17 resultados para Pacific Coast (Asia)--Maps, Manuscript.
em Aston University Research Archive
Resumo:
A DSP implementation of Space Vector PWM (SVPWM) using constant V/Hz control for the open winding doubly-fed generator is proposed. This control of SVPWM modulation mode and open winding structure combination has the high voltage utilization ratio, greatly improves the control precision of the system, and reduces the stator winding output current distortion rate, though the complexity of the system is increased. This paper describes the basic principle of SVPWM and discusses the particularity of SVPWM waveform generated by hybrid vector under the condition of open winding. This method is applied to a state of doubly-fed wind power generator. The experimental verification shows that this control method can make the output voltage amplitude of the doubly-fed induction generator be 380V and the frequency be 50Hz by using of TMS32028335 chip based on constant V/Hz control of symmetric SVPWM modulation wave.
Resumo:
Due to high-speed rotation, the problems about rotor mechanics and dynamics for outer rotor high-speed machine are more serious than conventional ones, in view of above problems the mechanical and dynamics analysis for an outer rotor high-speed permanent magnet claw pole motor are carried out. The rotor stress analytical calculation model was derived, then the stress distribution is calculated by finite element method also, which is coincided with that calculated by analytical model. In addition, the stress distribution of outer rotor yoke and PMs considering centrifugal force and temperature effect has been calculated, some influence factors on rotor stress distribution have been analyzed such as pole-arc coefficient and speed. The rotor natural frequency and critical speed were calculated by vibration mode analysis, and its dynamics characteristics influenced by gyroscope effect were analyzed based on Campbell diagram. Based on the analysis results above an outer rotor permanent magnet high-speed claw pole motor is design and verified.
Resumo:
In this paper, a new open-winding control strategy is proposed for a brushless doubly-fed reluctance generator (BDFRG) applicable for wind turbines. The BDFRG control winding is fed via a dual two-level three-phase converter using a single dc bus. Direct power control based on maximum power point tracking with common mode voltage elimination is designed, which not only the active and reactive power is decoupled, but the reliability and redundancy are all improved greatly by increasing the switching modes of operation, while DC-link voltage and rating of power devices decreased by 50% comparing to the traditional three-level converter systems. Consequently its effectiveness is evaluated by simulation tests based on a 42-kW prototype generator.
Resumo:
A novel open-winding brushless doubly-fed generator (BDFG) system with two two-level bidirectional converters is proposed. This topology is equivalent to a three-level bidirectional converter connected to the typical BDFG, but solves the unbalanced-voltage-division problem of DC capacitor in the three-level converter, and has lower converter capacity, more flexible control mode, and better fault-tolerant ability. The direct power control (DPC) based on the twelve sections is adopted to implement the power tracking of the open-winding BDFG system, which is compared with the typical BDFG DPC system based on the six and twelve sections to verify the advantages of the proposed scheme.
Resumo:
This book presents an HRM scenario in a number of South-East Asian and Pacific Rim countries. It highlights the growth of the personnel/HR function, the dominant HRM system(s) in the area, the influence of different factors on HRM, and the challenges faced by HR functions in these nations. An excellent addition to this subject area, each chapter has been written by an area specialist. As the most topical and up-to-date book in its field, this outstanding book is suitable for both academics and practitioners in the field.
Resumo:
We use a smooth transition logistic function to test for equity market integration in a sample of Asia-Pacific countries. This allows us to gauge the speed at which a market is becoming integrated. Of the countries we examine we find that Thailand has the fastest pace of global integration. When we examine the extent to which local integration is taking place, we find that Singapore is experiencing the fastest rise in market integration. © 2004 Published by Elsevier Inc.
Resumo:
Editorial
Resumo:
This study investigates the impact of foreign direct investment (FDI) inflow and trade openness on the expansion of information and communication technologies (ICTs) for the period of 1996 to 2005, in the Asia-Pacific and Middle East regions. The results of regression analyses conducted indicate that while dissimilarities exist among the countries included in this study in terms of their level of socio-economic and political development, factors such as trade openness, education and the growth of GDP had a positive impact on their ICT development. While FDI inflow had positive impact on the expansion of ICTs on Asia-Pacific countries its impact on Middle Eastern countries was not statistically significant. The study results also show that governmental intervention in economic activities has a negative impact on ICT expansion in both regions. In the Middle East, regional conflict imposes additional negative impact on FDI inflow and trade openness and consequently, ICT expansion. The regression results show that those countries that implemented liberalization of their ICT sector were able to not only reduce the digital divide with other developed countries, but also increase their operations in both local and global markets.
Resumo:
This chapter investigates the impact of inward and outward FDI on ICT diffusion in the Asia-Pacific and Middle East regions for the period 1996-2008. The results indicate that while inward FDI has generally had a positive and significant impact on ICT diffusion in Asia-Pacific economies, its impact on the Middle Eastern countries has been detrimental. In contrast, the results of this study also show that outward FDI has had, in general, the inverse effect, it has been in general positive and significant for the Middle East countries but insignificant for Asia-Pacific economies.
Resumo:
This study investigates the impact of FDI and trade openness on ICT diffusion in the Asia-Pacific and Middle East regions from 1996-2005. The results indicate that while dissimilarities exist between the economies included in this study in terms of their level of socio-economic and political development, education and the growth of GDP have had a positive impact on ICT diffusion in both regions. However, while FDI has generally had a positive and significant impact on ICT diffusion in Asia-Pacific economies, its impact on Middle Eastern economies has been detrimental. The results of this study also show that trade-openness has had, in general, a positive and significant impact on ICT diffusion. Copyright © 2010, IGI Global.
Resumo:
Given the enormous economic and developmental changes being experienced by nations in the Asia-Pacific region, and the related movement of people between and across countries, it is critical that we better understand the HRM policies and practices of these nations. The latest instalment in the Global HRM series, Managing Human Resources in Asia-Pacific (2E) presents the HRM situations in a number of South-East Asian and Pacific Rim countries, highlighting the growth of the personnel and HR function, the dominant HRM system(s) in the area, the influence of different factors on HRM, and the challenges faced by HR functions in these nations. This edition extends its coverage to Cambodia, Fiji, Indonesia, and the Philippines; a new chapter discusses HR research challenges in the region, such as the transferability of western constructs, problems with data collection, and the emergence of MNEs from Asia Pacific. © 2014 Taylor & Francis.