Sharif Digital Repository

Nowadays, large-scale power outages induced by ever-growing natural disasters are increasing at a galloping rate. In this regard, this paper aims at improving the resilience of power distribution systems in facing high impact low probability (HILP) events in the planning phase of the system. To this end, optimal switch placement along with the optimal distribution line hardening strategies is proposed to mitigate the repercussions of the natural calamities. So, decreasing the failure probability of the distribution lines alongside the optimal placement of remote-controlled switches (RCSs) to increase the maneuvering capability of the system, the system operator would be able to strengthen... 

Electric distribution system is one of the most important parts of power systems owing to delivering electricity to consumers. The major amount of losses in a power system is in distribution level. Optimal distributed generation (DG) placement and sizing have a significant effect on power loss reduction in distribution systems. In this paper, a mixed integer conic programming (MICP) approach is presented to solve the problem of DG placement, sizing, and hourly generation with the aim of reducing power loss and costs in radial distribution systems. The costs include both investment and operational costs of DGs. Hourly load variations are considered in the model. To verify the effectiveness of... 

Nowadays, with the increasing use of renewable energies in low voltage (LV) feeders, phase balancing research areas are of great importance. However, the lack of information about the hosting phase of customers and renewable sources is the missing link in such researches. To address this barrier, this paper proposes a mixed integer linear programming (MILP) method to identify the hosting phase of customers as well as renewable energies, such as photovoltaic (PV) panels. The model considers potential error in the input data. To overcome the complexity caused by data error, the input data in several time intervals are taken into account by the model. The model solves the phase identification... 

Distribution network reconfiguration as a technique for reducing network losses and enhancing voltage profile has attracted attention of many researchers. In spite of impacts network reconfiguration can have on power quality indices, the potentials have not been studied enough. To fill the gap, this paper presents a method to determine optimum network configuration considering voltage profile, network losses, and total harmonic distortion (THD). The proposed method also vouches for radial structure of the network, supplying all loads, and maintaining voltages and currents within allowable bounds. Since network reconfiguration problem is a combinatorial optimization problem, a meta-heuristic... 

Distribution networks are designed in loop structure, while they are operated as radial networks. In this regard, the location of normally open (NO) switches is usually determined by either minimizing real power losses or maximizing the reliability level. However, considering both losses and reliability in the decision making procedure may lead to a better solution. To do so, this paper proposes a mathematical model to find the optimal configuration of NO switches such that losses and reliability are optimized. The multi-objective model is scrutinized via weighted sum approach to achieve a single-objective model. The model is formulated in mixed integer quadratically constrained programming... 

This chapter presents the optimal switch deployment in distribution systems. First, an explanation regarding different types of switches and their functionality is introduced. Then, a fundamental description of fault management procedure in distribution networks is presented. Thereafter, the mathematical formulation of optimal fault management process is described. Optimal switch deployment problem is formulated in the format of mixed integer programming (MIP). The impact of remote controlled switch (RCS) and manual switch (MS) is scrutinized on the interruption cost once they are installed either individually or simultaneously. The concept of switch malfunctions is explained and the... 

Sectionalizing switches are the main components of any restoration scheme in fault situations of power distribution systems. In this paper, customer outage costs reduction is aimed through the optimal simultaneous placement of manual and remote-controlled switches (RCSs). Network reconfigurations are constrained such that operational considerations like statutory ranges for voltage levels, lines' thermal capacities, and necessity of radial configuration be conserved. Total cost reduction is mathematically modeled in a mixed-integer linear programming (MILP) model that makes the global optimal solution accessible. The validity of the proposed model is evaluated on the IEEE 33-bus network. In... 

Remote-controlled switch (RCS) placement problem is used to optimally deploy the switches in distribution networks to enhance system reliability. The candidate locations of RCSs are usually assumed at the main feeder while the possible locations on the laterals are ignored. This study studies the impact of considering laterals as potential switch locations and demonstrates that deploying RCSs in laterals would change the optimal number and location of the switches. To do so, this study proposes a mathematical model for the switch deployment problem by taking into account the laterals. The proposed model is formulated in mixed integer linear programming format which can be solved via... 

This letter proposes an analytic framework for achieving an optimal solution for phasor measurement unit (PMU) placement problem. The proposed technique is on the basis of the cost/benefit analysis while long-term economic aspects and existing technical issues are simultaneously accounted for. More deployment of PMU devices would result in more reliable and secure electricity services. The reduction of system risk cost is hence recognized as the benefit associated with the development of wide-area measurement system (WAMS). The optimal number and location of PMUs are determined such that adding more PMUs is no longer beneficial. Two systems are examined to demonstrate the performance of the... 

This letter proposes an analytic framework for achieving an optimal solution for phasor measurement unit (PMU) placement problem. The proposed technique is on the basis of the cost/benefit analysis while long-term economic aspects and existing technical issues are simultaneously accounted for. More deployment of PMU devices would result in more reliable and secure electricity services. The reduction of system risk cost is hence recognized as the benefit associated with the development of wide-area measurement system (WAMS). The optimal number and location of PMUs are determined such that adding more PMUs is no longer beneficial. Two systems are examined to demonstrate the performance of the... 

One of the most important issues in the smart grid is to quantitatively assess the impacts of distributed energy resources (DER) on the distribution system reliability. Solar cells (SCs) as developing DERs are normally placed close to the load centers. In this paper, a new algorithm is developed to evaluate distribution system reliability, considering SCs in the vicinity of the end-users. The probabilistic nature of the demand and SC power output are investigated to solve challenges of integrating these intermittent resources with the distribution system. In a smart home, to handle the variation of SC generation, solar load controller (SLC) is utilized to match load and generation of SCs... 

Sectionalizing switches (SSs) are often presumed to function fully reliable. However, SSs are exposed to have some malfunctions, whereby undermining their ability to improve service reliability. This study presents a model to integrate SS malfunction probability into SS placement problem. The model aims to minimize the total SSs costs as well as customers interruption cost. The proposed model is formulated in mixed integer programing (MIP), which can be easily solved via several available solvers and gain global optimal solution. The proposed model indicates the extent to which the placement problem is affected by uncertainty associated with SSs functionality, and how not considering SSs... 

Fault indicator (FI) plays a crucial rule in enhancing service reliability in distribution systems. This device brings substantial benefits for fault management procedure by speeding up fault location procedure. This paper intends to develop a new optimization model to optimally deploy FI in distribution systems. The proposed model aims to consider a tradeoff between the total customer interruption cost and FI relevant costs, including capital investment, installation, and maintenance costs. As the main contribution of this paper, the problem is formulated in mixed integer programing, which guarantees global optimum solution achieved in an effective runtime. Moreover, the model takes... 

Automation systems provide substantial improvement in service reliability through speeding up fault management procedure. However, this is at expense of high investments whose justification needs thorough cost/worth analyses. This paper introduces a mathematical model to optimally place automation system devices within distribution networks. The model establishes a trade-off between service reliability improvements and the relevant costs. Among different automation system devices, fault indicators and remote controlled switches are considered here. Also, the impact of manual switches is regarded since their number and location significantly affect the solution of the placement problem. The... 

Sectionalizing switches (SSs) are often presumed to function fully reliable. However, SSs are exposed to have some malfunctions, whereby undermining their ability to improve service reliability. This paper presents a model to integrate SS malfunction probability into SS placement problem. The model aims to minimize the total SSs costs as well as customers interruption cost. The proposed model is formulated in mixed integer programing, which can be easily solved via several available solvers and gain global optimal solution. The proposed model indicates the extent to which the placement problem is affected by uncertainty associated with SSs functionality, and how not considering SSs... 

Sectionalizing switches play a crucial role in enhancing service reliability to the end users of distribution networks. However, they might encounter failures, thereby causing interruptions in the networks. The existing switch placement models consider only the pros of switches in improving service reliability, while they fail to deem switches cons in possible failures and thus increasing system interruptions. This letter intends to show the importance of switch failure in the switch placement problem and the extent to which switch failure alters the switches allocation in a network. To do so, we develop a novel model based on mixed integer programming format to integrate the impacts of... 

Sectionalizing switches play a crucial role in enhancing service reliability to the end users of distribution networks. However, they might encounter failures, thereby causing interruptions in the networks. The existing switch placement models consider only the pros of switches in improving service reliability, while they fail to deem switches cons in possible failures and thus increasing system interruptions. This study intends to show the importance of switch failure in the switch placement problem and the extent to which switch failure alters the switches allocation in a network. To do so, we develop a novel model based on mixed integer programming format to integrate the impacts of... 

Automation systems provide substantial improvement in service reliability through speeding up fault management procedure. However, this is at expense of high investments whose justification needs thorough cost/worth analyses. This paper introduces a mathematical model to optimally place automation system devices within distribution networks. The model establishes a trade-off between service reliability improvements and the relevant costs. Among different automation system devices, fault indicators and remote controlled switches are considered here. Also, the impact of manual switches is regarded since their number and location significantly affect the solution of the placement problem. The... 

Sectionalizing switches (SSs) are often presumed to function fully reliable. However, SSs are exposed to have some malfunctions, whereby undermining their ability to improve service reliability. This paper presents a model to integrate SS malfunction probability into SS placement problem. The model aims to minimize the total SSs costs as well as customers interruption cost. The proposed model is formulated in mixed integer programing, which can be easily solved via several available solvers and gain global optimal solution. The proposed model indicates the extent to which the placement problem is affected by uncertainty associated with SSs functionality, and how not considering SSs... 

Sectionalizing switches play a crucial role in enhancing service reliability to the end users of distribution networks. However, they might encounter failures, thereby causing interruptions in the networks. The existing switch placement models consider only the pros of switches in improving service reliability, while they fail to deem switches cons in possible failures and thus increasing system interruptions. This letter intends to show the importance of switch failure in the switch placement problem and the extent to which switch failure alters the switches allocation in a network. To do so, we develop a novel model based on mixed integer programming format to integrate the impacts of...