Continuous firefly algorithm for optimal tuning of PID controller in AVR system

This paper presents a tuning approach based on Continuous firefly algorithm (CFA) to obtain the proportional-integralderivative (PID) controller parameters in Automatic Voltage Regulator system (AVR). In the tuning processes the CFA is iterated to reach the optimal or the near optimal of PID controller parameters when the main goal is to improve the AVR step response characteristics. Conducted simulations show the effectiveness and the efficiency of the proposed approach. Furthermore the proposed approach can improve the dynamic of the AVR system. Compared with particle swarm optimization (PSO), the new CFA tuning method has better control system performance in terms of time domain specifications and setpoint trackin

Conception optimale des systèmes de production par une approche bésée sur une système colonie de fourmis artificielles

111 p. : ill. ; 30 cmThis work is devoted to the dispatching of the reactive power and the maintain of voltage profile in the electrical network power systems in steward state by a hybrid approach. Combining heuristic and numerical technique has been chosen. The considered approach deals with the security problem, mainly the elimination of voltage constraint voilation disturbances. Firstly, the effect of the reactive power transmission upon the voltage drop and the active power losses has been analysed. Two important proprieties have been extracted; these will be used in the devlopment of the approach

Maintien des tensions et gestion de la puissance de la réactive dans les réseaux de transport par une approche hybride

ill

Improved Cuckoo Search Algorithm for Document Clustering

Efficient document clustering plays an important role in organizing and browsing the information in the World Wide Web. K-means is the most popular clustering algorithms, due to its simplicity and efficiency. However, it may be trapped in local minimum which leads to poor results. Recently, cuckoo search based clustering has proved to reach interesting results. By against, the number of iterations can increase dramatically due to its slowness convergence. In this paper, we propose an improved cuckoo search clustering algorithm in order to overcome the weakness of the conventional cuckoo search clustering. In this algorithm, the global search procedure is enhanced by a local search method. The experiments tests on four text document datasets and one standard dataset extracted from well known collections show the effectiveness and the robustness of the proposed algorithm to improve significantly the clustering quality in term of fitness function, f-measure and purity

Hybrid approach for redundancy optimization of multi-state power system

This paper presents an optimize method of the well known Redundancy Optimization Problem (ROP) using a combined ANT Colony System (ACS) and Universal Moment Generating Function (UMGF). The ACS searches for the minimum cost solution by selecting the appropriate components for a series-parallel system, given a minimum system reliability constraint. The UMGF is used to estimate the system reliability value during search. This approach is an example of a computationally efficient method to apply ACS optimization to problems for which repeated calculation of the objective function is impractica

A novel fault location approach for radial power distribution systems

Power distribution systems (PDS) are increasingly complex and spread over long distances and in different locations. Given their radial configuration, the loads could be inserted at the same distances from the substation. This leads to multiple estimation of fault location (FL) and yields time consuming for iterative FL algorithms. In this article, we provide a novel practical approach to fault localization in order to defeat these limitations. The central idea of the proposed approach is to divide the multilateral distribution system into a possible number of mono-lateral sub systems (MLS) using a proposed communicating sensor. Next, we apply two different fault locator algorithms only to the defective MLS. The first variant of the approach is based on the impedance method, while the second variant is non-parametric used only when there is lack in the line data. To test the proposed technique in practice, we used the IEEE 13 Node test feeder, and a real Algerian PDS. The results obtained clearly show the contribution of the dedicated method for locating faults in the PDS