Sharif Digital Repository

With the rapid proliferation of residential rooftop photovoltaic (PV) systems, current and voltage unbalance issues have become a matter of great concern in low voltage (LV) distribution feeders. This, however, necessitates identification of the hosting phase of the connected single-phase customers and PV panels. Both of the challenges have been addressed in this thesis. In the first place, this thesis proposes a mixed integer linear programming (MILP) model for phase identification problem. The model considers potential error in the input data provided by smart meters. To mitigate negative impacts of the error, the data associated with several consecutive time intervals are taken into... 

Water is crucial to human being. We use water for a wide variety of uses daily. However, leakage has caused substantial water loss to our precious processed water. The major contributor to non-revenue water in Iran is pipeline leakages. The water industry in the nation has invested in equipment to detect and localize leaks in water distribution systems. One of the equipment mentioned is acoustic-based. The principle of acoustic is that whenever a leak is present in a pipeline, noise is generated and will travel along the pipeline. The acoustic leak detection method is then derived by calculating the distance traveled by this noise generated by the leak. Different equipment based on acoustic... 

The usage of plugin hybrid electric vehicles has environmental benefits. However, the penetration of these components raises important concerns for grid planning. Thus, it is necessary to model the load change due to their charge to investigate the impact of these vehicles on distribution networks. For this reason, it is necessary to determine the specifications of these vehicles, such as battery charge and energy consumption on daily trips. In addition, the study of some behavioral patterns of these vehicles and some experts are necessary to complete the model.In this thesis, an active distribution network is planned using dynamic programming formulation. In this model, some buses are added... 

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 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,... 

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... 

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... 

Renewable resources, because of their compatibility with the environment, accessibility, and low cost of operation, have become the center of unprecedented attention. Since the output of these resources cannot be predicted accurately, they are usually implemented in microgrids with conventional generating units and energy storage systems.Furthermore, distribution networks are integral parts of power systems, and many studies have been conducted in order to improve them. Because of high investment and operation costs of distribution networks and environmental concerns, it is necessary to conduct meticulous economic studies so that with proper investments, profitable opportunities are provided... 

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... 

Remote-controlled switches (RCSs) have the ability to quickly isolate the faulted area from other parts of distribution systems. On the other hand, the distributed generation resources (DGs) and tie lines can supply the interrupted loads after fault occurrence as a microgrid. In this regard, this thesis proposes a planning model for simultaneous placement of RCSs, DGs, and tie lines in distribution systems with complex topologies to improve their reliability and resiliency. Presence of renewable DGs (RDGs) including photovoltaic cells (PVs) and wind turbines (WTs), as well as the uncertainties of loads, RDGs, and outage duration of the faulted areas are also considered in the proposed... 

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... 

Nowadays, moving toward new technologies and smart grids is a successful way to prevail over distribution system challenges. In the presence of smart grids, demand-side management (DSM) is capable to affect the expansion of network resources. An effective DSM tool is demand response (DR). In this thesis, distribution system planning (DSP) considering DR is presented and the effects of DR on DSP are investigated. This thesis proposes direct load control (DLC) DR which is an incentive-based program (IBP) where a utility offers financial incentives to the customers to control their consumption through installing smart meters and switches. The utility deploys the DR program to reduce network... 

Planning of distribution networks is usually accomplished using a cost-based conventional model that minimizes the total cost of construction and reinforcement of substations and feeders. The resulted expansion plan designed by this cost-based model is not necessarily the best choice for an electrical distribution company in the nowadays deregulated structure. This happening is mainly due to the fact that the utility seeks to maximize its profit in this competitive environment. On the other hand, this model does not consider the upcoming new challenges ahead of distribution systems, such as smart grid and automation. This thesis presents a novel profit-based model for multi-stage... 

The purpose of this study is to investigate the resilience of the urban water supply network against earthquakes, A hydraulic analysis of the water supply network was implemented in Rtx software to study the effective parameters in the resilience of the network. Rtx software is a tool for assessing the reliability and resilience of communities and infrastructure to natural hazards by taking into account related uncertainties. The water supply network, like other networks, is affected by earthquakes. The seismic damage varies depending on the vulnerability of the network, the intensity of the earthquake, the focal depth, and the distance from the epicenter. Thus, it reduces the ability of the... 

Recent widespread blackouts around the world have highlighted the fact that power grids must not only ensure reliability against high-probability, low-impact events (HPLI), but also against low-probability, high-impact events (HILP) such as earthquakes, hurricanes, and hurricanes and resist against unnatural events such as cyber attacks. On the other hand, transformation of traditional electricity distribution systems into smart networks that have the ability to automatically perform switching and fault locating can enable utilities to minimize operational costs in case of HILP events occurences. Although the use of distribution automation has been suggested as one of the smart grid... 

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,... 

Making distribution networks smart includes all appropriate hardware and software devices for controlling and making operation of the network optimized. (SCADA system, distribution management, communication equipments, substation automation, monitoring equipments, etc). Monitoring and management of electricity distribution networks enable us to control and record events in the operation. Equipments in the distribution substations, will be under full time monitoring and hence, we would be able to protect them against over loads, over voltages, load unbalances and inefficient usage of transformers capacity and other distribution instruments. It also enables us to manage operation switchings,... 

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... 

This dissertation proposes a new platform and a new software for evaluation of urban Water Distribution Network (WDN) resilience. Resilience is considerd as the ability of an infrastructure to come back to steady state after being affected by any environmental or man-made disturbance. WDN, as an essential infrastructure, has major role on resilience and sustainability of cities and communities. Today, uninterrupted performance of WDN is a basic need of people who live in cities. This uninterrupted performance becomes bolder in face of man-made or natural disasters like earthquake. The uninterrupted performance of a system is dependent on the system’s resilience. Majority of researchers... 

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...