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Reliability is an increasingly important issue in power systems. As well known, problems in distribution systems are the main responsible of customer unavailability. In the last years, the utility interest in the improvement of the reliability in power systems is continuously growing thanks to the deregulation of the electricity market. It is known that inserting switches along the network positively affects the distribution systems reliability but, of course, it involves utility costs. This paper deals with the optimal choice of number, type and location of telecontrolled/automated circuit breakers and sectionalizers in distribution systems taking into account their cost. The optimization problem has been solved by means of a multi-objective evolutionary algorithm able to provide the minimum cost investment required to obtain a given network reliability, as well as the maximum reliability that can be achieved for a given economic investment.

The electrical potential around the conductors of a grounding system is computed by means of the hybrid FEM-DBCI method. The potential distribution on the earth surface is obtained directly as part of the solution, whereas the equivalent electrical resistance is computed in post-processing.

This paper compares the hybrid FEM-BEM and FEM-DBCI methods for the solution of open-boundary electrostatic field problems. Both methods couple a differential equation for the interior problem with an integral equation for the exterior one. The comparison shows that FEM-BEM is more accurate than FEM-DBCI but requires more computing time.

The optimal control strategy for autonomous micro-grids proposed in this paper highlights the possibility to minimize the overall micro-grid operating cost, minimizing at the same time the pollutants emissions and assuming that all the power made available by the renewable generators (photovoltaic and wind systems) and the storage systems is injected into the micro-grid. The proposed procedure is based on a hierarchical control architecture. The optimization procedure has been performed on a test micro-grid and verified by computer simulations. The numerical results show that the solutions found by the centralized optimization procedure can improve the micro-grid performances with respect to the ones that can be obtained from the generators local control.

The paper is intended to propose an optimal control strategy for autonomous micro-grids that focuses on the possibility to minimize the overall micro-grid operating cost, borne by the Micro-Grid Operator in order to provide power distribution to customers, while minimizing the pollutants emissions and assuming that all the power made available by the renewable energy sources is injected into the micro-grid. The proposed procedure can be implemented thanks to a hierarchical control architecture. The optimization procedure has been verified by computer simulations on a test network. The numerical results show that it is possible to find optimal feasible solutions that improve the operating conditions of the micro-grid with respect to the ones obtained as a result of the generators local control.

In this paper, stochastic optimization of the shielding of an axisymmetric induction heating system is performed by means of the self-adaptive low-high evaluations evolutionary algorithm (SALHE-EA). The finite element formulation of the electromagnetic problem is based on the magnetic vector potential. The hybrid finite element method Dirichlet boundary condition iteration (FEM-DBCI) method is used to deal with the unbounded nature of the field problem and to reduce the computing effort required for optimization.

This paper presents a new evolutionary algorithm (EA) for the optimization of electromagnetic devices called SALHE-EA (self-adaptive low-high evaluations – evolutionary algorithm). Its main aspects are identification of the optima of the objective function and evaluation of their sensitivity. Moreover, SALHE-EA works well if combined with the deterministic pattern search (PS) method, forming a good hybrid method. It performs well in the design of electromagnetic devices when the optimization of a multimodal function is required.

The aim of this article is to critically situate co-production methods such as that of the urban living lab within contemporary planning theory and in particular to the ideas of ‘agonistic planning...

In the automotive applications, especially in traction inverters for electrical vehicles, high power, efficiency, and reliability are fundamental targets. In this paper, an optimized layout of SiC-based power module able to limit the positive and negative transient gate-source voltages is proposed. The module design and features are firstly described, then SPICE-SIMetrix simulations on a layout without optimization are shown. Moreover, a description of the necessary guidelines to cope with transient negative and positive overvoltages phenomena is outlined. Finally, simulation test results on the optimized module layout are presented.