Sharif Digital Repository

The term “Smart Grid” generally refers to a power grid equipped with the advanced technologies dedicated for purposes such as reliability improvement, ease of control and management, integrating of distributed energy resources and electricity market operations. Improving the reliability of electric power delivered to the end users is one of the main targets of employing smart grid technologies. The smart grid investments targeted for reliability improvement can be directed toward the generation, transmission or distribution system level. However, radial operating status, aging infrastructures, poor design and operation practices and high exposure to environmental conditions have caused the... 

The restructured power system and smart grid requires an advanced communication infrastructure. Application of such communication infrastructure brings numerous privileges to power generation industry, on the other hand introduces challenges to this industry, namely cyber attacks. Recently, cyber attack in electric markets aiming economic interests have been attractive to many electric industry researchers and planners. In electric market cyber attack, by means of influence in data transmission equipment like SCADA, the attacker manipulates the transferring data. This manipulation is conducted in a targeted behavior so as to make the network operator get wrong estimation of actual LMPs in... 

Increasing demand in power systems necessitates the Generation Expansion Planning (GEP) which is to determine the type, size, and location of new generating units in a planning horizon. The final solution of GEP is based on the minimum cost and/or optimum reliability taking into account various constraints such as capacity of units and lines, operating constraints, and budget restrictions. This paper presents a model based on scenarios for generation expansion planning and units retirement decision. The proposed model could be used by vertically integrated utilities as well as the ISOs in electricity markets to obtain generation expansion schemes. In this approach, uncertainty of units are... 

Nowadays, considering the dependence of the life quality to the electric energy, exhaustion of the existing facilities in the distribution networks, and restructuring of the electric industry, the reliability improvement turns out to be one of the most important considerations in order to reducing the operational cost. Furthermore, the expansion of existing networks, substitution, and refinement of the exhausted facilities for improving the reliability can lead to remarkable expenses. Considering the limitations of budgets of distribution network companies, these plans cannot be put into practice. Therefore, operators and planners of this industry have to find ways to operate the existing... 

Residential demand response is an appropriate control tool for improving system reliability. This project intends to establish a model to activate residential demand response to improve distribution network reliability. Two centralized and decentralized models are proposed. The models aim at minimizing the damage cost imposed by load curtailments following unexpected events. In the models, it is supposed that distribution system operator (DSO) and responsive customers already signed a contract authorizing the DSO alters the operation of responsive appliances whenever system reliability is jeopardized. In centralized framework, Responsive customers deliver the technical data of their... 

As a matter of fact, power systems are always faced with a variety of uncertainties. These uncertainties change system parameters in an unwanted manner which may deteriorate the system security and reliability. For instance, a transmission line which is designed for a certain capacity may be suffered as a result of load increment and consequently may influence the normal operation of other network elements. In recent years, as a result of environmental considerations and especially after the oil shock at 1973 which caused the the energy prices to increase unprecedentedly, the human has taken more attention to renewable energies exploitation. Theses energies have a fluctuating nature and are... 

Plug-in hybrid electric vehicles (PHEVs) present environmental and energy security advantages versus conventional gasoline vehicles. In the near future, the number of PHEVs will likely grow significantly in the world. In spite of the aforementioned advantages, the connection of PHEVs to the power grid may create a series of new challenges for electric utilities. If PHEV penetration exceeds a certain amount it can endanger power system security. In this research, a new charging control scheme which includes both the customer and grid acquiescence is presented. Optimal charging algorithm is developed which minimizes the electrical charging payment of customers. The optimization problem in this... 

The current state of restructuring in the electric power industry has forced power companies to maintain and enhance service reliability and quality while controlling associated costs. Therefore these companies often seek to improve operational performance, increase productivity and promote management of their assets to restrain production costs while satisfying customers’ needs. Maintenance of system components has great impacts on both service quality and also system costs. However, it has been proved that traditional maintenance strategies which have been implemented in electrical companies are inefficient. Thus, Managing maintenance procedures would help companies to reduce their costs... 

Considerable attention has been given in recent years to renewable energy sources due to concerns about dwindling fuel reserves and the potential impact of conventional energy systems on the environment. Wind power is one form of renewable energy resources and also considered as Dispersed Generation (DG). Widespread utilization of wind power imposes many effects on planning and operation of power system. In other side, reliability evaluation and enhancement is an important factor in modern power system planning and operation. So, reliability assessment of wind turbines is of great importance and will receive more attention in the future according to increase of WT utilization. The... 

This thesis represents a comprehensive view of electric vehicles from the macroeconomic policy in the energy sector perspective. In fact, in this thesis all the efficient factors in the presence of electric vehicles in the transport sector have been completely proceed. Environmental, economic, social and political factors, power grids and infrastructure are considered as the impressive factors. In order to check all factors comprehensively, Systems thinking based on dynamic system method is used. The causal relationships between all the variables which are involved in the presence of electric vehicles and related models to this thesis are simulated in VENSIM software. To investigate this... 

Smart grid brings miscellaneous concepts and advantages; increasing power quality, decreasing outages, motivating the consumers to participate in power system plans, and accommodating distributed generations (DG) are the most important purposes of smart grid implementation. Appearance of modern technologies makes operators devise better operation function. The effect of these technologies on the power system should be probed by sufficient criterions. In addition, preventing undesirable consequences of new technologies operation in the grid is the requirement of having smarter grid. In this thesis, based on the smart home concept two issues are discussed. In the first issue, a new algorithm... 

Toward the cost-effective solutions for the challenging features of maintenance in nowadays restructured power systems, reliability centered maintenance (RCM) has been introduced as the efficient key due to its streamlined performance. RCM, although has proven its noticeable merits in many industries, has not been yet furnished with efficient analytical methods in the power engineering context. In a power distribution system, vividly in a deregulated market and restructured environment, blind time based maintenance of all the distribution equipments is neither affordable nor economically justifiable. Moreover, an acceptable level of system reliability is an indispensable criterion for the... 

Power distribution systems have been traditionally operated as passive networks which consume electric power supplied by the transmission grid. Increasing utilization of wind energy in distribution systems, notably wind energy, is changing the way distribution sys-tems are operated. The distribution system operators (DSO) would operate the available wind power for reducing the power purchased from the wholesale market. However, high penetration of wind energy in distribution systems would require advanced operation mod-els and additional flexibility in system to offset the variability and uncertainty associated with wind energy. In addition, wind availability often does not positively... 

Implementation of telecommunication-based distribution automation is possible in both centralized and decentralized manners. Although centralized automation is more pervasive than decentralized automation, benefits of decentralized automation systems, like improving reliability and speeding up the fault management process, encourage distribution companies to implement these systems. However, high cost of decentralized automation can be a deterrent to most distribution companies. Therefore, economic planning and creating economic justifications for decentralized distribution automation are necessary for the development of these systems. In this dissertation, economic analysis and planning of... 

Available Transmission Capability (ATC) is a measure of remaining capability in the transmission system for future use which is calculated and posted by Independent System Operator (ISO) considering various certain and uncertain power system parameters. ATC can be affected considerably by application of flexible AC transmission system (FACTS) controller among them Unified Power Flow Controller (UPFC) is the most recent one applied in power systems. This thesis is aimed to study the probabilistic ATC assessment incorporating UPFC. It first proposes a probabilistic ATC calculation method which is capable of considering various certain and uncertain parameters of ATC calculation in the... 

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... 

Smart consumers have a major role in the development of the smart grid. On the other hand, increasing need for more flexibility in DGs highlights the consumer’s role. This is possible with the development of smart appliance and appropriate communications infrastructure to active consumers. Today, with the development of smart grids, it is possible to control different parts of home energy systems and manage energy consumption. In this project a comprehensive model has been developed to optimize energy consumption in smart home. In the next phase of the thesis, due to the random nature of solar energy and electric vehicles, stochastic model of smart home energy system is discussed. At this... 

Considerable developments in demand-side real-time telemetry systems allow ISOs to use demand-side provided reserves in ancillary service markets. Presently, many ISOs designed programs to utilize the reserve provided by demand response resources in their market, and deploy them in emergency conditions. These programs are called ancillary service demand response (ASDR) programs. This thesis presents a stochastic programming model to schedule reserve provided by demand response resources in load buses of system. The demand-side reserve resources are modeled by demand response providers (DRP) which have the responsibility of aggregating and managing responses of customers. The reserve provided... 

In recent years, the pace of increment in electrical energy consumption is getting faster. Establishing new power-plants to keep a balance between generation and consumption not only has a high investment cost but also is a time consuming procedure. Thus, several studies have focused on the demand side management. Residential consumers possess remarkable portion of total electricity consumption. Accordingly, at first, the appropriate residential demand response program is selected based on presented experimental criteria. In the next step, since the network reliability is an important issue to the operators, the impact of implementation of the demand response program is studied on the...