فهرست مطالب mohsen kalantar

Due to renewable generation increment in power systems and the complexity of control and protection of them, the evaluation of   transient stability is necessary. This paper aims at analyzing the impact of wind power generation on the transient stability of power systems. To this end, doubly fed induction generator (DFIG) converters were first investigated in a closed-loop control mode. More detailed controls were used for the rotor side converter. Controls of the DC link converter on the network side were assumed to be ideal. Then, through using Gershgorin's theory, a new approach to adjust converter control parameters was presented. The simulation results in different operating modes confirmed the capability of this method in adjusting the converter’s control parameters. Also, by using performed simulations, the effect of increasing wind power production penetration and the changes of reactive power compensation by DFIG on the transient stability of power system were investigated. Finally, the effect of power system strength and DFIG parameters change, in the presence of DFIG-based wind power generation, on transient stability was analyzed. The simulation results showed that an increase in wind power generation initially led to an improvement and finally to the weakening of the transient stability of the system. In fact, this paper provides a professional and valuable perspective towards the investors and operators of the power systems with wind power generation from the viewpoint of transient stability.

Introduction of new technologies such as energy storage systems, electric vehicles, and distributed generation improved the characteristics of networks. On other hand, using these components in distribution systems improves system performances such as power losses. One of effective methods for improving system characteristics is distribution network reconfiguration. In this study, in addition to these effects, the role of reconfiguration in improving system resilience is investigated. Accordingly, a comprehensive model for network reconfiguration in the precense of energy storage systems, electric vehicles, wind turbines, and photovoltaic generation is proposed. Regarding this, the optimal location and capacity for optimal operation of system is obtained for all mentioned components. The effectiveness of model is proved in four case studies, The results of the four modes are compared. The results show the effect of network reconfiguration and storage components on the outputs of the model. The model is implemented on the 33 IEEE network in the GAMS environment with Sbb solver.

In this paper, the optimal allocation of battery energy storage in the distribution network is performed for peak shaving and maximizing profitability. To this end, indicator shave been introduced using hourly load information, feeder upgrade cost and electricity sales price to various tariffs. Then, using the Analytic Hierarchy Process (AHP), the indicators are weighted and a suitable feeder is indicated for installing energy storage. Then, to achieve the maximum possible peak shaving and maximize profit, an economic objective function is defined to determine the optimal sizing and charge-discharge of the energy storage. The objective function includes the investment and operating cost of battery energy storage and the profits of energy arbitrage, deferring facility investment, environmental issues, and reducing the upstream access cost. Appropriate constraints are considered according to the peak shaving, range of battery power and energy capacity as well as balance in the amount of charge and discharge. Due to the nonlinearity of the objective function, the components involved in the nonlinearity of the objective function are determined according to the heuristic algorithms (Genetic Algorithm (GA), Particle Swarm Optimization (PSO), Ant Colony Optimization (ACO), and Tabu Search (TS)) and then the objective function is solved by the Interior-point linear programming. The results provide the most suitable battery type and optimization method among the introduced batteries and methods while fulfilling the objectives.

In this paper, new reactive power market structure is studied and presented. Active power flow by itself causes active and reactive losses. Considering reactive losses of active power flow in the reactive power market without paying any costs is the main purpose of this paper. For this purpose, new methodology for reactive power market structure is proposed. Hence, this study tries to improve reactive power market and create fair competition in reactive power generation through modifying the market structure. The advantage of this method is determining the mandatory region of units based on both active power output and its distance from the load. In order to stimulate the proposed method, IEEE 24 is used, and this method is compared with each the conventional reactive power market. As it will be shown, the total payment by ISO will be reduced by using this method.

In this paper, a new structure for reactive power market is presented. Considering reactive power losses caused by active power flow in the reactive power market is the main purpose of this paper. Hence, this study tries to improve reactive power market and create fair competition in reactive power generation.

In this paper, a new reactive power market structure is studied and presented. Active power flow by itself causes active and reactive losses. Considering such losses after active power market clearing and in the reactive power market procedure without paying any costs is the main purpose of this paper. For this purpose, new methodologies for reactive power structure are proposed which the reactive losses are considered before market closing. Hence, this study tries to improve reactive power market and create fair competition in reactive power generation through improving the market structure. Also, in this work, the cost payment function of synchronous generators, which has an important influence on reactive power market, is modified. In order to stimulate and describe the proposed methods in the implementation of reactive power market, Cigre 32 bus test system is applied and the proposed methods. As will be shown, the total payment by ISO will be reduced by using the proposed methods.

One of the basic obstacles in the deployment of the clean technologies such as wind turbines or PV modules is their intermittent nature due to dependency to the wind speed and solar radiance. The authors in this paper aim to analyze the effect of the clean technologies such as wind turbines and PV modules in the total and individual costs of the distribution system. In order to model the uncertain nature of the clean technologies, a probabilistic method is proposed in this study. So, a DG planning problem based on the hourly variations in the wind speed and solar radiance in order to reduce the total cost of the distribution system is proposed. The hourly variations of the load as well as the hourly variations in the wind speed and solar radiance is considered. All of the defined economic, technical and environmental functions are turned into cost functions. An encouraging and punishment mechanism is defined beside the other cost functions. The planning problem is formulated as mixed integer nonlinear programming problem (MINLP). The proposed method is applied on the 9-bus distribution system and the results show a significant reduction in annual costs of the distribution system in presence of the DG units.

Due to the increasing interest on renewable sources in recent years, the studies on integration of distributed generation to the power grid have rapidly increased. In order to minimize line losses of power systems, it is crucially important to define the size and location of local generation to be placed. Minimizing the losses in the system would bring two types of saving, in real life, one is capacity saving and the other one is energy saving. In this paper, our aim would be optimal distributed generation allocation for voltage profile improvement and loss reduction in distribution network. Harmony Search algorithm (HSA) was used as the solving tool; the problem is defined and objective function is introduced according to losses, security and cost indices. The applied load flow method is based on the equivalent current injection that uses the bus-injection to branch-current (BIBC) and branch-current to bus-voltage (BCBV) matrices which were developed based on the topological structure of the distribution systems. This method is executed on 13 bus unbalanced distribution system and show robustness of this method in optimal and fast placement of DG, efficiency for improvement of voltage profile, reduction of power losses and cost.