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Abstract: The Permanent magnet synchronous motor (PMSM) drive has emerged as one of the most preferred motor drives for industrial applications. Its distinguished advantages include high torque density, high efficiency, and vast speed range operation. This paper presents, First, details of PMSM drives and their components. Second, explain the modelling of PMSM. Third, discuss the needs of position sensors, their applications, and their performance with the required accuracy. They are finally concerned about extensive industrial applications and future sensorless and sensor-based PMSM drives research trends. Conclusion This paper reviews permanent magnet synchronous motor types and Permanent magnet materials used its advantage and disadvantage and the classification of PM rotor type. This paper briefly discusses the position sensor, its types, and application based on requirements. Based on comparative analysis of permanent magnet materials, briefly discuss sensors and classification of permanent magnet motor, recommendations are given on their practical application.

The PV system is in demand as it converts the solar energy directly into electricity. For obtaining desired output various conversion stages are adopted. This paper deals with the open loop analysis of PV array, boost converter and inverter. By applying gate pulse to the inverter by Interleaved discontinuous PWM technique via flip flop the performance of the inverter has been improved. MATLAB/Simulink based result of the PV array and converters is presented and also the THD analysis of inverter is done. The single stage conversion has disadvantage that more number of PV cells are required for greater power generation and also control is difficult. But this paper involves the two stage conversion which overcomes these disadvantages as first of all the value of voltage is boost up via boost converter and passes through the inverter for power generation. In this paper by applying LC filter the value of THD has been reduced to 0.44%.

Performance and analysis of the bridge and bridgeless type of power factor improvement method of boost converter has been presented in this paper. Conventional type of converter has higher switching and conduction losses, low power factor, high THD, and less efficiency. A bridgeless Boost converter with PFC improves power quality and has higher efficiency than other traditional, bridge boost PFC converter. Passive filters used in a bridgeless PFC boost rectifier help in reducing THD and increasing a Power factor at the source. Complete analysis of Boost full-bridge converter is done in this paper. Bridgeless type of PFC boost converter has low line current flows from source to load, one semiconductor device, improving efficiency and reduces losses in comparison to the conventional bridge type of boost converter. MATLAB simulation result has been presented which indicate that Power Factor is nearer to unity.

Power converter devices interfaces the grid with RESs which injects the harmonic current in the system. Hence, this paper presents different controlling schemes for inverters used in the grid. Phase-shifting control of single-phase inverter has been shown in this paper which provides power control injecting to the grid. $3-\varphi$ inverter control involves dq control, $\alpha\beta$ control, and abc control. The use of voltage (reactive) and frequency (active) control scheme provides mitigation of voltage harmonics. Various scheme for controlling Multi-Functional Grid-connected inverter involves double loop dq control on the basis of discrete Fast Fourier Transform and Phase Lock Loop method is used which helps in coordination of active (frequency) and reactive (voltage) power control. Various controlling method for Z-source inverter has been presented which helps in improvement of the quality of power of the distribution system.

Solid-state Buck-Boost AC-DC converters involve the isolation of high-frequency transformer which develops in Buck-Boost configuration with the improved power quality. Input current with reduced total harmonic distortion (THD), at the supply side in AC mains provides power factor correction. Isolated DC output voltage is fed to high power rating loads. It is represented by the study of improved power quality of different types of buck-boost converters with high-frequency isolation, classification of buck-boost converters with high-frequency isolation, control strategies, components selections and design consideration of buck-boost converter, simulation study, results and discussion, comparison of power density & cost, selection criteria, latest trends, future developments, and potential applications are described. THD analysis has been described in this paper.

The semiconducting property of passive films formed on Alloy 1 (18Cr-2Mo-1N)], Alloy 2 (17.5Cr-3Mo-0.5N)] and Alloy 3 (Type 316 SS) were studied by using the Mott-Schottky (M-S) approach in 3.5 wt. % NaCl solution of pH 2, 7 and 12. The M-S analysis shows that the film acts as n - type and p - type semiconductors across the potential range. The donor density of Alloy 1 has been found to be lower by about 31 %, 11 % and 6 % as compared to that of Alloy 2 at pH 2, 7 and 12 respectively. However; Alloy 3 has higher donor density 44 %, 27 % and 30 % in comparison with Alloy 1. The donor density of Alloy 3 found to be greater about 21 %, 18 % and 25 % to the Alloy 2 at pH 2, 7 and 12 respectively. These results indicate that the sensitivity of electrolyte composition and the presence of alloying elements like nitrogen and nickel on the donor density of passive film. High nitrogen stainless steels exhibited a lower donor density that corresponds to good protectiveness, more stable passive film which is in agreement with a low passive current density (ipass), higher pitting potential (Epit) and polarization resistance (Rp).

An ideal high performance poly(etheretherketone) (PEEK)/AlN composite that has unique combination of anisotropic linear coefficient of thermal expansion (CTE) and dielectric properties was developed for the use in electronic packaging substrate as an alternative of conventionally used epoxy/E-glass substrate. The out-of-plane and in-plane CTEs of the composites were very close to that of copper and silicon chip, respectively. The dielectric constants of the composites are almost independent with increasing frequency. The dissipation factor decreased approximately 50% compared to the pure PEEK. These results reveal that the composite may be the futuristic candidate for high performance electronic packaging substrate.

The morphology, thermal, mechanical, and dielectric properties of high-performance poly(etheretherketone)/Si(3)N(4) nanocomposites fabricated by hot pressing were investigated. It was found that the coefficient of thermal expansion (CTE) and dissipation factor decreased significantly with increasing Si(3)N(4) content, whereas thermal stability was affected slightly. A nanocomposite with 30 wt% Si(3)N(4) exhibited about 45% and 23% decrease in CTE, below and above T(g), respectively. The glass-transition temperature (T(g)) was increased up to 20 degrees C. Microhardness was improved by 20% at 10 wt% Si(3)N(4) content and thereafter it improved slightly. Modified rule of mixture with beta = 0.1 or Halpin-Tsai model with xi = 4 fits well the microhardness. The dielectric constant and loss factor of the nanocomposites are quite low, and thermal stability is much higher compared with commercial products. Various models were also used to correlate CTE and dielectric constant. POLYM. ENG. SCI., 51:509-517, 2011. (C) 2010 Society of Plastics Engineers

The crystallization, morphology, microhardness, scratch hardness, dynamic modulus, and wear behavior of high performance poly(ether-ether-ketone) (PEEK) matrix nanocomposites reinforced with 0 to 30 wt % silicon nitride (Si3N4) nanoparticles were reported. The crystallinity of PEEK nanocomposites increases at 2.5 wt % Si3N4 but, thereafter it decreases with increasing Si3N4 content due to the hindrance to the ordering of PEEK chains. The crystallization peak temperature and crystallization onset temperature increases by 14°C for 10 wt % nanocomposite. The melting temperature does not vary significantly with Si3N4 content. SEM shows almost uniform distribution of Si3N4 in the PEEK matrix. The Vickers microhardness and scratch hardness increases significantly up to 10 wt % Si3N4 content.The dynamic modulus of nanocomposites increases below and above Tg of PEEK. The specific wear rate of nanocomposites with 2.5 wt % Si3N4 is reduced significantly and it is lowest at 10 wt % Si3N4. However, the coefficient of friction of nanocomposites is more than that of pure PEEK. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The wear and friction properties of poly (ether-ether-ketone) (PEEK) reinforced with 0–33 vol % (60 wt %) micron size Al2O3 composites were evaluated at a sliding speed of 1.0 m/s and nominal pressure from 0.5 to 1.25 MPa under dry sliding conditions using a pin-on-disk wear tester. The wear resistance of the pure PEEK is 10-fold higher than that of mild steel under the similar test condition. It is improved to 18-fold as compared with mild steel at 3.5 vol % Al2O3 content. The improvement in wear properties may be attributed to the thin, tenacious, and coherent transfer film formed between the steel countersurface and composite pin. However, the wear resistance of PEEK containing above 3.5 vol % Al2O3 was deteriorated, despite their higher hardness and stiffness as compared with that of composites containing lower Al2O3 content. This is attributed to the formation of thick and noncoherent transfer film, which does not prevent the wear of the composites from hard asperities of countersurface. Moreover, hard Al2O3 particles present in transfer film act as third body wear mechanism. The coefficient of friction of the composites is higher than that of pure PEEK. SEM and optical microscopy have shown that wear of pure PEEK occurs by the mechanism of adhesion mainly whereas of PEEK composites by microploughing and abrasion. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Microhardness of high performance PEEK matrix composites reinforced with micro- and nanosize ceramic particles of aluminum nitride and alumina was evaluated with Vickers hardness tester. The microhardness of composites increases with increasing ceramic particle loading. The microhardness of PEEK/AlN composites is higher than that of PEEK/Al2O3 composites. For a given volume fraction, the improvement in microhardness of nanocomposites is higher than that of microcomposites. For the first time, the Halpin–Tsai equation was applied to correlate the microhardness. It was found that the adjustable parameter, i.e. ξ, is different for both particles. The value of ξ is higher for nanocomposites compared to microcomposites, © Elsevier

High performance polymer matrix composites based on poly(ether–ether–ketone) (PEEK) as matrix and aluminum nitride particle (AlNp) as filler were prepared. The effect of AlNp on the storage modulus, loss modulus, mechanical loss factor, and glass transition were investigated. The AlNp reinforcement is more pronounced above glass transition temperature (Tg). Composite containing 70 wt.% AlNp exhibit about 100% increase in storage modulus at 50 °C and about 500% increase at 250 °C, and 19 °C increase in glass transition temperature as compared to pure PEEK. Peak height of tan δ for composites was decreased to one sixth of the pure PEEK. It is probably due to improved crystallinity of PEEK and strong interaction between the AlNp and PEEK matrix. SEM reveals excellent distribution of AlNp in PEEK matrix and good interaction between AlNp and PEEK matrix., © Elsevier

This paper deals with anisotropic behavior of thermal expansivity (α) of poly(ether-ether-ketone) (PEEK) sample prepared by compression molding above the melting point of polymer. The α was determined using thermo mechanical analyzer (TMA) for the temperature interval 50–250 °C in expansion mode. It is found that out-of-plane thermal expansivity (αz) is 3.8-fold of the in-plane thermal expansivity (αxy) below the glass transition temperature (Tg) of PEEK while αz is decreased to 1.8-fold of the αxy above the Tg. Moreover, the average αz over the range studied is about 2.2-fold of the αxy. This anisotropic behavior may be attributed to the alignment of polymer spherulites and chains along in-plane direction due to compressive forces under hot compression molding., © Elsevier

Novel high performance aluminum nitride (AlN)/poly(ether-ether-ketone) (PEEK) composites containing 0-50 wt.% fractions of AlN were prepared by solution blending method followed by hot pressing to evaluate their density, melting temperature, crystallization, thermal stability, morphological behavior and Vickers hardness by using different characterization techniques. Differential scanning calorimetry results indicated that the AlN particles are very effective nucleating agent, which results in increase in melting point, hot crystallization temperature and crystallinity of composites as the AlN content increases. Thermogravimetric analysis showed enhanced thermal stability of the composites with respect to PEEK. Density and X-ray diffraction techniques showed that crystallinity of the composites increases as the wt.% of AlN content increases in polymer matrix. Scanning electron microscopy revealed that AlN particles were well dispersed with no porosity in composites. Vickers hardness of the samples increased from 24 kg/mm(2) for the pure PEEK to 35 kg/mm(2) for AlN/PEEK composites. (c) 2005 Elsevier Ltd.

The effects of Al2O3 additions on the compaction and sintering behaviour of a leadborosilicate glass (LG) have been investigated. LG powder was prepared by melting, fritting and milling a glass of the composition: 77PbO, 10B2O3, 10SiO2, 2Al2O3 and 1P2O5 (wt.%). The mean particle sizes of the powders were: LG, 6.5 μm and Al2O3, 3.3 μm. The compaction behaviour of LG–Al2O3 powder mixtures can be represented by a new compaction equation: [(Dg−D0)/(1−D0)]=(P/Pf)n, where Dg is the relative green density, D0 the relative tap density and n and Pf are material constants. The exponent n decreases from 0.192 to 0.065 as the Al2O3 content is increased from 0 to 100 vol.%. The Frenkel equation for isothermal shrinkage has been found to be valid. It is shown that in the glass matrix composites the minimum sintering temperature can be determined by measuring the dilatometric deformation temperature. The presence of Al2O3 in excess of 15 vol.% has been found to strongly retard the sintering kinetics. An addition of 45 vol.% Al2O3 increases the activation energy for sintering from 67 to 112 kcal mol−1. The presence of Al2O3 particles also induced a partial crystallisation in LG matrix.

The tribological properties of poly(ether–ether–ketone) (PEEK)/aluminum nitride (AlN) composites reinforced with micro- and nano-AlN particles were evaluated under dry sliding conditions. The wear resistance of pure PEEK is 10-fold higher than mild steel. It was further improved by 2-fold at 20 wt % micro-AlN and by more than 4-fold at 30 wt % nano-AlN composite compared with pure PEEK. The improvement in wear resistance was attributed to a thin and coherent transfer film. However, it was deteriorated on further increasing micro-AlN. The coefficient of friction of the composites was increased. Scanning electron microscopy and optical microscopy of worn surfaces and transfer films have been explained in detail. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The thermal, mechanical, and dielectric properties of new high-performance polyphenylene sulfide/aluminum nitride (AlN) composites prepared by hot pressing were investigated for use in electronic packaging. The coefficient of thermal expansion was decreased by 41%. The glass-transition temperature and Vickers microhardness were increased by 13A degrees C and 46%, respectively, for the 15.1 vol.% AlN composite. A modified rule of mixtures with beta of 0.065 fits the data. The dielectric constant and loss factor of the composites are within the range of requirements for commercial use.

High-performance printed circuit board or electronic packaging substrate with low warping particularly at high frequency is the key demand of manufacturers. In the present work, poly(etheretherketone) (PEEK) matrix composites reinforced with untreated micron size aluminum nitride (AlN) and alumina (Al(2)O(3)) particles have been studied for dynamic modulus in the temperature range varying from 30 to 250 degrees C. At 48 vol % particles, the room temperature modulus of the PEEK/AlN composites increased by approximately fivefold (similar to 23 GPa), whereas it increased by twofold for PEEK/Al(2)O(3) composite. The reinforcing efficiency is more pronounced at higher temperatures. The significant improvement in modulus was attributed to the better adhesion between the matrix and the AlN particles. Scanning electron microscope (SEM) and Kubat parameter showed that the poor adhesion between the matrix and the Al(2)O(3) particles resulted in comparatively smaller increase in modulus of PEEK/Al(2)O(3), despite higher intrinsic modulus of Al(2)O(3) than that of AlN. SEM showed almost uniform distribution of particles in the matrix. The experimental data were correlated with several theoretical models. The Halpin-Tsai model with xi (xi) is equal to four correlates well up to 48 vol % AlN composites while xi is equal to two correlates only up to 18 vol % Al(2)O(3) composites. Guth-Smallwood model also correlates well up to 28 vol % AlN and 18 vol % Al(2)O(3)-filled composites. Thereafter, data deviated from it due to the particles tendency to aggregate formation. (c) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 436-444, 2011

Metalorganic vapor phase epitaxy has been used for the first time to grow epitaxial GaAs layers on (111) and (100) oriented Si either using CaF2 or stacked (Ca,Sr)F2/CaF2 as a buffer. The GaAs layers show sharp and well resolved electron channeling patterns. The Rutherford backscattering (RBS) ion channeling minimum yield is 5% for (111) orientation and 6% for (100) orientation. The GaAs(111) layers are untwinned. The strain in the GaAs layer has been measured with RBS and X-ray diffraction and it is found that the thermal mismatch-induced strain in the GaAs layer is considerably lower than in similar GaAs films grown without flouride buffer.

The mechanical, thermal, and dielectric properties of novel high performance poly(ether-ether-ketone) (PEEK)/AIN nanocomposites were discussed. The stiffness of the nanocomposites was significantly improved in the glassy state as well as rubbery state. The coefficient of thermal expansion (CTE) of the nanocomposites was found substantially lower than that of pure PEEK. The glass transition temperature and melting temperature of the nanocomposites were increased significantly. The thermal stability and dielectric constant of the nanocomposites were increased slightly with AIN content. The significant improvement in the properties of the nanocomposites was attributed to the good adhesion between the AIN nanoparticles and the polymer matrix. The fabricated nanocomposite is very promising for use in electronics packaging substrate as an alternative substrate owing to its good thermal, mechanical and dielectric properties.

Modified Al (7010) matrix composites with 0-15 wt.% dispersion;; of SiC particles (∼7 μm) have been developed by powder metallurgy route. The processing route involved attritor milling of Al, Zn, Mg, Cu and SiC powders blended with 2% stearic acid to accomplish mechanical alloying and dispersion of SiC. The process of mechanical alloying was monitored by image analysis and XRD. It was found that mechanical alloying to the extent of 50-75% was achieved in 12 hours of attritor milling. With the help of DSC the hot pressing condition (565°C under 110 MPa for 2 minutes) was fixed in such a way that it led to completion of the remaining alloying of the constituent elements and also high densification (porosity < 1%). The particulate strengthening by SiC has been found to be quite effective in increasing the Brinell hardness (134 to 191 kg/mm2) and in retaining a high tensile strength at 300°C.

The thermal expansion behaviour of high performance poly(ether-ether-ketone) (PEEK) composites reinforced with micro-(8 mu m) and nano- (39 nm) sized Al(2)O(3) particles was studied. The distribution of Al(2)O(3) in the PEEK matrix was studied by scanning electron microscopy and transmission electron microscopy. The coefficient of thermal expansion (CTE) was reduced from 58 x 10(-6) degrees C(-1) for pure PEEK to 22 x 10(-6) degrees C(-1) at 43 vol% micro-Al(2)O(3) and to 23 x 10(-6) degrees C(-1) at 12 vol% nano-Al(2)O(3) composites. For a given volume fraction, nano- Al(2)O(3) particles are more effective in reducing the CTE of composites than that of micro-Al(2)O(3) particles. This may be attributed to the much higher interfacial area or volume of nanocomposites than that of microcomposites. The upper limit and lower limit of the Schapery model separately fit closely the CTE of the micro- and nano-composites, respectively. Other models such as the rule of mixture and Kerner and Turner models were also correlated with the data.

High performance nanocomposites were prepared by incorporating 0–12 vol.% nano-sized (39 nm) Al2O3 particles into PEEK matrix using compression molding. The microhardness and dynamic mechanical properties of the nanocomposites increase with increasing Al2O3 content. The wear resistance of the nanocomposites evaluated at a sliding speed of 1.0 m/s and nominal pressure from 0.5 MPa to 1.25 MPa under dry sliding conditions was improved more than threefold at 0.8 vol.% Al2O3 content. However, the wear resistance of the nanocomposites containing above 1.67 vol.% Al2O3 was deteriorated, despite their higher hardness and stiffness as compared to that of nanocomposites containing lower Al2O3 content. The surface roughness of the wear track formed over the countersurface increases with increasing Al2O3 content. The coefficient of friction of nanocomposites was higher than that of pure PEEK. SEM and optical microscopy have shown that wear of pure PEEK occurs by the mechanism of adhesion mainly, whereas of nanocomposites by microploughing and abrasion. Energy dispersive spectrometry (EDS) shows that Fe and alloying elements of countersurface transfer to the wear debris at higher Al2O3 content., © Elsevier

The dynamic mechanical properties of high-performance polymer matrix composites based on semicrystalline poly(ether ether ketone) (PEEK) and aluminum oxide (Al2O3) were evaluated in the temperature range of 30–250°C with a three-point-bending mode at a frequency of 1 Hz. The storage modulus and loss modulus changed significantly with the variation of the Al2O3 content in the PEEK matrix. The Al2O3 reinforcement was more pronounced above the glass-transition temperature (Tg). A composite containing 60 wt % (33 vol %) Al2O3 exhibited about a 78% increase in the storage modulus at 50°C and about a 200% increase at 200°C. However, there was no significant change in the mechanical loss factor and Tg associated with the peak of the mechanical loss factor or loss modulus with the addition of Al2O3. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 568–575, 2007

This paper deals with the preparation and characterization of nanocomposites of poly(ether ether ketone) (PEEK) containing nano-aluminum oxide (n-Al2O3) filler up to 30 wt% (12 vol%) loading. Nanocomposites showed improved thermal stability, crystallization, and coefficient of thermal expansion (CTE). Thermogravimetric analysis showed enhanced thermal stability and char yield on increasing the n-Al2O3 loading in PEEK matrix. The peak crystallization temperature is increased up to 13 °C for the nanocomposites as compared to pure PEEK. The CTE is decreased to a value very close to the CTE of copper at 12 vol% Al2O3 loading. The CTE values obtained were compared with the theoretical equations in the literature. The X-ray diffraction showed that PEEK crystalline structure is unchanged with addition of n-Al2O3. The distribution of n-Al2O3 in the PEEK matrix was studied by transmission electron microscopy and scanning electron microscopy. The results show that the prepared n-Al2O3/PEEK nanocomposites may have potential applications in electronics., © Elsevier

A model for investigating the dynamic behaviour of solar cells, which allows the simulation of the measurements process with flash solar simulators, is presented in this paper. This model is then applied to the simulation of measurement processes currently employed by common solar simulator types. It is shown that the cell capacitance, the series resistance and cell area can all influence the measurements, giving rise to transient errors, especially in short flash solar simulators. It is also shown that point distribution as well as scan time also have significant importance.