M. A. Elhameed

Water cycle algorithm-based economic dispatcher for sequential and simultaneous objectives including practical constraints

Abstract The article presents an efficient methodology based-on water cycle algorithm (WCA) to solve single and multiple objectives of economic load dispatch (ELD) aiming to generate the optimal value of the active generated power for each unit. Three objectives are adopted for optimisation either sequentially or concurrently; they are: (i) fuel cost considering valve-ripple effect, (ii) emission rate, and (iii) total network loss. The generating unit prohibited zones along with ramp rate limits and generating unit power limits specify the inequality constraints of the problem while maintaining system power balance. Usually, optimisation of simultaneous multiple objectives produces set of non-dominated Pareto-front solutions. To help the decision maker, the best compromise solution is carefully picked among optimal Pareto-front points. The proposed WCA-based methodology is demonstrated on three test cases with various complexities and under number of objective scenarios. Numerical results and further subsequent comparisons to other challenging optimisers indicate the viability and confirm the strength of the proposed WCA-based ELD method.

Improved performance of PEM fuel cells stack feeding switched reluctance motor using multi-objective dragonfly optimizer

In this article, a switched reluctance motor (SRM) powered by autonomous stacked proton exchange membrane fuel cells (PEMFC)’s stack with the purpose of optimizing their operating performances is addressed. Three key performance indices are examined that include: (1) torque per ampere ratio, (2) torque smoothness factor and (3) average starting torque. The later mentioned adapted indices characterize the objective functions that can be optimized individually and concurrently using a novel application of multi-objective dragonfly approach (MODA). The MODA is applied to generate the optimal turn (on/off) angles of H-bridge converter and the gains of a proportional-integral speed controller. A Pareto front optimal solutions are made, and the final best compromise solution is carefully chosen. The terminal voltage of the PEMFC is fine controlled by a boost converter, to overcome the noticeable decline of its voltage profile with the increase in loading current. The system under study is demonstrated at various loading conditions with necessary comparisons to other recent competing methods complete with subsequent discussions. The cropped numerical results indicate that PEMFC energy saving, reduction in SRM torque ripples and PEMFC current ripples can be enhanced. In addition, higher average starting torque of the SRM is realized.