In a smart platform, the passive management of the distribution systems changes into active management. Active distribution systems require high-precision real-time control, which is provided by the new structure of Wide Area Measurement, Protection and Control (WAMPC). The main components of the WAMPC system are the Phasor Measurement Units (PMUs). Micro Phasor Measurement Unites (μPMUs) are new generation of PMUs, which specifically designed for use in distribution systems. In this thesis, the problem of optimal μPMUs placement for full observability of smart distribution systems, is solved. For solving this problem, the available models for optimal placement of PMUs in symmetrical three-phase transmission systems, are developed to include some of distribution system's features. In this regard, with considering the radial structure of distribution system and it's many branches and as a result existence of zero injection buses adjacent to each other, or existence of radial (terminal) buses adjacent to zero injection buses, new creative rules for restricting the search space and for reducing the number of μPMUs, are presented. The objective function, is minimizing of the total costs, includes the cost of μPMUs and the cost of Potential and Current Transformers (PT & CT), that are necessary for connecting each bus and each line to μPMU, respectively. The existence of conventional measurements is considered in proposed model. Furthermore, single μPMU outage contingency, as well as limitation of measurement channels of μPMU are considered. Since some of buses in distribution systems, have single-phase or two-phase loads, or in some area the connections between buses are single-phase or two-phase, the proposed model, is developed to include the asymmetric property of distribution system. In this part, a combination of single-phase and three-phase μPMU are optimally placed. Additionally, with development of the effect of zero injection buses in symmetrical mode to zero injection phases in asymmetrical mode, the effect of asymmetrical systems' zero injection phases is used in optimal μPMUs placement. In this mode, objective function is minimizing the total costs and the costs of auxiliary equipment (PT & CT) are combined in the cost of μPMUs. Moreover, in this mode, single μPMU outage contingency, as well as limitation of measurement channels of μPMU, are modeled. The proposed model, is formulated as an Integer Linear Programming (ILP) problem and is solved with GAMS software and MATLAB software. The 13, 34 and 37 buses IEEE standard test distribution systems are analyzed in several cases to exhibit the efficiency of proposed model. The numerical results are compared with some references, too. In all cases the obtained numerical results demonstrate the validation of proposed model.

In this dissertation, a new model is developed to determine the optimal size of equipment of a CCHP system, to supply the electrical, heating, and cooling needs of a residential complex, which can, in addition to determine the size of the equipment of the system, also determine the optimal operation esterategy. This system includes a Prime Mover kind of Reciprocating internal combustion engine, a backup boiler, a heat exchanger, and an absorption chiller. The objective function of this model is to minimize capital costs and maintenance and operation costs of the CCHP system. Operating costs include the cost of fuel, the cost of emission of pollutants and the cost of revenue generated by the exchange of power with the network over the lifetime of the project.The most important constraints of the problem is the balance between electrical and thermal power. The proposed model is formulated as a nonlinear optimization problem mixed with an integer of the type of dynamic problem. To solve the problem, a new, simple and straightforward method is presented as a combination of mathematical methods and evolutionary methods. For this purpose, the GAMS and MATLAB software links are used. Finally, the proposed model is tested on four residential complexes in Khuzestan province and the results are presented. Based on the results, Following thermal Load opearation in the small residential complexes in Khuzestan province is more efficient. Also, hybrid operation in the large residential complexes of this province, is more economical

In this thesis, a model to exploit optimally a CCHP system to meet the needs are presented of a common energy industries. CCHP system is consists of a CHP unit with an absorption chiller, an electric heating pump, an auxiliary boiler and a storage of electrical energy. It is assumed joint and can be connected to the national electricity grid electrical energy market hours on prices, exchange with the upstream network. It is also assumed that part of the joint flexible electric demand And can be moved between the hours of day and night with the assumption that the total daily energy expenditure must remain constant. This thesis, CCHP system operators with the above hypothesis by a nonlinear mixed-integer programming problem has been solved modeling and software GAMS. Optimized for a common industrial problem under control In hybrids and gas price levels for different scenarios, presence or absence of restrictions on the power exchange with the network upstream presence or absence of various amounts of time removable and common energy needs. The results are analyzed.

The load flow is one of the analytical instruments that is used for determining the static behavior of distribution systems during designing stages, network developing, and operation. In traditional distribution load flow algorithms, the substation has the duty of supplying of slack power in the system. Since in restructured systems, technical or economical limitations confine the sending of bus slack, using single slack distribution is not suitable. Considering the increased influence of the distributed generation units in the distribution network, in modernized load flow in addition to the substations, DGs also share in supplying of the slack system. In this study, a new model of three-phase unbalanced load flow of distribution network with distributed slack, based on the backward-forward algorithm with power summation was presented. The substation bus and DG units with PV control as participating DGs are considered as real power slack distribution. In suggested model, first with determining the active power flow direction, the scope of each generator domains becomes specified. Then, by using generator commons concept, the participation factor and the share of each DG in supplying the slack of the active power system will be determined. The suggested load flow algorithm was run by MATLAB software and administered by modified 34 bus test system under different scenarios and the results were analyzed. The results clearly show the efficiency of the suggested load flow with distributed slacks.
 

Practical power hydro power plants in Iran is 17 percent of the total. Dam of power plants are mainly focused in the area of Zagros. The power plant cascade into the catchment area of Karun, Dez and Karkheh have been built. In a restructuring electricity industry (such as Iran's electricity industry), power plants through the bid to the wholesale market daily, can sell their products. Therefore, each plant depending on the features, costs and limitations and to achieve higher profits, a proposed strategy of making that known under its short-term planning. When a cascade basin as there are numerous plants, the complexity of production planning is Constraints units and relations reservoirs upstream and down and to influence Self-Scheduling of each plant. Therefore, the bidding of the power to participate in the electricity market takes at the same time. Khuzestan Water and Electricity Organization on behalf of hydroelectric plants is covered in the electricity market so be efficient methods of modeling all the factors affecting Self-Scheduling, taking into account technical and economic aspects be used. This dissertation addresses the self-scheduling of a hydro generating company in a cool-based electricity market. This company comprises several cascaded plants along a river basin. The objective is to maximize the profit of the company from selling energy in the day-ahead market. Additionally, start-up costs due mainly to the wear and tear are considered. Finally, different realistic case studies are analyzed in detail. Constraints can be traced including hydraulic limitations and curves Hill chart. In order to reduce power dissipation caused by frequent switching on or off in the summer, start-up costs have been included in the model. In order to assess the problem Self-Scheduling, two sets of power plant water cascading over a area studied and the results are presented. The first system includes eight plants in the catchment area of a river in Spain and the second system includes three stations in Karun Basin in Iran. The results in all cases simulation shows the effectiveness of the algorithm.

In this thesis optimized placement of sectionalizing switches in radial distribution systems are investigated. In distribution systems, switches are used by network operators for amelioration in network reliability in the time of fault occurrence and also for determining the optimized network configuration in normal conditions. Therefore, it is of vital importance that in switch placement problems both of application should be taken into account. Regarding mentioned issue, in this thesis a novel method has introduced for optimized sectionalizing switches placement in radial distribution systems which not only determines the switches’places for increasing the network reliability but also it will settle their open and close pattern in cold and warm seasons for steady state system. Proposed model is formulated in the form of a constrained multi-objective optimization problem. Objective functions for this problem are as follows: minimizing purchase costs, switches’ installation and maintenance, minimizing expected cost of energy not supplied (As an index for network reliability) and minimizing the cost of energy losses in normal condition which is affected by network configuration. The optimizing constraints are the maximum number of placed switches considering budget limitation for Distribution Company, voltage and current limitations and preserving the radial structure while determining the optimized configuration in network. The problem has been solved by applying multi-objective Genetic Algorithm with Non-dominated Sorting (NSGA-II). In addition, actual realities (particularly Khouzestan Province Distribution Company) such as real residential, business, administrative and education customer profiles in both cold and warm seasons are considered. Proposed model is implemented and results are reported on a test network with 32 buses in different scenarios. It is worth noting that in all tests results have proved the performance of the model.

In power systems with high penetration of renewable energy sources, providing Ancillary Services to make load-balancing network produced a serious challenge to the operator system. One of the main features of smart grid demand response is to maintain a balance between production and demand effective. We provide Ancillary services frequency of demand response in the context of an smart grid is considered. Set the frequency of the energy-storing sensitive responsive loads (such as electric water heaters) are used to adjust the frequency. Trigger frequency is the frequency at which the equipment is turned on or off state is determined in a process of optimization. Depending on the frequency deviation from the nominal value, the number of facilities from on to off or vice versa, and thus responsive loads switching frequency can help to stabilize. To evaluate the simulation algorithm to determine the optimal trigger frequency of equipment two aggregator with five and 50 equipped studied and the results of the analyzes presented. The results in all cases, the simulation shows the effectiveness of the algorithm.