An Algorithm for the Protection of Distribution Feeders Using the Stockwell and Hilbert Transforms Supported Features

Faults’recognition in the distribution feeders(DFs)is extremely important for improving the reliability of the distribution system.Therefore,this paper proposes a technique to identify the faults on the DF using the Stockwell Transform(ST)dependent variance feature and Hilbert transform(HT)by utilizing current signals.By element to element multiplication of the H-index,we compute using HT aided decompositions of current waveforms and VS-index,and calculate through ST aided decomposition of current waveforms.By utilizing the decision rules,various faults are classified.Different faults studied in this work are line to ground,double line,double line to ground and 3-Φto ground.For high fault impedance,this technique is effectively utilized.Furthermore,variations in the fault incidence angles are also utilized to test the performance of the proposed technique.To perform the proposed algorithm,a IEEE-13 bus system is developed in MATLAB/Simulink software.The algorithm effectively classified the faults with accuracy greater than 98%.The algorithm is also successfully validated on the IEEE-34 bus test system.Furthermore,the algorithm was successfully validated on the practical power system network.It is recognized that the developed method performed better than the discrete Wavelet transform(DWT)and ruled decision tree based protection scheme reported in various literature.

Optimal Combined Heat and Power Economic Dispatch Using Stochastic Fractal Search Algorithm

Combined heat and power(CHP)generation is a valuable scheme for concurrent generation of electrical and thermal energies.The interdependency of power and heat productions in CHP units introduces complications and non-convexities in their modeling and optimization.This paper uses the stochastic fractal search(SFS)optimization technique to treat the highly non-linear CHP economic dispatch(CHPED)problem,where the objective is to minimize the total operation cost of both power and heat from generation units while fulfilling several operation interdependent limits and constraints.The CHPED problem has bounded feasible operation regions and many local minima.The SFS,which is a recent metaheuristic global optimization solver,outranks many current reputable solvers.Handling constraints of the CHPED is achieved by employing external penalty parameters,which penalize infeasible solution during the iterative process.To confirm the strength of this algorithm,it has been tested on two different test systems that are regularly used.The obtained outcomes are compared with former outcomes achieved by many different methods reported in literature of CHPED.The results of this work affirm that the SFS algorithm can achieve improved near-global solution and compare favorably with other commonly used global optimization techniques in terms of the quality of solution,handling of constraints and computation time.