dr. mohammad sadegh ghazizadeh

To improve the resiliency of the distribution system during normal and emergency conditions, approaches for planning and operating are required so that the network can supply more loads during normal and emergency times. Thus, with the cellular approach in network planning, according to the production and consumption, the cellularization of the network to supply more loads can be considered. Consequently, the identification of energy cells and the boundary of energy cells is a challenge in the planning issue. This article achieves and identifies the maximum number of energy cells and the border among energy cells of distribution systems. The proposed objective functions for solving the resilience problem include the number of supplied loads and the number of unsupplied loads in normal or abnormal conditions. Furthermore, the eigenvalues and eigenvectors of the Graph Laplacian matrix of the distribution network are used to identify the maximum number of cells in the distribution network and the boundary among the generated cells, considering the prediction of distributed generation and consumption load based on fuzzy modeling. To show the efficiency of the proposed method, the test systems of 69 and 118 buses have been simulated. The results prove the proper performance of the proposed method.

The fuel cells are electrochemical equipment that produces electricity by compounding hydrogen and oxygen in a specific membrane. Fuel cells, as a cutting-edge technology and a maintenance free energy conversion equipment, have the potential to play a significant role in generation of clean electricity, especially for home size CHP and clean transportation based on hydrogen fueled vehicles, can provide new opportunities in the world’s economy. In a study for the financial evaluation of the establishment of a fuel cell production facility in Iran, with a capacity of one million units per year, the economic modeling has been done by COMFAR software based on the UNIDO’s Instructions. According to the results of this evaluation, IRR was well beyond the discount rate and the normal payback period as well as the dynamic payback period were in the range of 4-5 years. All of the financial ratios and risk analysis in the six stages justified the bill of investing.

Developing countries like Iran face increasing energy demands due to population growth and economic expansion. The country has numerous renewable energy resources that account for the majority of its total energy supply. As fossil fuel resources are running out, the government plans to increase its renewable energy share. Many studies have already been conducted on renewable resources. However, the interdependence between the criteria used to evaluate renewable resources has not been considered. This paper presents a planning, decision-making, and policy framework for renewable energy based on the Analytical Network Process (ANP). ANP is a multi-criteria analysis method and provides a tool for determining the relative importance of all criteria that affect the decision objective. This process allows us to identify dependencies and include them in the multi-criteria evaluation and decision-making method from the point of view of a group of experts and professionals on the subject. The case study of this research is related to the country of Iran, and strategic criteria such as technology, economy, environmental, political and social impacts are calculated and priorities for renewable energy are set and analyzed. The results of this study show that solar energy is at the top of energy alternatives for the country. Such studies help countries to make the best use of their renewable energy sources

In this paper, to implement the reconfiguration of the intelligent distribution network and sizing the distributed generations (DGs), simultaneously, a stochastic multi-objective framework is presented in which the goals of reducing the energy losses, operating costs and emissions of environmental pollutants are followed. In most of the researches carried out for the network reconfiguration, the customer and distribution substation loads have been assumed to be fixed, while in reality these loads are changing. Generally, in the power system planning, the worst case which is the maximum possible load is considered, but the obtained configuration with this assumption is certainly not the optimal configuration. Therefore, in this paper, in order to cover the uncertainties associated with the load, the framework for the reconfiguration and DGs sizing problem is presented as a chance constrained programming problem and the Monte Carlo simulation is used in it. The problem of reconfiguration and DGs sizing at the same time in order to achieve predetermined goals is a multi-objective optimization problem. In order to solve it, this paper uses a newly introduced powerful optimization method called human-behavior based optimization approach. Finally, the proposed stochastic multi-objective framework is implemented on an IEEE 33-bus network, and the results are analyzed.

The issue of protecting the environment and preventing environmental pollution is one of the priorities of Iran’s economic and social development plans. The purpose of this paper is to analyze changes in the environmental effects of electricity generation, as electricity production patterns change, on production and welfare of households in Iran by using the social accounting matrix of 2011 and a computable general equilibrium model based on that framework. We evaluate four different policy scenarios based on the monetary value of the negative environmental effects of electricity generation.  The results indicate that application of electricity generation’s negative externalities has a positive effect on economic growth and a negative effect on household welfare. Secondly, with the current structure of electricity generation, the application of external costs of electricity production will increase economic growth by 0.0576 to 0.0736 percent and will reduce household’s welfare by -1.955 to -7.171 percent. Thirdly, by changing the pattern of electricity generation in Iran and moving towards clean electricity production and reducing electricity production from fossil fuels, the effect of electricity generation externalities on economic growth and welfare will be reduced. According to the research results, if the share of electricity production from fossil fuels is reduced to 85%, the economic growth and welfare of the household will respectively vary from 0.0553 to 0.0727 percent and from -1.733 to -6.363 percent.

Electricity is one of the most important infrastructure of the country. After the successful experience of industrialized countries for separate different parts and privatization in electricity industry, Iran since 1382 has begun to privatize the electricity industry. The electricity distribution sector is natural monopoly and, according to economic theory must operate under regulation for quantity of supply, price and quality to protect social welfare. There are various methods for regulation such as rate of return and incentive regulation, in many of these methods foucus on efficiency and productivity of firms. But the conventional static efficiency methods mainly reflecting short-run performance, and only show a close view of the long-run equilibrium path. When componis investment, the behavior of short-term factors that affecting the company may not be adjusted immediately, so short-run inefficiency will be transferred to subsequent periods. This effect caused by the the adjustment costs of capital and production capacity and in short run reduce efficiency in firms and should be considered in the regulation. In this paper, the dynamic efficiency of 39 electricity distribution companies during the period 2009-2015 was calculated using distance function. To estimate the the posterior distribution of model parameters, the simulation based on Markov chain Monte Carlo (MCMC) was used. The results show that environmental factors affect the efficiency in firms. The industry average efficiency increased from 67% to 70% and consistency for inefficiency was 92% during the period.

Utilization of power electronic interface in end-user appliances adds many newfound features to these devices. Cooperation in Volt Ampere Reactive (VAR) supply is one of these new capabilities and enables these devices to act as Distributed Energy Resources for reactive power injection and absorption. Proper integration of these power electronic interface capabilities into traditional utility system operations, it can be used as beneficial tools for distribution management and voltage profile enhancement. Regarding the present situation in distribution system, it is not practical to control all DERs centrally. Therefore, in this article, two proposed central control method and droop control were considered. The Multi-Criteria Decision Making (MCDM) technique with fuzzy theory was used to prioritize the candidate buses for their participation in Volt-VAR program. The contribution of the pre-mentioned active DERs in reactive power compensation was evaluated in this study

In this paper, a new control strategy is proposed for implementation in low-voltage microgrids with balanced/ unbalanced load circumstances. The proposed scheme contains, the power droop controllers, inner voltage and current loops, the virtual impedance loop, the voltage imbalance compensation. The proposed strategy balances the voltage of the single-phase critical loads by compensating the imbalanced voltage drop on the feeders. In addition, this strategy has also shown to be capable of restoring critical loads’ voltage to nominal values. This method also shares the real and reactive load accurately between DG units, based on their capacity. The simulation results in MATLAB /SIMULINK environment show the efficiency of the proposed approach in improving power sharing among DG units and decreasing voltage imbalance

Environmental problems are one of the most challenging issues for the entire world and each country. In economic studies, environmental issues are analyzed as negative externalities. In this article, the negative externalities of electricity production on the output growth of different sectors and household’s welfare in Iran’s economy have been studied through price system using Computable General Equilibrium (CGE) model empirically. In this regard, Iran’s Social Accounting Matrix of 2011 and GAMS software by introducing five scenarios related to environmental effects of electricity production have been used. The results show that firstly, the internalization of electricity production externalities reduces the output of agriculture and industry sectors in all scenarios, while the output of services will increase. Secondly, internalization of electricity production externalities increases total economy’s output and declines the household’s welfare.

The presence of new generation of electrical loads equipped with power factor correction devices makes it possible to utilize end-consumers in distribution grids voltage improvement. In this paper, reactive power and voltage control of a smart distribution grid by using end-consumers are studied. The distributed control algorithm is used as a suitable mechanism with less computational burden. In this regard, through the ε-decomposition approach the distribution network is divided into some subnetworks. After that, candidate buses for reactive power are selected and optimal reactive power injections at each candidate bus are acquired by genetic algorithm. Also, the impact of constant voltage distributed generations on voltage control is investigated. Finally, in order to evaluate effectiveness of proposed framework, IEEE 33-bus and 69-bus test systems are used. Simulation results show significant impact of proposed framework on voltage improvement of the distribution network.

Iran is flaring about 30 million cubic meters of associated gas per day in onshore oil fields. Suboptimality of economic extraction and production of exhaustible natural resources pawn the national benefits. Therefore, the main purpose of this paper is analyising the economic and technical feasibility aspects of reusing flared associated gas based on Capital Asset Pricing Model (CAPM). In this study time series data of average associated flared gas from 44 Iranian onshore oil fields has been employed. Additionally, three investment scenarios mean gas injection to the oil fields, electricity production and final consumption have been considered. Results of this study show that such oil fields produce less than 3 million cubic meters associated gas per day, gas injection to oil fields is the optimum alternative whereas using of associated gas to electricity generation is advised for other scenario.

Information about network components is of great importance for asset management decision making. This information is needed as input for the asset management decision process to come to a decision. To be able to extract the requested information، analysis and evaluation are needed. On the other hand، for efficient and economical asset management from reliability view point، analysis of failure rate for determination of origin of fault in component is an important task for asset manager. The failure rate of components is obtained by gathering data in outage management process that is available usually in detail in outage databases in electrical distribution. In this paper، failure analysis of process is obtained by assessment of process of component entry in distribution system. In this analysis، failure factors and sub-factors of each process is assigned by focus group and then relation between factors and causes of component failure is obtained by Delphi method. Finally، reasons of process-based failure are invested by modeling of failure rate for each process.

According to the latest developments in smart grid infrastructures of today’s modern networks, in this paper, end-consumers are presented as a means for participating in distribution networks voltage control. In this regard, for reactive power control of the smart grids, a distributed control approach is proposed as an efficient approach which improves computation burden of the problem, considerably. In the proposed approach, at first, epsilon-decomposition technique is adopted to calculate sensitivities of bus voltage to the injected reactive power. Therefore, buses with strong voltage relation are considered as a region which divides the network to some voltage related regions. Afterwards, candidate buses for reactive power injection are identified for each one of the achieved region. It is noted that, candidate buses of the network are those with reasonably better response to the reactive power injection. Finally, genetic algorithm is applied to obtain optimal reactive power injection of each region. For better evaluation of the proposed distributed reactive power control model, the IEEE 33-bus test system which is commonly used in literature is applied here. Simulation results clearly illustrate the effectiveness of proposed voltage control framework in improving voltage profile of distribution networks.

One of the most important ways that conserve fossil fuels is the use of renewable resources. Biogas is one of the most important renewable resources. Biogas is created from anaerobic fermentation of livestock waste in a fermentation chamber. Biogas technology is an important from several aspects; First، the significant social impact of this technology in the field of environment and human health. Second، it can be fired using biogas generators for generate electricity and third، sludge biogas unit output، would be a rich fertilizer that can greatly increase the efficiency of agricultural products. This paper delivers a cost-benefit analysis of biogas-fired plants، from the perspective of the private sector and the public sector، of the dairy industry in Iran. The results of both analyzes indicate high economic efficiency in the different sizes of biogas-fired power plants in Iran dairy industry.

Implementing a combined cooling, heating and power system(CCHP) to cool, heat and produce electricity is growing rapidly due to its efficiency and low emissions. In this paper, using economic analysis, the size and operation detail of the required gas engine and the specific electricity, cooling and heating load curves for a one year operating period has been determined. The proposed CCHP system meets thermal demands of the facility and has been evaluated under such strategy. Net Annual Profit (NAP) has been introduced as an objective function to be maximized through a developed nonlinear mixed integer programming software. The operation strategy and the payback period of the chosen system have also been determined. A study with the purpose of including or excluding subsidy prices has been carried out. Furthermore, a sensitivity analysis was elaborated in order to show the dependency of optimal solutions to some key contributing factors such as fuel price, electricity buying price and electricity selling price. Results show that, these parameters have significant effect on the system’s performance.

Due to growing demand of the electric energy، the need to transmission expansion planning is inevitable. In this paper at first the effective criteria in transmission Expansion Planning (TEP) are determined and a novel approach for TEP is proposed. In this approach Analytical Hierarchy Process (AHP) and entropy technique are utilized for TEP. The entropy is one of the techniques that uses for weight assessment in decision making in Multi Criteria Decision Making (MCDM) model. For this purpose، five criteria are introduced and then by utilization of the Entropy-AHP (EAHP)، the optimization of TEP problem is implemented. In the first stage، the Local Marginal Price (LMP) of each bus is calculated by Optimal Power Flow (OPF) execution. In the next stage، base on the criteria that will describe، the candidate lines are determined. Finally، the EAHP is used to assign a value to each criterion and by using these values the optimal line among the candidate lines is determined. The IEEE 14 bus network is used to simulate and evaluate the effectiveness of the proposed method..

Attention has been paid to the Demand Response (DR) programs in recent years to improve the power system operation. Demand Response affects market clearing price، which is the main motivation for investment، and thus the trend of investment on generation expansion will be affected. So far، the demand has been considered inelastic for modeling the investment on generation expansion. However، increasing the deployment of smart grid has waived this assumption. In this paper، we have used stochastic dynamic programming for modeling the generation expansion problem. We have considered both the renewable resources and demand response in modeling. In the proposed model، the uncertainty in generation and the accuracy of the price responsive demand performance are considered. In this regard، the market clearing price is determined by interaction between price and the price responsive demand. Some long-term indices are proposed and using the simulation results، they are evaluated. The achieved results، quantitatively confirm that the demand response results in decreasing the price and the outages and therefore improving the reliability.

This paper presents a decision making approach for mid-term scheduling of large industrial consumers based on the recently introduced class of Stochastic Dominance (SD)- constrained stochastic programming. In this study, the electricity price in the pool as well as the rate of availability (unavailability) of the generating unit (forced outage rate) is considered as uncertain parameters. The self-scheduling problem is formulated as a stochastic programming problem with SSD constraints by generating appropriate scenarios for pool price and self-generation unit's forced outage rate. Furthermore, while most approaches optimize the cost subject to an assumed demand profile, our method enforces the electricity consumption to follow an optimum profile for mid-term time scheduling, i.e. three months (12 weeks), so that the total production will remain constant.

Distributed generation has recently received a great deal of attention in Iran, as a result of which CHP systems have been employed more, due to their higher efficiency. This article, aims to optimize the system size considering the operating strategy of an industrial case study. Size and operating strategy for the steam boilers are optimized. The problem has been solved by using GAMS software to optimize the Net Present Value (NPV) of the plant from the plant owner’s point of view. A sensitivity analysis has also been performed to illustrate the optimal solutions variation caused by altering several key parameters such as fuel and electricity prices.

Voltage instability is a major threat for security of power systems. Preservingvoltage stability margin at a certain limit is a vital requirement for today’s power systems.Assessment of voltage stability margin is a challenging task demanding sophisticatedindices. In this paper, for the purpose of on line voltage stability assessment a new indexbased on the correlation characteristic of network voltage profile is proposed. Voltageprofile comprising all bus voltages contains the effect of network topoloy, load-generationpatterns and reactive power compensation on the system behavior and voltage stabilitymargin. Therefore, the proposed index is capable to clearly reveal the effect of all systemcharacteristics and events on the voltage stability margin. The most attractive feature forthis index is its fast and easy calculation from synchronously measured voltage profilewithout any need to system modeling and simulation and without any dependency onnetwork size. At any instant of system operation by merely measuring network voltageprofile and no further simulation calculation this index could be evaluated with respect to aspecific reference profile. The results show that the behavior of this index with respect tothe change in system security is independent of the selected reference profile. Thesimplicity and easy calculation make this index very suitable for on line application. Theproposed approach has been demonstrated on IEEE 39 bus test system with promisingresults showing its effectiveness and applicability.