نشریه تحقیقات نوین در سیستم های قدرت هوشمند
سال پنجم شماره 2 (پیاپی 12، پاییز و زمستان 1395)

Nowadays, the use of new energies as scattered sources of production has increased dramatically throughout the world. This paper aims to study the technical and economic parameters of a diesel, wind, photovoltaic, biomass and battery system for a large indirect electricity user In eastern Iran. As a case study, the feasibility of implementing a hybrid system to meet the needs of the population of the residential community with a load factor of 0.25 was investigated. The design is intended to reduce system costs over its 20-year life span. Homer software design in order to Modeling the system's performance and identifying its optimal areas is based on technical, economic, and environmental analysis. At the end, the proposed model, along with the anomaly, radiation, fuel prices and cost of biomass related to the eastern parts of Iran, has been simulated with the help of Homer software. Finally, by comparing the results obtained, it can be concluded that with the proper design of resources Dispersal production can reduce a significant amount of costs and make economic use of renewable energy.

Circuit Breakers (CBs) of transmission and Super distribution are considered to be the most important equipments of power systems. CBs should operate safely to protect power systems against faults and perform tasks such as trip and connect load. The purpose of this paper is to present reliability block diagram of transmission and Super distribution CBs and evaluation level of reliability of transmission and Super distribution substations of Khorasan Regional Electric Company (KREC). To achieve this goal, a four-step approach has been proposed. In the first step, collecting information about the failures and events occurred in the KREC has been investigated. Failures and events lead to an emergency exit and outage of CBS are studied and categorized. In the second step, has been formulated, the failure rate has led to the outage of CBs, Then the failure rate, the repair time them are calculated also. In the third step, the reliability block diagram of CB is drawn based on the failure rate calculated in the second step. Based on the failure rate calculated from the reliability block diagram and with the help of the Reliability Calculation of Power System (RCoPS) program is written under the MatLab software, indexes of reliability of the substation terminals are calculated. In the fourth step, with regard to the output energy of each terminal from the substation, the Expected Energy Not of Supplied (EENS) and unreliability cost are calculated.

By creating electricity markets, regional electrical companies are working to reduce their current costs for greater profit and maintain Competitiveness strength. In this way, the reduction of maintenance costs, which is a significant part of the cost of operating the transmission network, has a much importance. On the other hand, electricity network equipment such as transformer, transmission lines and circuit breakers that have been exploited over the last few decades, naturally, With longer lifetime, have been aging. Consequently, regional electrical companies are now faced with a major challenge, such as aging equipment that to maintain the reliability of the system to an acceptable level and to escape the heavy costs associated with outages, they require a coherent planning for maintenance on the network. In the new competitive environment, regional electrical companies prefer to continue to use aging equipment as much as possible instead of replacing them with high costs by performing appropriate maintenances. In this paper, researches on determining the optimal rate of preventive maintenance, determining the priority of equipment for preventive maintenance and determining the importance of network equipment have been performed. In addition, statistical studies of the failure of khorasan regional electrical company substations for 16 years (2001-2017) have been carried out. By investigation the failure of the transmission and super distribution substations equipments, can be proposed a more comprehensive planning of maintenance of substation equipment, it is also possible to identify the critical points of the substations and prevent the outage of the equipment by performing proper maintenance. Finally, evaluation of reliability of substations with the use of smart grids and preventive maintenance models has been investigated with the help of Markov equations.

Today, nonlinear and harmonic loads have been extensively developed in electrical energy distribution grids. Nonlinear loads create harmonics in distribution grids. When condensing in distribution grids, we need to consider the inkjet flow harmonics to ensure that the capacitors used do not increase the harmonic distortion and consequently do not increase the losses caused by the harmonics. In this paper, the optimal location of fixed and switchable capacitors in harmonic distribution grids using the Crow Search algorithm (CSA) is investigated. Using the proposed algorithm, optimal location of capacitors to reduce losses and Improvement of the voltage profile is determined in two distribution networks of 15 and 34 bus standards of IEEE. The results of the algorithm used in this study are based on the results of other algorithms in references such as artificial bee colony (ABC), flower pollination algorithm (FPA), FA, and plant growth simulation algorithm (PGSA), and it is found that the results of the simulation indicate the efficiency and superiority of the pattern The proposed irritation is in comparison with other methods.

Forecasting the electricity price is important for electricity market players. Time series of the electricity price -as an inherently random phenomenon- have high uncertainty relative to the load. On the other hand, the non-stationary and non-linear characteristics of this time series make its forecasting difficult. On markets like the stock market, one can somehow forecast future price movements using technical analyses along with testing past prices and the volume of transactions. Therefore, this paper uses technical analysis indices for analyzing the time series data of the electricity market to forecast the electricity price. These indices are used as features extracted from time series of electricity price and applied to a Support Vector Machine (SVM) regression, through which the electricity price is predicted on daily horizon on Ontario electricity market.

In order to achieve the goals of restructuring in the electricity market of Iran, the stock exchange was launched due to its proximity to the full competition market and the prices set close to the equilibrium market. The benefits of trading in energy stocks include more transparency of information and prices, faster price discovery, price fluctuations based on market and industry realities, higher market liquidity and financing for producers, supplying energy to distributors and consumers, allowing more control over deals and tracking offenses. In the Iran electricity market, transactions outside the market include the liquidity of transactions before the physical delivery of electricity on the day of operation; and the plants will not be fined in the event of non-delivery of the traded power on the day of operation. Therefore, to maintain national capital, the verification and feasibility of delivery of negotiable capacity on the day of operation by the independent operator of the system is mandatory. This paper examines the effect of the constraints and restrictions mentioned in the electricity grid, especially the fuel constraints on allocating the maximum allowable production capacity to power plants participating in the Energy Exchange. For this purpose, the objective function is defined in two levels, which is optimized by integrating the LP-metric algorithm with the sum of weight coefficients and converting it into a single-level problem in GAMS software. The proposed method is tested on the IEEE 24-bus network and the numerical results are analyzed.