Sharif Digital Repository

Power distribution network planning and related optimization is an interesting research subject and many papers have been published on this topic. Distribution network planning started in developed countries. Therefore network models are based on reliable network data, educated crew and low interest rate. Nowadays, Iranian engineers and researches try to use their research result for solving network optimization problems but sometimes the result of optimization is not achievable in reality. In current thesis, modeling approaches developed by previous researchers were compared and the effect of model simplification was evaluated. This evaluation was based on data gathered from local power... 

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... 

A significant part of the power system energy losses occurs in the distribution transformers. The high loss share of these transformers in yearly electric energy losses of the country’s power network contributes to about 8% of the 20% total national electric energy losses. On the other hand due to the high rate of yearly increase in electric energy usage in the country, optimal distribution transformer planning and sizing pays an important role in reduction of these losses in the coming years. To address these concerns, the distribution companies should optimize the utilization of electric energy sources which results in an increase in their profits. This thesis introduces a new detailed... 

In this dissertation, the value of distribution network reconfiguration in presence of distributed generation is investigated. In the first step, a mathematical optimization model is devised to minimize daily network losses via applying hourly reconfigurations. The results show that the hourly reconfiguration reduces the losses. Then, sensitivity analyses on the renewable penetration, wind and load correlation, switching cost and wind power prediction are conducted and discussed. The switching cost analysis revealed that a great amount of loss reduction could be attained with a small number of switching operations. The worthiness of reconfiguration becomes more in systems with high... 

The price that customers pay for electric energy is determined by cost of generation, transmission and distribution parts. In Practice all customer have main concern about reliability of electric energy, because of it’s major effect on different aspect of life. Although customers are interested to have fully reliable service, but power companies are aware that it is impossible to achieve this goal from technical and economical aspect. The utilities and customer benefits can be achieved through minimization of the total investment cost of network, while improving the reliability and quality of electric service. This also requires to minimize the customers service interruption time. To meet... 

The regulation is necessary for the electric distribution networks as a natural monopoly. Regulators have been applied the Performance Based Regulation (PBR) for the control of price. The common model of PBR is price cap. Price cap creates sufficient incentive for cost efficiency. However, it decreases the service quality in distribution systems. The aim of this thesis is to design a comprehensive model for improvement of service reliability in the presence of PBR. An incentive model is developed using reward-penalty theory and yardstick theory. Reward-penalty theory is a financial approach that rewards the utility with good reliability and penalizes the utility with poor reliability. The... 

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... 

In recent years, climate change due to greenhouse gases caused an increase in frequency and intensity of the natural disasters such as hurricanes, blizzards and floods. Moreover, it is anticipated that such events will increase in the future. As a result, power system decision makers are looking for methods to improve power system resiliency against such natural disasters with low occurrence probability and high impact. In this report, the distribution system resiliency has improved via placing remote control sectionalizing switches and micro grids formation during natural disasters. In this regard, the concept of resiliency and its characteristics along with the effect of remote control... 

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,... 

Virtual power plant (VPP) aggregates the capacity of many diverse distributed energy resources (DERs); it creates a single operating profile from a composite of the parameters characterizing each DER and can incorporate the impact of the network on aggregated DER output. In modern power systems, technical virtual power plants (TVPPs) play an important role enabling presence of DERs in electricity markets. This thesis addresses the optimal bidding strategy problem of a TVPP that participates in the day-ahead (DA) electricity market. TVPP schedules its energy resources in a manner that maximize its profit in DA market. Hence, the optimal schedule of its resources is achieved. In a proposed... 

Based on codification and implementation of regulations of supporting from development of distributed generation sources, it is expected that in future years, investment in distributed generation scheme will be welcomed by private investors impressively. Under this circumstances, distribution Company will be faced with new chances for improving quality level of their services and optimal management of penalty-reward schemes. Penalty-reward schemes is set by legislator for distribution Company in order to improve their network. One of the pioneer ways is using distributed generators. So first, distribution Companies have to find optimum places for using these generators and in the second step... 

Reward-penalty schemes are known as the most effective tools to regulate the service quality. This thesis tries to design a comprehensive reward-penalty scheme to properly motivate electricity distribution companies (DisCos) to improve the reliability and reduce the energy losses in their networks using Distributed Generation (DG) Resources. So, as the first step, the designing methods of reward-penalty scheme (RPS) and their advantage and disadvantages are introduced, and also a method based on concept of the Yaredestic theory is proposed. The proposed method uses the Fuzzy clustering and is able to set the parameters of RPS in a fair and efficient way. The proposed RPS is implemented on... 

Due to the increasing influence of distribution generation , their effect in planning can't be ignord , especially solar panels ,which are incresing rapidly. The main purpose of this thesis is to an active distribution network that annually load bus and the amount of photovoltaic production in it increases and plan dynamically. In the planning that is done , uncertanty in the amount comsumption load and uncertanty in the pattern of sunlight and also annual innterest rates in the classical system we have planned by optimizing the network expansion costs , in addition to supplying the load bus, we can keep the voltage drop bus and line filling within the allowable . To do this , we considered... 

The worldwide increase in greenhouse gases is one of the most important human concerns today, and reducing emissions is on the agenda of politicians and the international community. Globally, the transportation fleet is one of the major sources of environmental pollutants due to the use of fossil fuels, and replacing this fleet with electric vehicles will play an important role in reducing the emission of environmental pollutants. These environmental concerns and the advancement of technologies used in electric vehicles in recent years have led to a relative increase in the presence of electric vehicles in the transportation network. The acceptance of these cars, on the one hand,... 

The purpose of the current study is developing an evaluation model for the electrical grid. Resilience is an approach toward risk management against disorders and protecting the system during critical conditions. The importance of resilience assessment, especially in crucial infrastructures, has always been at the center of attention. Nonetheless, previous studies in this field were mostly limited to micro-scales, meaning that only a limited part of the system was evaluated. Therefore, such studies rely on technical data and system details. This issue renders macro-scale assessments challenging. Some of the models, which are based on analytical-statistical methods, examine the systems at... 

The number and severity of natural disasters have significantly increased in the recent years. Extreme weather-driven events cause catastrophic damages to power grid components. As a consequence, severe power outages occur in the affected grids. According to the published reports on natural disasters, 90 percent of such outages originate from distribution systems. In addition, the repair process of the damaged elements takes a long duration. Thus, it is necessary to improve the distribution system (DS) resilience against natural disasters. The strategies for resilience enhancement can be classified into two main groups: hardening and operation-oriented measures.Formation of microgrids has... 

A high percentage of power grid faults occur in the distribution sector, which causes customers to experience power outages. In order to maintain a good reputation with customers and maximize their satisfaction, improving the reliability of the services provided in the electricity distribution network and minimizing related costs have always been one of the most important challenges for electricity network managers. Therefore, managers and legislators of the power network are always looking for a way to maintain the reliability level of the power distribution network and also to improve it. So far, many researchers have focused on setting goals with the help of average performance methods... 

Power networks are evolving dynamically, and a wide variety of control and visibility devices are being integrated into the power system, generating a significant amount of data. This thesis focuses on analyzing subscribers' electricity consumption patterns, which explores the potential insights embedded within these data. The information assessed includes active and reactive energy consumption, the current imbalance index, and the power factor. Over 6 billion records were obtained from the Hormozgan Electricity Distribution Company for the foundational dataset for this study. An extensive section of this thesis is dedicated to removing empty values and outliers from data. After this, a...