- 标题
- 摘要
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- 实验方案
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - AC-DC Difference of a Thermal Transfer Standard Measured with a Pulse-Driven Josephson Voltage Standard
摘要： An upgraded pulse-driven AC Josephson voltage standard system at the National Research Council Canada allows the generation of quantum-accurate root-mean-square voltages up to 1 V at frequencies down to 10 Hz. The system is used to determine the AC-DC difference of a commercial thermal transfer standard, and an uncertainty budget is presented. Such quantum voltage systems could replace aging multi-junction thermal converters.
关键词： thermal converters,Josephson voltage standards,pulse-driven thermal transfer standards,Josephson arbitrary waveform synthesizers
更新于2025-09-10 09:29:36
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Low-Resolution Digital Pre-Compensation for High Speed Optical Links based on Dynamic Digital-to-Analog Conversion
摘要： Digital pre-compensation (DPC) is considered a promising technique for high throughput optical communication systems. The digital signal processing (DSP) at the transmitter relies on the availability of high-speed and high-resolution digital-to-analog devices to generate complex analog waveforms. However, one major challenge in current DACs technology is the limited resolution, which introduces dominant quantization distortions when extensive DSP is implemented. In this paper a dynamic quantization (DQ) approach is suggested, termed as digital-resolution-enhancer (DRE), which mitigates the quantization distortion effects. This approach is based on the underlying assumption that quantization is a non-linear deterministic operation, implying that its impact on transmission can be anticipated and minimized. The proposed method is theoretically and experimentally investigated with special focus on linear pre-compensation for bandwidth limited systems. Simulation results demonstrate that the DRE improves the signal-to-quantization-noise-ratio (SQNR) by up to 8dB. Thus, the DPC can be applied with reduced number of DAC’s bits. Conversely, the DRE can enable the use of more complex DPC schemes using the same DACs hardware, and consequently achieve extended reaches and higher transmission rates. Numerical simulations are verified by a set of extensive lab experiments. For electrical back-to-back (BTB) transmission, with an analog bandwidth of 13 GHz, 45 Gbaud QAM-64 is demonstrated using only 4 bits DACs. For optical BTB setup with an overall optoelectronic bandwidth of less than 5 GHz, 32 Gbaud QAM-4 is demonstrated using only 2.6 bits DACs.
关键词： Digital signal processing,digital-to-analog converters,quadrature amplitude modulation,coherent detection,digital pre-compensation
更新于2025-09-10 09:29:36
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Comparison of PNS and Thermal Converter AC Voltage Measurements Between BIPM and NMIA Using a Sampling Voltmeter
摘要： We present the results of an indirect comparison of low-frequency ac voltage measurements between a programmable Josephson voltage standard at BIPM, and thermal-converter-based ac-dc transfer standards at NMIA. The measurements were conducted at frequencies from 62.5 Hz to 625 Hz and voltages from 0.8 V to 7 V using two sampling digital voltmeters as transfer standards. The ac-dc difference of the transfer standards was chosen as a comparison quantity due to its independence of the long-term drift of the gain of the transfer standards. The results show that the relative agreement degrades linearly from 0.1×10-6 to 1×10-5 as the frequency increases from 62.5 Hz to 625 Hz. The metrological suitability of a sampling DVM used as a transfer standard is discussed.
关键词： thermal converters,AC signal measurements,transfer standard,programmable Josephson standard,sampling measurement techniques,differential sampling
更新于2025-09-10 09:29:36
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Supervision of a PV system with storage connected to the power line and design of a battery protection system
摘要： This work presents the supervision strategy in an Arduino card PV generator with storage connected to the low voltage grid. The studied system is composed of a photovoltaic generator, a boost converter, a buck-boost converter and a single-phase inverter. The power of the PV module depends on atmospheric conditions. Batteries are often confronted with overload problems and underload. The objective of this article is to manage the charging and discharging of the batteries, taking into account their protection against overload and under load and supervise the system. For this, supervision algorithms implemented in Arduino developed. Simulation results under Matlab show that the Arduino board has ensured the protection of the batteries and system supervision.
关键词： Arduino-card,Supervision,Statics converters,Photovoltaic
更新于2025-09-10 09:29:36
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[IEEE 2018 International Power Electronics Conference (IPEC-Niigata 2018 –ECCE Asia) - Niigata, Japan (2018.5.20-2018.5.24)] 2018 International Power Electronics Conference (IPEC-Niigata 2018 -ECCE Asia) - Optimized Bidirectional PFC Rectifiers & Inverters - Si vs. SiC vs. GaN in 2L and 3L Topologies -
摘要： In industrial drive systems, PFC converters are widely used. For PFC converters, a lot of different configurations and topologies exist and it is difficult to choose one. Therefore, in this paper, a comprehensive survey of possible configurations are optimized and compared against each other. The analysis shows the important aspects of the converter design and how the used semiconductor technology (Si, SiC and GaN) affects the total converter volume. A sensitivity analysis of certain power semiconductor parameters is performed to highlight the benefit of possible future developments of components and materials. In addition, the differences between the rectifier stage, where an EMI filter stage is necessary and the inverter stage, where the harmonic motor losses are influenced by the modulation scheme, are presented.
关键词： semiconductor technology,EMI filter,PFC converters,harmonic motor losses,modulation scheme
更新于2025-09-10 09:29:36
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[IEEE 2018 International conference on computation of power, energy, Information and Communication (ICCPEIC) - Chennai, India (2018.3.28-2018.3.29)] 2018 Internat2018 International Conference on Computation of Power, Energy, Information and Communication (ICCPEIC)ional conference on computation of power, energy, Information and Communication (ICCPEIC) - Analysis and Comparison of SEPIC, Landsman and Zeta Converters for PV Fed Induction Motor Drive Applications
摘要： Conventional Buck, Boost and Buck-Boost converters are not suitable for low and medium voltage Induction Motor (IM) drive applications. Moreover, these DC-DC converters not suitable for power factor correction, constant output voltage and to reduce harmonic distortion. In order to avoid drawbacks of basic DC-DC converters, three advanced DC-DC converters are studied in this article, namely, SEPIC, Zeta and Landsman converters. These converters work as Buck-Boost converters based on load requirement. The P&O MPPT technique is used to track the fast change of solar irradiances by the iterative process. Furthermore, it is used for the soft starting of squirrel cage induction motor. These converters output given to three-phase Voltage Source Inverter (VSI) to run the induction motor drive. The three converters operation is compared for IM drive applications by using MATAB Simulink software.
关键词： PV-module,IM drive,Landsman converters,SEPIC,Zeta converter,Three phase inverter
更新于2025-09-09 09:28:46
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[IEEE 2018 7th International Conference on Renewable Energy Research and Applications (ICRERA) - Paris, France (2018.10.14-2018.10.17)] 2018 7th International Conference on Renewable Energy Research and Applications (ICRERA) - Cooperative Control and Power Management for Islanded Residential Microgrids with Local Phase-wise Generation and Storage Units
摘要： A cooperative control and management strategy for islanded residential microgrids is presented in this paper. In addition to the loads, PV generation and battery storage are considered within each phase using droop control schemes. The proposed strategy uses a two-tiered management scheme to coordinate intra- and inter-phase power management. Each intra-phase control relies on a modi?ed vector control with a multi-segment (P/f) droop strategy to balance the generation, load and potential power transfer among other two phases. The inter-phase management only comes into play when there is an imbalance among phases so that desirable power can be transferred to the phases with de?ciencies. This is accomplished by back-to-back converters connecting the phases. PSCAD/EMTDC has been used to investigate the performance of the proposed strategy. It is interesting to observe that when extra power is needed in one particular phase, the desired amount is transferred through the back-to-back converters from other phases. As a result, the balance for voltage, frequency, and power can be achieved at both the phase level and the system level.
关键词： single-phase systems,Residential microgrids,back-to-back converters,power electronics,power management
更新于2025-09-04 15:30:14
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Quarter Video Graphics Array Digital Pixel Image Sensing With a Linear and Wide-Dynamic-Range Response by Using Pixel-Wise 3-D Integration
摘要： We have developed a quarter video graphics array (QVGA) digital pixel image sensor by using the 3-D integration technology. The pulse-frequency modulation (PFM) analog-to-digital converter (ADC) operates as a digital pixel, which overcomes the signal saturation due to the full well capacity of the photodiode (PD). We have also newly designed a PFM-ADC for pixels with a pinned PD and a floating diffusion to comply with the CMOS image sensor process used to attain high sensitivity and low noise. PDs, comparators, logic circuits, and counters are integrated into two silicon-on-insulator layers by pixel-wise 3-D integration with gold electrodes with a 5 μm diameter, thereby achieving a QVGA resolution for a 20-mm square chip in the 0.18- and 0.2-μm process nodes. The developed sensor exhibits both the excellent linearity and a wide-dynamic range of more than 96 dB. Video images with a high bit depth of 16 bit are also obtained to demonstrate the superior image sensing, capable of capturing the real world at high fidelity.
关键词： analog-to-digital converters (ADCs),dynamic range,image sensors,3-D integrated circuits,integrated circuit interconnections,pulse generation,silicon on insulator (SOI)
更新于2025-09-04 15:30:14