This paper presents a positive approach in an optimized design of a combinatory unified power-quality conditioner (UPQC) and superconducting fault current limiters (SFCLs). This is based on a normalized simulated annealing algorithm compared with analytic hierarchy process objective optimization. The optimization algorithm for simultaneous optimization computes and produces three-dimensional alignments in Pareto front at the end of the optimization run. The results show that the SFCL can reduce the volt-ampere rating of the UPQC by limiting the fault current, thereby reducing the cost of UPQC installation. The aforementioned algorithm requires advanced numerical techniques for simulation studies by PSCAD/EMTDC on a sample distribution system for determining a global optimal combination of UPQC and SFCL by considering individual parameters and accounting for the constraints, which is the main motivation of this paper. This will result in a more thorough knowledge of "scaling factors" and the system quality mechanism which will enable the most efficient systems from the viewpoints of cost cutting, energy savings, and downsizing.Index Terms-Analytic hierarchy process, multiobjective decision making, power quality (PQ), simulated annealing, superconducting fault current limiter, unified power-quality conditioner (UPQC).

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Here, different feasible configurations of passive permanent magnet bearings (PMBs) are presented and compared with each other. In these configurations, stiffness is improved by adding iron cores and air intervals between magnets. Bearings with opposite magnetisation stacking (standard) and rotating magnetisation stacking (Halbach) are studied here. A twodimensional planner model is used to calculate the magnetic field and stiffness. The optimisation will be performed for obtaining maximum stiffness per magnet volume ratio. The results show that standard stacking with radially magnetised PMs and having back iron and air intervals between magnets is the most optimum structure. For larger dimensions of magnets, other structures will be useful too.

Abstract-This paper presents a hybrid numerical approach combining an improved Time Domain Finite Element-Boundary Integral (FE-BI) method with Time Domain Physical Optics (TDPO) for calculations of electromagnetic scattering of 3-D combinativecomplex objects. For complex-combined objects containing a small size and large size parts, using TDPO is an appropriate approach for coupling between two regions. Therefore, our technique calculates the objects complexity with the help of FE-BI and the combinatory structures by using of the TDPO. The hybridization algorithm for restrictive object is implemented and the numerical results validate the superiority of the proposed algorithm via realistic electromagnetic applications.

AC loss is one of the important parameters in HTS (high temperature superconducting) AC devices. Among the HTS AC power devices, the transformer is an essential part in the electrical power system. The AC losses in an HTS tape depend on the magnetic field. One of the techniques usually adopted to mitigate the unwanted magnetic field is using a system of coils that produce a magnetic field opposite to the incident one, reducing the total magnetic field. In this paper adding two auxiliary windings to the HTS transformer to produce this opposite magnetic field is proposed. The proper use of these auxiliary windings could reduce the leakage flux and, therefore, the AC loss. A mathematical model is used to describe the behaviour of a transformer operating with auxiliary windings, based on the theory of electromagnetic coupled circuits. The influence of the auxiliary windings on the leakage field is studied by the finite element method (FEM) and the AC loss of an HTS transformer was calculated. Also, the simulation results show that employing auxiliary windings will improve the HTS transformer efficiency.