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Ahmad M. Eid,Hyun Woo Lee,Mutsuo Nakaoka 전력전자학회 2006 JOURNAL OF POWER ELECTRONICS Vol.6 No.4
Various methods have been discussed to reduce detent force in a tubular permanent magnet type linear single phase AC generator. In particular, the proposed methods depend on variations of the permanent magnet construction. These methods include two approaches in the form of sloped magnets, and conical magnets in addition to the conventional method of optimizing the magnet length. The undesired detent force ripples were calculated by a two dimensional Finite Element Method (FEM). Moreover, the generated electromotive force in the stator coils was calculated for each configuration of the permanent magnet. The experimental results agreed well with those obtained from the FEM-based simulations. Sufficient reduction in the detent force was achieved over the range of 40% while the root mean square of the output voltage was maintained. It was found that sloping the permanent magnet decreased the detent force and at the same time increased the generated rms voltage of the AC generator. The performance of the designed linear AC generator was evaluated in terms of its efficiency, total weight, losses, and power to weight ratio.
Characterization and Performance Evaluation of Advanced Aircraft Electric Power Systems
Ahmad Eid,Hassan El-Kishky,Mazen Abdel-Salam,Mohamed T. El-Mohandes 전력전자학회 2010 JOURNAL OF POWER ELECTRONICS Vol.10 No.5
A model of an advanced aircraft electric power system is developed and studied under variable-speed constant-frequency (VSCF) operation. The frequency of the generator’s output voltage is varied from 400-㎐ to 800-㎐ for different loading scenarios. Power conversions are obtained using 12-pulse power converters. To reduce the harmonic contents of the generator output waveforms, two high-pass passive filters are designed and installed one at a time at the generator terminals. The performance of the two passive filters is compared according to their losses and effectiveness. The power quality characteristics of the studied VSCF aircraft electric power system are presented and the effectiveness of the proposed filter is demonstrated through compliance with the newly published aircraft electrical standards MIL-STD-704F.
Eid Ahmad M.,Lee Hyun-Woo,Nakaoka Mutsuo The Korean Institute of Power Electronics 2006 JOURNAL OF POWER ELECTRONICS Vol.6 No.4
Various methods have been discussed to reduce detent force in a tubular permanent magnet type linear single phase AC generator. In particular, the proposed methods depend on variations of the permanent magnet construction. These methods include two approaches in the form of sloped magnets, and conical magnets in addition to the conventional method of optimizing the magnet length. The undesired detent force ripples were calculated by a two dimensional Finite Element Method (FEM). Moreover, the generated electromotive force in the stator coils was calculated for each configuration of the permanent magnet. The experimental results agreed well with those obtained from the FEM-based simulations. Sufficient reduction in the detent force was achieved over the range of 40% while the root mean square of the output voltage was maintained. It was found that sloping the permanent magnet decreased the detent force and at the same time increased the generated rms voltage of the AC generator. The performance of the designed linear AC generator was evaluated in terms of its efficiency, total weight, losses, and power to weight ratio.
Efficient Linear Generator Design with Reduced Output Voltage Harmonics
Ahmad M. Eid,S. K. Kwon,Ki-Young Sub,Hyun Woo Lee,Mutsuo Nakaoka 전력전자학회 2005 전력전자학술대회 논문집 Vol.- No.-
Two-dimensional finite element method was used in the analysis to calculate the magnetic field parameters in a radial permanent magnet linear single-phase AC alternator. Both surface (SPM-LA) and internal permanent magnet (IPM-LA) prototype schemes are analyzed and compared according to three different parameters; the cogging force, the induced AC voltage and the THD of the induced AC voltage. Three different methods were used to reduce the THD of the induced voltage, tooth shoe, stepped tooth and chamfered tooth. It was found that the cogging force of the IPM-LA prototype scheme is always less than that of SPM-LA configuration due to the pole shoe. The stepped and chamfered tooth methods could achieve standard values for the THD of the induced voltage of the SPM-LA scheme. The cogging force was much reduced using the stator optimal length; for both schemes, as well as, the total alternator weight is reduced.
Characterization and Performance Evaluation of Advanced Aircraft Electric Power Systems
Eid, Ahmad,El-Kishky, Hassan,Abdel-Salam, Mazen,El-Mohandes, Mohamed T. The Korean Institute of Power Electronics 2010 JOURNAL OF POWER ELECTRONICS Vol.10 No.5
A model of an advanced aircraft electric power system is developed and studied under variable-speed constant-frequency (VSCF) operation. The frequency of the generator's output voltage is varied from 400-Hz to 800-Hz for different loading scenarios. Power conversions are obtained using 12-pulse power converters. To reduce the harmonic contents of the generator output waveforms, two high-pass passive filters are designed and installed one at a time at the generator terminals. The performance of the two passive filters is compared according to their losses and effectiveness. The power quality characteristics of the studied VSCF aircraft electric power system are presented and the effectiveness of the proposed filter is demonstrated through compliance with the newly published aircraft electrical standards MIL-STD-704F.
PERFORMANCE AND DESIGN OF A SINGLE-PHASE LINEAR SYNCHRONOUS GENERATOR USING FINITE ELEMENT METHOD
Ahmad M. Eid,김성준(Sung-Jun Kim),강주성(Ju-Sung Kang),이현우(Hyun-Woo Lee),Mutsuo Nakaoka 한국조명·전기설비학회 2005 한국조명·전기설비학회 학술대회논문집 Vol.2005 No.11월
This paper presents a general proposal to design and calculate the performance of a tubular permanent magnet linear generator treated here on the basis of the Finite Element Method. Optimizing the linear generator dimensions reduces the cogging force, which occurs due to the interaction between stator teeth and the permanent magnets. The generated AC voltage is analyzed and evaluated for both no load and load cases to take the armature reaction effects on the air gap flux density. A repetitive routine is followed to calculate the output AC voltage front the change of flux and tile speed of the single-phase linear generator. The AC output voltage is calculated for different resistive loads, and hence, tile linear generator load characteristic is obtained. The designed linear generator is capable to generate an output power of 5.3kW with AC output voltage of 222V with an efficiency of 96.8% at full load of 23.8A. The full load current is chosen based on the thermal properties of the coil wire Insulations.
Faizan Ahmad Khan,Eid Musallam Aljohani,Javid Ali 경남대학교 기초과학연구소 2022 Nonlinear Functional Analysis and Applications Vol.27 No.4
In this paper, we consider a class of random generalized nonlinear mixed variational inclusions with random fuzzy mappings and random relaxed cocoercive mappings inreal Hilbert spaces. We suggest and analyze an iterative algorithm for finding the approximate solution of this class of inclusions. Further, we discuss the convergence analysis ofthe iterative algorithm under some appropriate conditions. Our results can be viewed as a refinement and improvement of some known results in the literature.
Hisayuki Sugimura,Ahmad Eid,Hyun-Woo Lee,Mutsuo Nakaoka 전력전자학회 2005 전력전자학술대회 논문집 Vol.- No.-
In this paper, a constant frequency phase shifting PWM controlled voltage source full bridge-type series load resonant high-frequency inverter using the IGBT power modules is presented for innovative consumer electromagnetic induction heating applications such as a hot water producer, steamer and super heated steamer. The full bridge arm side link passive quasi-resonant capacitor snubbers in parallel with the each power semiconductor device and high frequency AC load side linked active edge inductive snubber-assisted series load resonant tank soft switching inverter with a constant frequency phase shifted PWM control scheme is discussed and evaluated on the basis of the simulation and experimental results. It is proved from a practical point of view that the series load resonant and edge resonant hybrid high-frequency soft switching PWM inverter topology, what is called class DE type, including the variable-power variable-frequency (VPVF) regulation function can expand zero voltage soft switching commutation range even under low output power setting ranges, which is more suitable and acceptable for induction heated dual packs fluid heater developed newly for consumer power utilizations. Furthermore, even in the lower output power regulation mode of this high-frequency load resonant tank high frequency inverter circuit it is verified that this inverter can achieve ZVS with the aid of the single auxiliary inductor snubber.