Microgrids, as one of the most promising solutions to tackle these issues, are able to accommodate high penetration levels of renewable energy sources and distributed generation in distribution systems. However, microgrids sizes are limited due to some operational considerations and as a result, efficient management of distribution systems with high penetration of... 

Many of today’s energy infrastructures need to be restructured to accompany the changes in the needs of humankind. On the one hand, more human activitie’s dependency on different energy carriers, and on the other hand, reduction of fossil fuels as the main energy resources, have caused that policies in many countries to be faced with fundamental changes in the area of energy. Optimal use of different types of energy carriers as an integrated system, is one of the main strategies that have been proposed to enhance energy efficiency. Using the concept of energy hub as the main key of integrated energy systems, this project intends to design a general framework for optimization and management... 

In the urban railway transportation system, large amount of power is consumed for starting the movement and acceleration. A great part of this energy is transformed to the train kinetic energy which in the case of break is reduced to zero. Thus recovering of train kinetic energy during the brake can help to reduce train energy consumption. One of the possible ways is using energy storage during the brake and using it again during acceleration. Storage can be performed in three kinds, fixed, mobile and hybrid. In this thesis, super capacitors have been investigated as fixed and mobile storages. After reviewing electrical railway transportation systems, elements of these systems have been... 

Renewable energy resources, e.g. wind, solar and geothermal, experience rapid progresses in electric power industry all over the world. So, it becomes essential that these free-emission electrical energy resources be integrated in the existing generating capacity planning procedures. On the other hand, the uncertain and intermittent nature of these energies has led to some problems in their integration in power systems. The reserve requirement in a renewable-based power system is a main challenge, which has to be addressed properly. In this way, this research presents an analytical approach, based on the modified PJM method, to quantify the risk of renewable energies commitment during the... 

Microgrids will be key components of future smart grids that integrate distributed generation energy with local loads and units for greater efficiency. However, the uncertainty and intermittent nature of renewable energy products prevent the reliable operation of the micro-grids. On the other hand, the introduction of electric vehicles into the transportation industry can be both a challenge and an opportunity for the power grid. Using electric vehicle batteries as an energy storage system is a new work in the smart grid environment. Using an electric vehicle battery as a storage system makes it possible to create a grid with a lower operating cost because of the development of renewable... 

Depletion of the fossil fuel resources along with the environmental concerns have led to a significant growth in utilization of Renewable Energy Resources (RERs). Among different kinds of RERs, wind energy due to maturity of its associated conversion technologies and also its widespread presence in different regions has experienced a more rapid usage in generation sector of power systems. Despite numerous benefits of this environmentally-friendly energy, uncontrollability and uncertainty in output power of wind turbines has resulted in many technical issues for operators of power systems. However, it has been shown that the presence of various storage system technologies can alleviate these... 

Electricity is one of the most important kinds of energy and also one of essential needs of humans for maintaining their life. Due to growth of costumer’s load and In order for delivering high reliable power to the consumers, the structure of the power grid must be expanded and/or demand side management policies like demand response programs must be taken into consideration. One of the most important and less-focused aspects of power grid expansion planning is, distribution system expansion planning. Distribution system expansion planning (DSEP) is an important task of electric distribution companies and operators in order to appropriately supply their customers load with the minimum cost... 

Buildings are responsible for 40% of total energy consumption worldwide. A significant portion of this energy contributes to building temperature control, and energy storage is an effective way to reduce energy consumption and to levelize the supply of heat load. A solution for reducing energy consumption in the building is to increase the thermal inertia of the building and to store energy using smart materials in the building components. Materials with phase change can stabilize the internal temperature of the building.In the present study, model is exmined with the help of modeling the thermal behavior of a room in Tehran in summer, using MATLAB software. The problem is solved by the... 

Energy storage is a pivotal technology to dealing with increasing demand for reliability and challenges of renewable energy integration. This thesis provides a benders decomposition framework for expansion studies of energy storage systems (ESSs) in high wind penetrated power system and uncertainties of wind farms expansion and wind speed. This work proposes probabilistic and robust approaches to determine the optimal location and size of storage devices to reduse wind curtailment. The proposed methodologies are implemented on the modified IEEE 73-bus test system and their anticipated applicability are compared to each other and well verified  

Proliferation of distributed energy resources and the developing of smart grid concepts are of a great importance. This, however, influences the future of power systems and necessitates more studies in order to cope with the changes. In this regard, uncontrollability issues are arised by introducing the renewable energy resources in the power systems. To address this issue, energy storage systems are used to mitigate negative consequences of using renewable energy resources. Accordingly, in this thesis, a new framework for determining the capacity and location of the energy storage systems is proposed. In addition, reconfiguration of distribution network is also concerned in order to... 

Dependency of human life to supplying of electricity energy, leads to different challenges for power system operators and planners. Demand growth and development of renewable energy sources have caused heavy investment costs to the transmission system. High price of construction of new transmission lines make planners to investigate effective factors on transmission expansion planning in order to make better decisions. On the other hand, the different amount of energy consumption during a day and the uncertainty of renewable energy result in transmission line congestion which cause electricity price gap between peak hours and off-peak hours. This price gap, also, necessitate the development... 

In recent decades, attention to renewable energy sources has been increased, and these resources will be an integral part of power systems in the future. Meeting the equilibrium point between power consumption and power generation at the power grid is of paramount importance. However, the equilibrium point is not solely dependent on the decisions of consumers and generation units and is influenced by other parameters as well. In this regard, penetration of renewable energies into the power system can affect this equilibrium point. These sources have random behavior, which will determine the future structure of the electricity grid. These sources can also change the shape of the network net... 

Energy storage systems are expected to play an important role in future renewable-based power systems. Recently, lithium-ion batteries have been attracting considerable attention as alternative energy storage systems due to their advantages. In this study, viability of battery storage systems as large-scale energy storage systems is studied in the context of a residential energy hub. A stochastic optimization problem is proposed for energy management of the energy hub where wind generation and demand are considered uncertain. In order to account for the degradation costs of the battery storage system, a data-driven State-of-health prediction model is developed based on the relevance vector...