The Key Parameter Modeling of SiC MOSFET

2014 ◽  
Vol 986-987 ◽  
pp. 1391-1395
Author(s):  
Yong Long Peng ◽  
Rong Rong Li ◽  
Ya Bin Li
Keyword(s):  
Experimental Testing ◽  
Process Analysis ◽  
Variable Temperature ◽  
Voltage Source ◽  
Junction Capacitance ◽  
Internal Relations ◽  
Terminal Voltage ◽  
Change Of Variable ◽  
The Difference ◽  
Gate Resistance

This thesis mainly analysed the internal relations between parameters of SiC MOSFET and its dynamic and static characteristics respectively. And furthermore, a new method for modeling of SiC MOSFET based on PSpice was proposed in this paper. By introducing voltage’s controlling for voltage source E, we can compensate and correct the difference between PSpice default value of gate threshold voltage and actual value. At the same time, we can adopt two different junction capacitance models to describe the changes of junction capacitance which were brought about by the difference of the terminal voltage. In the meanwhile, there are newly increased source-drain resistance of MOSFET and gate resistance with the temperature change of variable temperature sub models. New models are able to fully and accurately reflect SiC MOSFET’s static and dynamic characteristics. Moreover, it provides an important foundation for switch process analysis of SC MOSFET, loss calculation and main circuit design. The fact that the experimental testing result is highly coincident with the simulation results verifies the correctness and accuracy of the models.

Correlation Between the V-I Characteristics of (0001) 4H-SiC PN Junctions Having Different Structural Features and Synchrotron X-ray Topography

2008 ◽  
Vol 1069 ◽  
Author(s):  
Ryoji Kosugi ◽  
Toyokazu Sakata ◽  
Yuuki Sakuma ◽  
Tsutomu Yatsuo ◽  
Hirofumi Matsuhata ◽  
...  
Keyword(s):  
High Energy ◽  
Structural Features ◽  
Incidence Geometry ◽  
Voltage Source ◽  
Large Area ◽  
Chip Area ◽  
Power Mosfets ◽  
X Ray ◽  
Pn Junctions ◽  
The Difference

ABSTRACTIn practical use of the SiC power MOSFETs, further reduction of the channel resistance, high stability under harsh environments, and also, high product yield of large area devices are indispensable. Pn diodes with large chip area have been already reported with high fabrication yield, however, there is few reports in terms of the power MOSFETs. To clarify the difference between the simple pn diodes and power MOSFETs, we have fabricated four pn-type junction TEGs having the different structural features. Those pn junctions are close to the similar structure of DIMOS (Double-implanted MOS) step-by-step from the simple pn diodes. We have surveyed the V-I characteristics dependence on each structural features over the 2inch wafer. Before their fabrication, we formed grid patterns with numbering over the 2inch wafer, then performed the synchrotron x-ray topography observation. This enables the direct comparison the electrical and spectrographic characteristics of each pn junctions with the fingerprints of defects.Four structural features from TypeA to TypeD are as follows. TypeA is the most simple structure as same as the standard pn diodes formed by Al+ ion implantation (I/I), except that the Al+ I/I condition conforms to that of the p-well I/I in the DIMOS. The JTE structure was used for the edge termination on all junctions. While the TypeA consists of one p-type region, TypeB and TypeC consists of a lot of p-wells. The difference of Type B and C is a difference of the oxide between the adjacent p-wells. The oxide of TypeB consists of the thick field oxide, while that of TypeC consists of the thermal oxide corresponding to the gate oxide in the DIMOS. In the TypeD structure, n+ region corresponding to the source in the DIMOS was added by the P+ I/I. The TypeD is the same structure of the DIMOS, except that the gate and source contacts are shorted. The V-I measurements of the pn junctions are performed using the KEITHLEY 237 voltage source meters with semi-auto probe machine. An active area of the fabricated pn junctions TEGs are 150um2 and 1mm2. Concentration and thickness of the drift layer are 1e16cm−3 and 10um, respectively.In order to compare the V-I characteristics of fabricated pn junctions with their defects information that obtained from x-ray topography measurements directly, the grid patterns are formed before the fabrication. The grid patterns were formed over the 2inch wafer by the SiC etching. The synchrotron x-ray topography measurements are carried out at the Beam-Line 15C in Photon-Factory in High-Energy-Accelerator-Research-Organization. Three diffraction conditions, g=11-28, -1-128, and 1-108, are chosen in grazing-incidence geometry (improved Berg-Barrett method).In the presentation, the V-I characteristics mapping on the 2inch wafer for each pn junctions, and the comparison of V-I characteristics with x-ray topography will be reported.

scholarly journals PRASANGKA: POTENSI PEMICU KONFLIK INTERNAL UMAT ISLAM

2013 ◽  
Vol 21 (1) ◽  
pp. 113
Author(s):  
Muhammad Alfandi
Keyword(s):  
Religious Conflict ◽  
The Other ◽  
Internal Conflict ◽  
Religious Groups ◽  
Internal Relations ◽  
Nahdlatul Ulama ◽  
Way Of Thinking ◽  
The Difference ◽  
The Way ◽  
Islamic Organizations

<p class="IIABSBARU">This study is about the potential prejudice sparked internal conflict of Muslims, especially between the group Nahdlatul Ulama (NU) and the Council of Tafsir Al-Qur'an (MTA) in Surakarta. Lately there is a conflict between NU and the MTA congregation. MTA is questioned by NU in some areas because of the materials and methods of preaching/dakwah considered to be provocative and less likely to appreciate the difference fiqhiyah and abusive deeds done by NU. From the reason above, the conflict between these two Islamic organizations appeared. One of the triggers that caused the internal conflict among Muslims is the certain group of Muslims can not understand well the other religious groups, which have different ideological backgrounds; that it affects the way of thinking, behaving and acting that are different from themselves. As a result, the internal relations marred by religious conflict, caused by the internal religious prejudice. Similarly, the possibility that occurred among the group of NU and MTA.</p><p class="IKa-ABSTRAK">***</p>Penelitian ini adalah tentang potensi memicu prasangka konflik internal umat Islam, terutama antara kelompok Nahdlatul Ulama (NU) dan Majelis Tafsir Al-Qur'an (MTA) di Surakarta. Akhir-akhir ini ada konflik antara NU dan jemaat MTA. MTA dipertanyakan/diperdebatkan oleh NU di beberapa daerah karena bahan dan metode dakwah/dakwah dianggap/cenderung provokatif dan cenderung tidak menghargai perbedaan <em>fiqhiyah</em> dengan perbuatan kasar yang dilakukan oleh NU. Dari alasan di atas, konflik antara kedua organisasi Islam telah terjadi/ muncul. Salah satu pemicu yang menyebabkan konflik internal di kalangan umat Islam adalah kelompok tertentu umat Islam tidak bisa memahami dengan baik kelompok agama lain, yang memiliki latar belakang ideologi yang berbeda, se­hingga mempengaruhi cara berpikir, bersikap dan bertindak yang berbeda dari diri mereka sendiri. Akibatnya, hubungan internal yang dirusak oleh konflik agama, disebabkan oleh prasangka keagamaan internal. Demikian pula, ke­mungkin­an yang terjadi di antara kelompok NU dan MTA.

scholarly journals Lyapunov Function Based Flux and Speed Observer Using Advanced Non-linear Backstepping DVC for PWM-Rectifier Connected Wind-turbine-driven PM Generator

2021 ◽  
Author(s):  
Youcef Saidi ◽  
Abdelkader Mezouar ◽  
Yahia Miloud ◽  
Mohammed Amine Benmahdjoub ◽  
Brahim Brahmi ◽  
...  
Keyword(s):  
Lyapunov Function ◽  
Pulse Width Modulation ◽  
Control Policy ◽  
Synchronous Generator ◽  
Voltage Source ◽  
System Control ◽  
Speed Sensor ◽  
Non Linear ◽  
The Difference ◽  
Stator Flux

In this paper, modeling, and speed/position sensor-less designed Direct Voltage Control (DVC) approach based on the Lyapunov function are studied for three-phase voltage source Space Vector Pulse Width Modulation (SVPWM) Rectifier Connected to a Permanent Magnet Synchronous Generator (PMSG) Variable Speed Wind Power Generation System (VS-WPGS). This control strategy is based on voltage orientation technique without mechanical speed sensor. Advanced Non-linear Integral Backstepping Control (IBSC) of the Generator Side Converter (GSC) has the ability to have a good regulation of the DC link voltage to meet the requirements necessary to achieve optimal system operation, regardless of the disturbances caused by the characteristics of the drive train or some changes into the DC load. The estimation of the speed is based on Model Reference Adaptive System (MRAS) method. This method consists in developing two models one of reference and the other adjustable for the estimation of the two d-q axis components of the stator flux from the measurement of currents, the speed estimated is obtained by canceling the difference between the reference stator flux and the adjustable one using Lyapunov criterion of hyper-stability. Some results of simulation using Matlab/Simulink® are presented, discussed to prove the efficiency and robustness of the system control policy for WPGS against external and internal perturbations.

scholarly journals A Control Strategy for Suppressing Zero-Sequence Circulating Current in Paralleled Three-Phase Voltage-Source PWM Converters

2020 ◽  
Vol 10 (5) ◽  
pp. 1703 ◽  
Author(s):  
Zhao Han ◽  
Xiaoli Wang ◽  
Baochen Jiang ◽  
Jingru Chen
Keyword(s):  
Control Strategy ◽  
Voltage Source ◽  
Duty Ratio ◽  
Phase Voltage ◽  
Pwm Converters ◽  
Circulating Current ◽  
Three Phase ◽  
Zero Sequence ◽  
The Difference ◽  
Zero Vector

In microgrids, paralleled converters can increase the system capacity and conversion efficiency but also generate zero-sequence circulating current, which will distort the AC-side current and increase power losses. Studies have shown that, for two paralleled three-phase voltage-source pulse width modulation (PWM) converters with common DC bus controlled by space vector PWM, the zero-sequence circulating current is mainly related to the difference of the zero-sequence duty ratio between the converters. Therefore, based on the traditional control ideal of zero-vector action time adjustment, this paper proposes a zero-sequence circulating current suppression strategy using proportional–integral quasi-resonant control and feedforward compensation control. Firstly, the dual-loop decoupled control was utilized in a single converter. Then, in order to reduce the amplitude and main harmonic components of the circulating current, a zero-vector duty ratio adjusting factor was initially generated by a proportional–integral quasi-resonant controller. Finally, to eliminate the difference of zero-sequence duty ratio between the converters, the adjusting factor was corrected by a feedforward compensation link. The simulation mode of Matlab/Simulink was constructed for the paralleled converters based on the proposed control strategy. The results verify that this strategy can effectively suppress the zero-sequence circulating current and improve power quality.

scholarly journals Voltage Sources in 2D Fourier-Based Analytical Models of Electric Machines

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Bert Hannon ◽  
Peter Sergeant ◽  
Luc Dupré
Keyword(s):  
Finite Element ◽  
Great Majority ◽  
Element Model ◽  
Electric Machines ◽  
Analytical Models ◽  
Voltage Source ◽  
Pulse Width Modulated ◽  
Simulation Tools ◽  
Drive Trains ◽  
Terminal Voltage

The importance of extensive optimizations during the design of electric machines entails a need for fast and accurate simulation tools. For that reason, Fourier-based analytical models have gained a lot of popularity. The problem, however, is that these models typically require a current density as input. This is in contrast with the fact that the great majority of modern drive trains are powered with the help of a pulse-width modulated voltage-source inverter. To overcome that mismatch, this paper presents a coupling of classical Fourier-based models with the equation for the terminal voltage of an electric machine, a technique that is well known in finite-element modeling but has not yet been translated to Fourier-based analytical models. Both a very general discussion of the technique and a specific example are discussed. The presented work is validated with the help of a finite-element model. A very good accuracy is obtained.

Process Analysis for Rapid Tooling Technology Based on Rapid Prototyping

2011 ◽  
Vol 216 ◽  
pp. 798-803 ◽  
Author(s):  
Hong Pu Liu ◽  
Jun Su ◽  
Xiao Jing Li
Keyword(s):  
Rapid Prototyping ◽  
Process Analysis ◽  
Rapid Tooling ◽  
Production Cycle ◽  
Fabrication Cost ◽  
Modeling Process ◽  
Working Principle ◽  
The Difference ◽  
Tooling Technology

This paper discussed the working principle, classification, modeling process and technology features for rapid tooling based on rapid prototyping and investigated into the difference between rapid tooling with traditional modeling manufacture. Several typical rapid tooling technologies are compared and summarized from mould period, fabrication cost and production cycle. Some key problems that rapid tooling industry will face with are analyzed. The application of the rapid tooling based on rapid prototyping is prospected.

scholarly journals Electronic interactions in 1D-π-assemblies from TLS analysis of thermal motion

2014 ◽  
Vol 70 (a1) ◽  
pp. C659-C659
Author(s):  
Sergey Lindeman ◽  
Marat Talipov ◽  
Shriya Wadumethrige ◽  
Oleg Dolomanov ◽  
Rajendra Rathore
Keyword(s):  
Charge Transfer ◽  
Graphical Representation ◽  
Electronic Materials ◽  
Variable Temperature ◽  
Supramolecular Assemblies ◽  
Thermal Motion ◽  
Theoretical Interpretation ◽  
Electronic Shell ◽  
Donor Acceptor ◽  
The Difference

Advanced features of TLS analysis within Olex2 program package allow for a detailed analysis of electronic redistribution in supramolecular systems. Particularly, the possibility of calculating TLS tensors in user-defined coordinate systems along with qualitative graphical representation of difference thermal motion are especially useful for analysis of atomic asphericity and intra- and inter-molecular electron redistribution. In addition, these features allow for a directional dynamic analysis of intermolecular motions from variable-temperature experiments. We explored the exciting new possibilities analyzing supramolecular assemblies closely resembling modern electronic materials for a series of electron donor-acceptor complexes and ion-radical salts based on aromatic octamethyl-anthracene and anti-aromatic octamethyl-biphenylene substrates. The difference TLS analysis revealed intimate details of chemical bond polarization and electronic shell expansion for acceptor components along with electronic shell contraction for donor components of the complexes indicative of intra- and intermolecular charge transfer. Also, the variable-temperature analysis of relative thermal motion of the complex components in the crystals revealed some widening of the potential-energy minima in direction of the electronic overlap as a result of intermolecular pi-orbital coupling both in charge-transfer and charge-resonance supramolecular assemblies. A theoretical interpretation of the observed peculiarities was undertaken supported by respective spectroscopic data.

Interval Estimation and Hypothesis Testing

2014 ◽  
Vol 543-547 ◽  
pp. 1717-1720
Author(s):  
Da Yang
Keyword(s):  
Hypothesis Testing ◽  
Statistical Inference ◽  
Mutual Influence ◽  
Hypothesis Test ◽  
Interval Estimation ◽  
Point Of View ◽  
Economic Management ◽  
Engineering Technology ◽  
Internal Relations ◽  
The Difference

Mathematical statistics is a branch of mathematics has extensive application of interval estimation and hypothesis testing, which are two important problems of statistical inference. As two important statistical inference methods, interval estimation and hypothesis testing problem is more and more widely used in the field of economic management, finance and insurance, scientific research, engineering technology, the science of decision functions are recognized by more and more people. Can go further to establish mutual influence and communication between the interval estimation and hypothesis testing, can use the theory to explain the problem of interval estimation of parameter hypothesis test, this is an important problem to improve the statistical inference theory. Therefore, the basis on the internal relations between the interval estimation and hypothesis test for deep research, explain the problem of hypothesis testing and interval estimation from the point of view, discusses the difference and connection between the two.

Energetic materials: variable-temperature crystal structures of γ- and ∊-HNIW polymorphs

2004 ◽  
Vol 37 (5) ◽  
pp. 808-814 ◽  
Author(s):  
Nadezhda B. Bolotina ◽  
Michaele J. Hardie ◽  
Richard L. Speer Jr ◽  
A. Alan Pinkerton
Keyword(s):  
Thermal Expansion ◽  
Energetic Materials ◽  
Variable Temperature ◽  
Mean Field ◽  
Field Potential ◽  
Atomic Displacement ◽  
Linear Temperature Dependence ◽  
Linear Temperature ◽  
The Difference ◽  
Atomic Displacement Parameters

Crystals of γ- and ∊-hexanitrohexaazaisowurtzitane (γ- and ∊-HNIW, space groupP21/nfor both crystals) have been investigated in the 100–298 K temperature range using single-crystal X-ray diffraction techniques. Temperature-dependent changes of their crystal lattices have been evaluated from the second-rank thermal expansion tensors. Both lattices undergo anisotropic thermal expansion, that of γ-HNIW being more anisotropic than that of the ∊ phase. Comparison with previously reported predictions from molecular dynamics calculations indicates significant differences. Although there are many short (less than van der Waals) intermolecular interactions in both polymorphs, there is no obvious relationship between the short distances and the difference in thermal expansion behavior. Non-linear temperature dependence of the atomic displacement parameters is indicative of anharmonicity of the crystal mean field potential.

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