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This article is the continuation of graph sets method (GSM) proposed in the companion paper Part I for deriving equations and analyzing multicoil wireless power transfer multicoil (MC) wireless power transfer (WPT) systems. After explaining GSM, categorizing WPT coils into three different types, and proposing some approximation techniques in Part I, this article, as the second part of this work, presents numerical simulations and experimental results for a three-coil MCWPT system similar to what is explained in Part I. The simulations are conducted in MATLAB/Simulink and ANSYS environments, and for the experimental model, three ferriteless cylindrical coils are built and compensated to behave as voltage driven, current driven, and passive coils, respectively, at the specific frequency of 200 kHz. After analyzing and comparing the simulation and experimental results, it is shown that GSM can be an effective and illustrative technique that facilitates comprehensive analysis of interactions amongst the coils and their characteristics, especially when WPT systems contain multiple coils. [ABSTRACT FROM AUTHOR]

In this paper, a novel converter is presented to improve the excitation process in switched reluctance generators (SRGs). Accumulator capacitor converter (ACC) is based on a singular scheme of flyback converters. ACC performs two main roles. First, in an initial step, it charges an accumulator capacitor with a determined value of voltage; then, during the magnetizing period, it discharges the stored energy into machine coils. Therefore, ACC provides the SRG with a determined magnetizing energy and uses the forced magnetizing phenomenon to magnetize its coils. The processes yield some outstanding superiority such as excellent operation at high speeds, simple controlling scheme, lower stress on the excitation source, etc., over conventional converters. To analyze the performance of ACC, the required analytical expressions for charging the capacitor and discharging it into the coils are developed and the constraints for switching periods are demonstrated in detail. Afterward, through MATLAB/Simulink and finite-element analysis (FEA) simulations, its operation is evaluated and compared to conventional asymmetric bridge and bifilar converters (BFCs); moreover, its test bed is assembled and tested experimentally, and its results, along with the simulation ones, validates ACC performance. [ABSTRACT FROM PUBLISHER]

Abstract—In this article, a comprehensive method is introduced to redress eccentricity fault consequences. Two main effects of eccentricity faults include considerable increase in unbalanced magnetic force and torque ripple. Dependency of unbalanced magnetic force and torque ripple on eccentricity fault level is shown, and the possibility of compensating them via controlling currents in facing poles is proved. These objectives are accomplished through a novel converter that controls currents in poles of every phase such that one pole is responsible for nullifying unbalanced magnetic force and the facing pole is in charge of torque ripple reducing. The control algorithm is analyzed in details and through finite-element method and MATLAB/Simulink (The MathWorks, Natick, Massachusetts, USA) is implemented on a 6/4 switched reluctance motor with 30% eccentricity fault level. The proposed strategy samples the flux leakage as the index both for occurrence and criterion for compensation of unbalanced magnetic force. The suggested method is designed such that there is no need to detect eccentricity fault direction, location, and type, which makes it cost effective and practical for a wide range of switched reluctance motors and applications. [ABSTRACT FROM PUBLISHER]

This paper presents a new method to increase the magnitude of impulse square wave of Pulse Forming Grid (PFN) and capability of producing the repetitive impulse waves by temporary converting it to Boost Converter (BC). For achieving to this goal the PFN inductors and capacitors are connected in series and parallel respectively using solid state switches and during this procedure the PFN impulse generator converts to BC and increases the voltage of capacitors uniformly to the considerable value. This technique causes to increase the discharging voltage level to the load many times more than its DC voltage source without using additional converter or transformer. The yielding results from numeric simulations in MATLAB prove this technique. [ABSTRACT FROM PUBLISHER]