مجله کیفیت و بهره وری صنعت برق ایران
سال پنجم شماره 2 (پیاپی 10، پاییز و زمستان 1395)

The increasing importance of energy resources in the formation and growth of economic processes as well as the need for utilization of these resources which are based on envirmental consideration and constant development of social and economical ones, to couseing identification subject and study of the factors on energy usage to be emboss. The size and structure of population is also among the factors that are important in issues related to the energy usage and it has been little studied. The electricity may be obtained to those energy which can be used to replace nearby. So this paper uses panel data of 12 provinces of the country, to analyze and compare the effect of the structure of population on the energy consumption of electricity in east (6 provinces) and west (6 provinces separately in a period, and the results show that income variant has a negative effect on electricity consumption in every provinces, however increasing of income in energy eastern provinces decreases the electricity consumption. The effects of variables such as population and urbanization has been positive in both provinces, but positive effects for the population of the eastern provinces on electricity consumption is more because of the high population of east. And the positive effect of urbanization is upper beacause of the existence of installations urban and residents consumption of electricity means.

Regarding the importance of energy storage in distribution networks and different battery technologies, in this paper the optimal battery planning is presented to compare different technologies without renewable energies in the grid. In long-term planning, the decision variables are the battery type, location, capacity and power rating which should be determined optimally. The objective function includes investment cost and O & M cost of battery as well as the grid operation and reliability cost. The technical constraints should be satisfied in project period as well. On the other hand, every technology has its own technical and economic parameters which change in different conditions. As a result, different parameters of the batteries as well as the behavior of the system are taken into account in a comprehensive study. The simulated annealing algorithm is used for optimization. This study show the Zn-Br and Na-S are the most suitable technologies. The results are generalized to different distribution networks using several sensitivity analyses. Finally, it is specified that employing the batteries is economical in those distribution grids which are connected to the global network and have not renewable distributed energy resources.

Loss of field (LOF) phenomenon in synchronous generators may cause serious damages and voltage drop in power system, which can be terminated to an unintended blackout. Conventional methods detect LOF on the basis of the measured impedance from viewpoint of the related terminals. Such methods not only are not fast enough, but also may exhibit mal-operation in the face of other phenomena, e.g. stable power swing (SPS).
In this paper, a novel algorithm is proposed to detect LOF in synchronous generators on the basis of some electrical parameters variations, including voltage (V), current (I), active power (P), reactive power (Q) and power angle (&delta). To evaluate the proposed method performance, some cases are simulated on a sample multi-machine power system under various operation conditions. Obtained results show that the proposed algorithm on the basis of V, Q and &delta not only can be considered as a fast LOF detector in comparison with the conventional impedance-based schemes, but also it can be introduced as a robust and secure technique in the face of SPS and other power system disturbances.

In the developing countries, there is an interest to attract investments in private and foreign sectors due to the lack of financial resource required for infrastructure projects. Build-Operate-Transfer (BOT) method is one of the approaches in which the private sector is assigned to construct the project and gains its own interest after which it transfers the project to the government. In this paper, according to the proposed case study, a method was obtained to determine the concession period length and the transfer point of project by taking into account both partie's willingness, effects of risks and uncertainty regarding the project's parameters, considering the lack of complete information at least for one party by using bargaining game theory and Monte-Carlo simulation.

In this paper, a non-isolated three-port zero voltage switching bidirectional dc-dc converter without input current ripple. Some advantages of proposed converter are zero voltage switching of main switches, zero current switching of auxiliary switches. By using two active snubbers, it is possible to reduce circulating current and conduction losses. Free ripple condition of input currents is obtained by using coupled inductors in any stages that it reduces size of converter. The proposed converter can be used in boost, buck and buck-boost operation mods. If all of low voltage sources are equal or less than high voltage source, it is possible to increase the number of input sources to AWT IMAGEas a kind of AWT IMAGE-port converter. Finally, the zero voltage and zero current switching of switches and ripple free input currents of the proposed dc-dc converter is verified thruogh the simulation results in PSCAD/EMTDC software.

The present study tries to investigate the relationship between emotional intelligence and job satisfaction among Electricity Distribution Company employees of Tehran city. The design of the study is of retrospective descriptive correlational type. In order to collect the data for the three intended variables, the researcher used the Bar-On 90-item Emotional Intelligence Inventory, Eysenck’s 57-item Personality Questionnaire and Herzberg’s36-item Job Satisfaction questionnaire. 274 participants were chosen based on cluster sampling. The result of the study shows that coefficient of determination of job satisfaction through emotional intelligence and personality characteristics in a sample of male employees is (R2=0/58), and among females employees it is (R2=0/44) and generally among all employees it equals (R2=0/49). The results of beta coefficient revealed that emotional intelligence has more predictive power than personality characteristics in predicting male and female employees’ job satisfaction.

There are many advantages to utilize storages in electric power system. Peak shaving, load leveling, load frequency control, integration of renewable, energy trading and spinning reserve are the most important of them. Batteries, especially redox flow batteries, are one of the appropriate storages for utilization in distribution network. This paper presents a novel, heuristic and practical method for optimal scheduling in distribution network with flow battery storage. This innovative method to enhance the efficiency posts that are needed to install storage is very convenient. Peak shaving and load leveling is considered as the main objective in this paper. Several indices are presented in this paper for determine the place of storages and also scheduling for optimal use of energy in them. Simulations of this paper are based on real information of distribution network substation that located in Semnan, Iran.

Participation of load in operation of power system is essential for operators and the economy is the first option for this purpose. This participation nominated as demand response programs (DRPs). DRPs result in reducing reliability cost and electricity price, congestion relief and reduction in environmental impacts. What is important is the proposing a comprehensive DRPs model for accurate planning. Different model of DRPs is proposed that is nominated as static and dynamic models in this paper. Dynamic models used from demand elasticity to price that is different for each customer. This issue brings inaccuracy in model and poor planning.
In this paper a comprehensive model of DRPs based on price elasticity to total demand is proposed that is same for all customers. So, inaccuracy in model and poor data base challenge will be removed. Numerical results show the effectiveness of the proposed model.

The increasing of electricity consumption and future demand is one of the major issues of power companies around the world, and smart grid is one of the best solutions to the outage of this problem. Smart grid aims to solve problems existing power grids and better and more efficient power system management is raised. This paper presents a novel long term energy management approach based on genetic algorithm and PSO algorithm, suitable for implementation in the smart grid context. The main purpose of this paper is to present a method for determining effective investing in the domestic appliance optimization, aim to reducing energy consumption in the household sector. The first step toward achieving these goals is the providing a model for appliance efficiency rate. This model is used for investment optimization in a variety of appliances and its effect on household power consumption. In the second step, a cooperative game with transferable utility is used for modeling the coalition of special items which customer is willing to more invest in them, such as basic appliances. The purpose of this step is to increase the possibility of the presence of these appliances in the consumption management program. Finally to solve the problem has proposed a hybrid tool based on PSO algorithm and genetic algorithm. The simulation results represent 45.56% of electricity consumption reduction and 80.48% of repairs cost reduction. The outcomes prove that the proposed hybrid algorithm is an efficient and effective tool to solve the long-term household electricity consumption management problem.

Several research evaluated the efficiency of electricity distribution companies by custom Data Envelopment Analysis (DEA) method, but recent researches have shown that by only reliance to the custom or optimistic DEA, we can’t certainly rank the companies according to their efficiencies, so they use pessimistic efficiency concept and integrate these two efficiencies in a mathematical function format to rank companies with high certainty and without needing to intricate calculations. In this research we want to calculate the relative efficiency by Double Frontier DEA that is more precise than the custom method. The results show that Mashhad’s electricity distribution company among the 39 studied companies has the first grade, while by using custom DEA method, ten other companies stand on the efficiency frontier.