economic dispatch

Planning the unit commitment (UC) is one of the useful and practical methods to reduce generation costs and increase the lifespan of equipment and optimal use of the power network. UC is a non-linear, discontinuous and important problem in the operation of power systems, which is highly complex due to its many limitations and parameters. In this paper, first the UC problem is introduced and all the existing limitations are checked, then the linearization of the problem is discussed, in which case all the nonlinear factors are properly linearized. In the following, the proposed optimal scheduling framework is investigated and modeled under different scenarios on the IEEE 6-bus system. In the first scenario, the problem is investigated in a non-linear way and different modes are investigated, including the effect of the shutdown time of a power plant at the beginning of the planning time. In the second scenario, the linearized problem is investigated and then compared with the nonlinear case. But, one of the most important influencing factors in the planning of the units is the examination of the line outage, which is added as a constraint to the optimization problem and is examined in the third scenario, which in the first mode the line outage between bus 1 and 4 and in another mode, the line outage between bus 1 and 2 is considered. The results show that when the lines outage from the grid, the cost of production and operation of the power system increases. In this paper, the problem is modeled as MILP in GAMS software and solved by CPLEX solver. The results are compared in two normal and abnormal network (line outage) modes. The simulation results show the superiority of the proposed strategy and the reduction of the generation costs of power plants during 24 hours a day.

Economic Dispatch for power systems with the aim of optimizing the total production cost for active units in the power network is one of the most important topics for today's modern systems. In other words, the purpose of the economic Dispatch problem is optimal and appropriate planning for production units, taking into account the nonlinear factors and limitations in the power network and production units. And it plays a very important role in the economic exploitation of power systems Solving the problem of economic Dispatch optimization is very complex due to the huge dimensions of the nonlinear objective function, various restrictions and limitations. However, the use of optimization algorithms and artificial intelligence has been used to solve this problem. In this research, based on the use of a new algorithm called search and rescue, which is modeled based on the individual and group behavior of humans in searching for an individual or a group that has had an accident or is lost. This algorithm has great power in solving problems with high constraints, which can ignore local optima to confirm the proposed method in minimizing the cost and pollution of simulation in the software environment (MATLAB) on test networks (3, 6, 10) units done and the simulation results obtained from the proposed algorithm show that the accuracy and speed of finding the answers have been improved with this method.

Due to the significant growth of load in the power industry as well as the high penetration of wind turbines (WTs) in power systems, the issue of unit generation (UC) planning has become a critical issue. UC determines the problem of planning the production of units, the time when units are turned on and off, and how to distribute the load between the units that are turned on so that the cost is minimized; Therefore, the main focus of this article includes two scenarios that examine the production planning of units with different constraints, including the slope rate and the production prohibited area in the presence and absence of WTs; Therefore, at first, the production planning of the units is done by considering the load of future hours, which increases the reliability of the planning and also minimizes the costs. In the second part, a method for planning the production of units is presented, in this method, the minimum shutdown time of the units is also included in the objective function, in fact, the start-up costs are considered hourly. This proposed method changes the production planning pattern so that the costs are reduced. Finally, the implementation of the problem is done in two scenarios considering wind turbines and the absence of wind turbines.

Abstract: In traditional generation systems, energy from fuel is simply converted into electrical energy, while in the combined heat and power (CHP) systems, fuel energy, in addition to generating electricity, also generates thermal energy. Therefore, the efficiency of these systems is considerably higher than traditional systems, and this justifies the need for CHP systems. The emergence of CHP systems alongside fossil fuels power plants makes the economic dispatch of power and heat between the energy generating units with the lowest cost one of the important issues of power systems utilization. In this regard, the need to consider emissions from energy generating units along with other operational constraints of power plants complicates the economic dispatch. The presence of multiple objective functions, and in some cases opposites, transforms the above problem into a multi-objective optimization problem. This paper, while investigating the problem of economic dispatch of load in power plants along with the CHP and heat generating units, uses the meta-heuristic method of multi-objective harmony search algorithm (MOHS) in solving the problem of economic power and heat dispatch. To demonstrate the efficiency of the proposed method, a system with 4 units of electric power generation, 2 units of CHP and one unit of heat generation is used. The performance of the proposed algorithm is shown by comparing with other advanced multi-objective optimization methods such as NSGA-II and MOPSO.

Energy efficiency of power plants is less than 60% However, the efficiency of the CHP units can be up to 90 %.CHP units in addition to high efficiency, They reduce environmental pollutants by 13 to 18 percent. The purpose of this thesis is to use the simultaneous power and power generation plants to reach the optimal economic destination for Genco And to maximize economic profit And to minimize environmental releases based on the integration of CHP systems with conventional heat generating units on the power grid The Crow Search Optimization algorithm (CSA) is used to solve the economic load distribution problem (CHPED) And the problem of the economic load distribution (CHPEED) as well as the problem of economic load distribution with the participation of electricity services market in MATLAB software simulation and its results for all three modes are presented. The proposed method is used for ten power plants with different characteristics with variable load The results of the Csa approach for optimization based on comparison with the results of the Ant colony algorithm as well as other algorithms considered in other studies are valid. When the CHP units are integrated with the integrated system of 10 TG, the results of the implementation of the proposed approach are very promising.