Search

Your search keyword '"Chen, Zhongyuan"' showing total 28 results
Start Over Author "Chen, Zhongyuan" Publisher ieee
28 results on '"Chen, Zhongyuan"'

7. Internal pressure distributions of press-pack IGBT modules under two contact methods

Author

Guanbin Wu, Lei Zhang, Chen Zhongyuan, Lin Zhongkang, Jinyuan Li, and Zhang Xizi

Subjects
Materials science, Machining, Spring (device), Process (computing), Internal pressure, Mechanical engineering, Insulated-gate bipolar transistor, Chip, Displacement (vector), Finite element method
Abstract

Pressure contact methods of press-pack IGBT include rigid contact and compliant contact. The rigid contact structure is supported by rigid copper electrode for each chip module, and the compliant contact structure is supported by disc spring assemble for each chip module. In this paper, the finite element mechanical models of IGBT sub-modules in rigid and compliant contact were established, and the pressure distribution rules of the chips under different height tolerances and uneven forces on the modules were analyzed. The experimental tests on IGBT samples using two kinds of contact methods were carried out by mechanical press and FUJI prescale films, and the correctness of the FEM simulation results was verified. By comparison, it is found that the use of disc springs will compensate for the displacement deviations caused by the machining errors, thereby automatically adjusting the pressure distributions on surfaces of chips. The parameters of the disc springs are more easily controlled than the machining errors of the various components, thus the requirements for the packaging process can be reduced.

Published
2019

8. Research on the Current Distribution Characteristics within a Single Chip of press pack IGBT

Author

Jinyuan Li, Pan Yan, Zhang Xizi, and Chen Zhongyuan

Subjects
Single chip, Materials science, Current distribution, business.industry, 020208 electrical & electronic engineering, Electrical engineering, 02 engineering and technology, Insulated-gate bipolar transistor, 021001 nanoscience & nanotechnology, Chip, Connection (mathematics), Contact surfaces, 0202 electrical engineering, electronic engineering, information engineering, Current (fluid), Electric current, 0210 nano-technology, business
Abstract

At present, the researches on high-power IGBT devices mainly solve the problems of uniformities of electric currents, temperatures, and stresses between different chips caused by multi-chip parallel connection. However, there are few studies on the uniformity of the current distribution within a single chip and its influencing factors. This paper analyzes the current distributions within the press pack IGBT chips from four aspects: different contact surfaces between the chip and molybdenum sheet, different on-resistances of the cells, different temperature distributions, and different pressure distributions. This study provided technical guidance for the design of press pack IGBT chips and devices.

Published
2018

15. Improved Access Control Based on Analytic Hierarchy Process

Author

Zheng, Chengfeng, primary, Long, Sijie, additional, Liu, Jingyi, additional, Wu, Canliu, additional, Qi, Tianyi, additional, Zhu, Yongsheng, additional, Li, Xiaojie, additional, Xie, Zefeng, additional, Shuai, Jia, additional, Chen, Zhongyuan, additional, and Jiang, Wei, additional

Published
2018
Full Text
View/download PDF

21. Impact of Positive Affectivity on Employees' Organizational Identification: A Structural Equation Modeling Approach

Author

Wei Jun and Chen Zhongyuan

Subjects
Positive affectivity, Beijing, Organizational identification, Prestige, Sample (statistics), Organizational commitment, Psychology, Social psychology, Structural equation modeling
Abstract

This paper explores the impact of positive affectivity on organizational identification. Using a sample of 480 employees from Beijing, Guangzhou and Jiangsu, the researchers examined the dynamic relationships among organizational prestige, organizational identification and positive affectivity. Results of structural equation modeling revealed that the hypothesized model with organizational prestige as a predictor and positive affectivity as a mediator between organizational prestige and organizational identification fit better than alternative models.

Published
2008

28. Collocation Accuracy of Visuo-Haptic System: Metrics and Calibration.

Author

Wang, Dangxiao, Zhang, Yuru, Zhou, Wanlin, Zhao, Hui, and Chen, Zhongyuan

Abstract

Human resolution of collocation error between haptic and stereoscopic displays influences the design of visuo-haptic rendering algorithms, yet it is not well characterized. In the present study, we propose quantified metrics to measure the visuo-haptic collocation error and a prototype based on half-silvered mirror is established to validate the metrics. After defining collocation error in terms of the spatial correspondence between a tool and a surface, a mathematical model is derived that relates collocation error to the visual and haptic rendering modules within the computational pipeline. A calibration method consisting of Perspective Calibration (PC) and Model Calibration (MC) is then proposed to compensate for manufacturing and assembly tolerances. Based on measurement values by a precise measurement apparatus, i.e., the FARO Arm, parameters for the PC and MC were determined. System performance is evaluated by measuring the collocation error between a real handle and its visual avatar. The average collocation error was 1.8 mm within the XwYwOw plane, and the error never exceeded 7 mm within an 80 mm\times80 mm\times80 mm workspace. [ABSTRACT FROM PUBLISHER]

Published
2011
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results