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During last few eras, restructuring has surpassed all possible areas comprising the electric power supply industry. Restructuring has carried out significant advantages such that an electricity is nowadays a commodity. Competitive market also paved way for numerous participants. This leads to congestion in transmission lines. Furthermore, transmission network in open access has strengthened the congestion...
In this paper, the combination of fuzzy logic controller and genetic algorithm are proposed. A fuzzy control system is a control system based on fuzzy logic a mathematical system that analyzes analog input values in terms of logical variables. The purpose of fuzzy system is to determine the capacity of interline power flow controller (IPFC) in terms of voltage deviation. The optimal location of IPFC...
The renewable sources' influence regarding the distribution network expansion planning is tackled. The network expansion is discussed in two cases: with and without renewable sources. The obtained expansion solutions are analyzed and a final one is proposed by the authors. To achieve this goal network reconfiguration and N−1 contingecies are performed. The goal is to supply all the consumers for each...
Network reconfiguration, shunt capacitors, and distributed generators are less expensive options to distribution system expansion. The study of simultaneous use of network reconfiguration, optimal capacitor placement, and optimal distributed generator siting has been limited to the investigation of only two objectives, without regard to the conflicts among the system objectives. This study optimizes...
Wheeling is a process of transmitting electric power through the transmission lines governed by a third party. A practical problem is that wheeling from vendor to vendee involves power flows through several intermediate networks that is, multi-area wheeling. Each utility involves in part of a more number of wheeling transaction over a few miles or hundreds of miles. A vendor that generates power does...
A transmission loss minimum re-scheduling method by genetic algorithm and modified shuffled frog leaping algorithm are proposed. The problem is a complex mixed integer programming problem. A genetic algorithm (GA) is a search or optimization algorithm based on the mechanics of natural selection and natural genetics where modified shuffled frog-leaping algorithm (MSFLA), which is an improved version...
This paper presents evolutionary computation (EC) techniques and discusses their applicability to the optimal power flow (OPF) problem. The power flow problem is optimized to find the minimum fuel cost of all generating units while maintaining an acceptable system performance in terms of limits on the power outputs of generators, bus voltage and line flow. Different EC techniques such as genetic algorithm...
After Optimal distribution substation locating, distribution feeder line planning remains the main problem in distribution system planning. Therefore, a MST-based and new GA algorithm for distribution network optimal planning is presented. To reduce computational time and avoid infeasible solution, two new operators are introduced to ensure that all individuals are feasible solution. Meanwhile, an...
With the electricity market deregulation, the number of unplanned power exchanges increases. If these exchanges are not controlled, some lines may become overloaded. Network contingencies often contribute to overloading of branches, violation of voltages and also leading to problem security. This paper presents a procedure based on the contingency severity index (CSI) described by a real power flow...
Network reconfiguration and capacitor placement have been widely employed to reduce power losses and to maintain voltage profiles within permissible limits in distribution systems. Reconfiguration method that is employed in this paper is based on an improved simple branch exchange method of single loop that is performed in a previous work. In this paper a joint optimization algorithm is proposed for...
This paper proposes an improved method for reconfiguration of distribution systems based on a simple branch exchange method of single loop. In some previous works for reconfiguration of distribution networks with several loops, loops are one by one selected and reconfiguration at each matched loop is performed according to the simple branch exchange method of the single loop. Although the loops selection...
After blackout, power system reconstruction is a multiobjective optimization problem, especially for parallel restoration through power system partitioning. It includes optimal system partitioning strategy, units optimal starting-up sequence, time requirements for system reconstruction. A constrained multiobjective optimization model is proposed for power system reconstruction. Fast and elitist non-dominated...
The integration of Distributed Energy Resources (DER) in power systems presents substantial challenges to network planners. Assessing accurately the impact that DER will have is critical, as the specifics of the installed DER may affect: control of the network within limits; quality of supply; losses and financial objectives. The optimal placement and size of DER in a distribution network is desirable...
Quantum Genetic Algorithm (QGA) is a genetic algorithm (GA) based on principles of quantum computing (QC). It uses quantum bit coding, whole interference crossover and quantum gate as update operator to complete evolution search. Compared with conventional GA, QGA is characterized by small population size, rapid convergence and strong global search capability. In this paper, QGA is applied in power...
Transmission loss and load flow allocations become important issues under deregulation system. Due to nonlinear nature of power flow, tracing the loss and power flow through the mesh network becomes more complicated. Since the complexity of electricity transmission system, it is not straightforward to determine the contribution of particular generator to a particular line loss and/ or load. This paper...
The use of the Evolutionary Computation (EC) grew in interest recently. Among various Evolutionary Computation approaches, Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) are used in optimization problems; they have much in common but also have some differences. This paper presents a decision support tool based on Particle Swarm Optimization Technique (PSO) and Genetic Algorithm Technique...
The introduction of distributed generation (DG) into distribution networks has a significant effect on losses. This effect can be detrimental or beneficial depending on where DG units are allocated and which sizes they have. This paper deals with optimal siting and sizing of DG units for minimizing the total power losses in a radial distribution network under bidirectional and unidirectional power...
This paper describes a new approach to the problem of the REI equivalent design, employing genetic algorithms. The optimum design of the REI equivalent aims to determine the number of REI buses to be used and the aggregation of external buses into the REI buses, using the minimum line power flows absolute errors in the internal system as optimization criterion, over a set of simulated node and branch...
Distribution network reconfiguration (DNR) is a crucial issue in the operating horizon of distribution systems. In distribution networks tie switches will be changed to obtain an appropriate network configuration with minimum losses. Distribution networks have hundreds of switches and determining the best status of switches is a complicated combinatorial, non-differentiable constrained optimization...
The main disadvantage of GAs is the high CPU time execution and the quality of the solution deteriorate with practical large-scale optimal power flow (OPF) problems. This paper presents an efficient parallel GA (EPGA) combined with fuzzy practical rules for the solution of the large-scale OPF. The length of the original chromosome is reduced successively based on the decomposition level and adapted...
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