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关键词： 压滤机   皮带   一体化   自动控制  

摘要： 通过将单一的电动机保护控制方式改为变频器控制装置,达到对皮带电机的保护及调速目的,实现压滤机皮带一体化的自动控制,减小皮带的损耗,提高系统的自动化程度。

关键词： 绝缘栅双极晶体管   功率元件   安森美   IGBT   内部人士   微控制器   半导体   市场动态  

摘要： 最近,海外大厂安森美、英飞凌等纷纷传出IGBT订单接不过来的消息。安森美深圳厂内部人士透露消息称,车用绝缘栅双极晶体管订单(IGBT)已满且不再接单,但不排除订单中存在一定比例的超额下单。士兰微和华润微相关人士也表示,由于汽车和光伏需求增加明显,IGBT订单增长很快,做不过来。供应链业者表示,2021年起车用半导体中的功率元件、微控制器最为缺乏,且直至2022年情况都未见明显改善。在IGBT产品中,车用IGBT的缺口则更大。CINNOResearch半导体事业部总经理Elvis称,车规级IGBT更下探至0.5,即供需缺口在50%以上。

关键词： Circuit faults   Inverters   Insulated gate bipolar transistors   Support vector machines   Predictive models   Fault diagnosis   Transforms   CC   EEMD   IGBT   Inverter   Machine Learning   Open-circuit fault   RMS   Spectral envelope  

摘要： The principal objective of this paper is to detect and automatically monitor switch open-circuit faults in a two-level three-phase voltage source inverter fed induction motor from the processing of its current signals. The proposed diagnostic method uses both signal processing techniques and machine learning techniques in order to detect and localize the switch under an open-circuit fault. First, the Hilbert-Huang transform using the empirical ensemble mode decomposition is employed for each phase current signal, which leads to extracting the intrinsic mode functions. In order to optimally choose the function indicating the open-circuit fault harmonic, two factors, namely, the root mean square and the correlation coefficient are calculated out for each function. In this regard, two criteria are proposed that lead to choose the optimal function giving better information about the defected phase. The spectral envelope of the optimal function permits extra0cting the fault harmonic of the switch. Second, different machine learning techniques are applied to locate and classify the switch open-circuit faults with the hyper-parameters optimization for a better design of the different models. Finally, a comparative study of the different machine learning techniques is carried out for determining the best classifier for the open-circuit faults. The experimental results effectively demonstrate a very high classification rate of 98.98%.

关键词： Thermal resistance   Surface morphology   Surface roughness   Surface resistance   Rough surfaces   Contact resistance   Temperature measurement   Power cycling   press-pack insulated-gate bipolar transistor (PP-IGBT)   surface roughness   thermal contact resistance  

摘要： In this article, the correlation between the thermal contact resistance and the surface roughness characteristics of the contact interface in the press-pack insulated-gate bipolar transistor (PP-IGBT) modules during power cycling was studied by experimental measurements and finite-element (FE) simulation-based factorial design analysis. Thermal transient test technology was applied to examine the change in the thermal characteristic parameters of the PP-IGBT module. This shows that the increase in the thermal contact resistance of the Al metallization/emitter Mo contact interface occurs more dramatically during power cycling. A 3-D surface profilometer was used to evaluate the surface morphology parameters of the Al metallization/emitter Mo contact interface. The equivalent root-mean-square (RMS) roughness increases during power cycling, and the equivalent asperity slope and the equivalent spacing between asperities increase slightly. Additionally, the surface roughening in the corner area of the chip is more obvious than in other regions. A fractional factorial design analysis based on FE simulations was performed. The results indicate that the thermal contact resistance strongly depends on the main effects of the real contact area and the spacing between the asperities, and the RMS roughness and the asperity slope interaction.

关键词： Insulated gate bipolar transistors   Heating systems   Heat transfer   Junctions   Finite element analysis   Temperature measurement   Multichip modules   Cauer model   heat propagation path   insulated-gate bipolar transistors (IGBTs)   temperature-dependent thermal parameters  

摘要： In pursuit of high power density and high reliability of power converters, the junction temperature of power devices becomes an essential indicator for heath condition monitoring and thermal management. Particularly under high-temperature operating conditions, the temperature-dependent thermal properties of the chip and ceramic materials must be incorporated to enhance the prediction accuracy. In this article, an improved temperature-dependent Cauer-type thermal network of insulated-gate bipolar transistor (IGBT) module is established. The temperature dependence of thermal parameters for the chip layer and ceramic layer is meticulously considered. More importantly, finite-element method (FEM) simulation is used to yield the heat flux curve of the power module at the center line in order to better imitate the real heat-spreading scenario. In this way, the effective heat transfer area of each layer can be calculated accurately and analytically. By this analytic method, the temperature-dependent thermal impedance can be efficiently determined. Compared with prior-art fully FEM-based temperature-dependent thermal impedance characterization method, the method proposed in this article reduces the FEM simulation time cost approximately 20 times under the same computing hardware facilities and considerably simplifies the parameter extraction process. Finally, experimental results based on two commercial IGBT modules successfully validate the usefulness, effectiveness, and accuracy of the proposed thermal network model.

关键词： 直流换流站  

ISBN: (纸本)9787030707291

摘要： 本书围绕换流阀关键部件老化失效与可靠性评测问题，以换流阀关键部件失效模拟与可靠性评估为主线，从关键部件多物理场建模、失效模拟、换流阀系统可靠性评估、模型验证和评估软件等方面开展研究，阐述了计及关键部件失效模拟的换流阀模组可靠性及其评测。

关键词： Insulated gate bipolar transistors   Capacitance   Switches   Voltage   Transient analysis   Topology   MOSFET   Flyback   insulated gate bipolar transistor (IGBT)   mechanism model   pulse voltage   switching transient  

摘要： With the rapid development of semiconductor devices, researchers have proposed different types of high-frequency pulse voltage generators based on power electronic converters to meet the requirements of microorganism inactivation, water pollution purification, and piezoelectric and dielectric electroactive polymer drives. The transient modeling of these high-voltage converters aids in understanding the electrical characteristics of the devices and optimizing their performances. This article analyzes the electrical behavior of a semiconductor switching device (i.e., an insulated gate bipolar transistor) used during the switching transient of the converter and constructs an electromagnetic transient model of the flyback converter that considers both the parasitic elements and the ferromagnetic losses of the transformer. The accuracy of the proposed model is then verified by comparing calculation results obtained using the model with experimental measurement results.

关键词： Wires   Bonding   Insulated gate bipolar transistors   Metallization   Layout   Stress   Resistance   Electro-thermal coupling   Fourier series   multitier layout   physics-based IGBT model   stitch-bonding wire   three-dimensional (3-D) multicellular equivalent circuit   wire layout optimization  

摘要： The stitch wire configuration is widely adopted for large-area IGBT chips. However, an inhomogeneous wire current density introduces uneven self-heating and nonuniform chip heating, which exacerbates the chip thermal stress. In this article, a multicellular electro-thermal model considering the stitch-bonding wires is derived to optimize the wire layout parameters. Furthermore, the current density alleviation of wire bonds is investigated to be the most sensitive and effective method to comprehensively mitigate the thermal nonequilibrium and local overheating. Consequently, an improved multitier layout is proposed to further achieve thermal stress suppression without any additional components and advanced materials. Finally, a triple-tier-bonded IGBT module with optimal design parameters is fabricated to validate the thermal mitigation performance. The prototype experimental results demonstrate that the modeling error is less than 3.0%. The multitier layout decreases the current density by 57.6%, hence, the maximum and average chip temperature are reduced by 21.8% and 12.4%, respectively.

关键词： IGBT   MATLAB/Simulink   SPMC   SPWM  

摘要： This paper presents a multi-input, multi-output power converter system using a single-phase matrix converter (SPMC) circuit topology. In particular, this technology is of vital importance in floating production such as offshore oil and gas platforms where space is crucial, therefore requiring a reduction in equipment size and weight. The proposed circuit topology only employed a single circuit to perform energy conversion of direct current (DC) to alternating current (AC), DC to DC, AC to DC, and AC to AC operations, thus can reduce the power losses resulting in high power density. As a result, it can promise technological advancement and convergence, hence, support the manufacturing sector transition to industry 4.0, and in line with the United Nation’s sustainable development goals. The proposed converter model will be validated in terms of electrical circuit operations through the computer simulation (MATLAB/Simulink) software. © 2022, Institute of Advanced Engineering and Science. All rights reserved.

关键词： carbon nanotube   current stability   IGBT   X-ray source   current stability  

摘要： The cold cathode X-ray source has potential application in the field of radiotherapy, which requires a stable dose. In this study, a gated carbon nanotube cold cathode electron gun with high current stability was developed by using Insulated Gate Bipolar Transistor (IGBT) modulation, and its application in X-ray source was explored. Carbon nanotube (CNTs) films were prepared directly on stainless steel substrate by chemical vapor deposition and assembled with control gate and focus electrodes to form an electron gun. A maximum cathode current of 200 mu A and approximately 53% transmission rate was achieved. An IGBT was used to modulate and stabilize the cathode current. High stable cathode current with fluctuation less than 0.5% has been obtained for 50 min continuous operation. The electron gun was used in a transmission target X-ray source and a stable X-ray dose rate was obtained. Our study demonstrates the feasibility of achieving high current stability from a gated carbon nanotube cold cathode electron source using IGBT modulation for X-ray source application.