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991.
A single-switch parallel resonant converter for induction heating is implemented. The circuit consists of an input LC-filter, a bridge rectifier, and a controlled power switch. The switch operates in soft commutation mode and serves as a high frequency generator. The output power is controlled via the switching frequency. A steady state analysis of the converter operation is presented. A closed-loop circuit model is also presented, and the experimental results are compared with the simulation results. 相似文献
992.
Moon-Sik Lee 《ETRI Journal》2009,31(3):321-323
A wideband beamforming algorithm for estimating the azimuth angle, elevation angle, velocity, and range using a planar phased radar array with antenna switching is proposed. It uses the time-variant steering vector model. Simulation results illustrating the performance of the proposed beamformer are presented. 相似文献
993.
As industrial technology gets more mature, a single fiber can offer more and more wavelengths. However, it also results in
a large amount of switching ports at optical cross-connects (OXCs). Certainly, it is expected that higher and higher complexity
is inevitable to control and manage such large OXCs. In this paper, we study the dynamic wavelength assignment problem in
waveband switching (WBS) networks composed of multi-granular OXCs (MG-OXCs). Moreover, in order to relax the wavelength continuity
constraint on lightpath establishments, each MG-OXC node is equipped with a certain number of converters. To efficiently minimize
the extra port consumption and utilize wavelength converters, we proposed an online wavelength assignment algorithm named
Least Weighted Configuration Cost (LWCC). For a new request, LWCC first adopts fixed routing and then exploits the layered-graph approach and a new cost function
for edge weight assignment to determine adequate wavelength(s). The performance metrics of interest include both blocking
performance and converter utilization. Numerical results show that LWCC is superior in waveband grouping and therefore results
in significant performance gain in terms of blocking probability.
相似文献
Ching-Fang HsuEmail: |
994.
995.
J. M. Martínez H. Amarís J. Sanz 《Electrical Engineering (Archiv fur Elektrotechnik)》2006,88(5):403-409
The use of conventional low voltage induction motors fed by pulse width modulated (PWM) inverters has begun to present important problems. These waveforms consist of steep-fronted pulses having very short rise times (about 100 ns in modern IGBT bridges) and high frequency repetition rates (up to 20 kHz) whose immediate consequences are additional electrical stresses in an induction motors insulation system. In this paper a frequency domain model for the analysis and characterization of the internal voltage distribution in random wound coils is presented. The model allows voltage prediction in time domain when an inverse fast Fourier transform (FFT) transformation is performed, and requires only a few frequency domain impedance measurements. This methodology will be useful for accurately predicting the voltage distribution in motor windings during the design stage, and reducing the risk of premature failure in motor insulation. Experimental and theoretical results are presented and compared and model effectiveness using different approximations is studied. 相似文献
996.
997.
针对现有配电系统的切换方式及其存在的问题,介绍了一种新型无扰动配电装置,对其性能、工作原理进行分析,对该装置的几种切换方式进行了比较,并结合现有配电系统的工作特点,探讨了无扰动配电装置在实际应用中的前景。 相似文献
998.
999.
随着现代高速数字电路的快速发展,同步开关噪声(SSN)问题变得越来越突出。该文提出了一种适用于高速数字电路中抑制同步开关噪声的新型宽带平面电磁带隙(EBG)结构,并用Ansoft HFSS软件对该电磁带隙结构进行数据仿真分析。仿真结果表明,在抑制深度为-30dB时,其阻带范围为0.2~5.6 GHz,与传统的L-bridge型电磁带隙结构比较,阻带下限截止频率下降了500 MHz,阻带带宽增加了1.4GHz,相对带宽增加了38.1%,且能全向抑制同步开关噪声。 相似文献
1000.
《Optical Fiber Technology》2014,20(3):184-189
A wavelength routing device based on only one N × N cyclic arrayed waveguide grating (AWG) having easy extended channels configuration is presented in this paper. It is easy to extend the dense wavelength division multiplexing (DWDM) channel configuration through this wavelength routing device. According to the cyclic wavelength of AWG, the wavelength routing devices are easy to configure more than N extended DWDM channels through cascading more proper tunable fiber Bragg gratings (FBGs). With only one 8 × 8 AWG, two different wavelength routing structures were built to evaluate static crosstalk and the bit-error-rate (BER). Three of the 16 inputted DWDM channels were demonstrated to verify that the proposed wavelength routing device, with only one 8 × 8 AWG, could configure extended DWDM channels without interfering with other channels. The results show that the wavelength routing device can produces a better performance and offers a cheaper way to extend the DWDM channel configuration for a dynamic network. 相似文献