Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 84

年份

2023 9

2022 6

2021 9

2020 5

2019 5

2018 1

2017 3

2016 1

2015 4

2014 2

2013 6

2012 7

2010 2

2009 2

2008 5

2007 5

2006 3

2005 2

2004 2

2002 2

展开︾

关键词

肠道菌群 2

AQAM 1

Matlab仿真 1

PTCNN 1

PWM 1

VO₂薄膜 1

Windows'95 1

Z箍缩 1

β-粒子的横向振动 1

中华自然理念 1

中国聚变工程实验堆 1

中子测量 1

临床价值 1

二极管箝位型逆变器 1

云降水微物理参数 1

人员疏散 1

仅1吸收 1

介导机制 1

伪码 1

展开︾

检索范围：

排序：展示方式：

Frequency-controlable sine signal based on PWM and its implementation on FPGA

Lianzhen HUANG, Jiangang LI, Dongjun ZHANG

《机械工程前沿（英文）》 2012年第7卷第3期页码 322-328 doi: 10.1007/s11465-012-0312-9

摘要：

A sine generation method that the different frequent sine signals can be generated by the different Pulse-Width Modulation (PWM) signals generated by Field-Programmable Gate Array (FPGA) through low-pass filter of fixed parameters was proposed. The method just takes a few FPGA resources and was proved feasible by the theory. The experiment results and theory analysis tally.

关键词： Pulse-Width Modulation (PWM) Field-Programmable Gate Array (FPGA) frequency controllable

HTML PDF 收藏

Simulation of grid connection and maximum power point tracking control of brushless doubly-fed generator in wind power system

Hicham SERHOUD, Djilani BENATTOUS

《能源前沿（英文）》 2013年第7卷第3期页码 380-387 doi: 10.1007/s11708-013-0252-z

摘要： In this paper, based on the analysis of the mathematical model in a common synchronous reference frame of the brushless doubly-fed generator (BDFG), the grid connection strategy and maximum energy extraction control were both analyzed. Besides, the transient simulation of no-load model and generation model of the BDFG have been developed on the MATLAB/Simulink platform. The test results during cutting-in grid confirmed the good dynamic performance of grid synchronization and effective power control approach for the BDFG-based variable speed wind turbines.

关键词： brushless doubly-fed generator (BDFG) modeling grid connection control back-to-back pulse-width modulation (PWM) converter wind power generation

HTML PDF 收藏

Toward a nonlinear control of an AC-DC-PWM converter dedicated to induction heating

Amel HADRI-HAMIDA, S. ZEROUALI, A. ALLAG

《能源前沿（英文）》 2013年第7卷第2期页码 140-145 doi: 10.1007/s11708-013-0243-0

摘要： In this paper, a nonlinear control strategy applied to an AC-DC-pulse width modulation (PWM) converter is developed and simulated. First a nonlinear system modeling is derived with state variables of the input current and the output voltage by using power balance of the input and output. The system is linearized and decoupled, and then a state feedback law is obtained. For robust control of parameter perturbation, integrators are added to the exact feedback control law. The simulation is provided to verify the validity of the control algorithm.

关键词： DC-DC converter AC-DC-pulse width modulation (PWM) converter induction heating nonlinear control

HTML PDF 收藏

DFIG sliding mode control fed by back-to-back PWM converter with DC-link voltage control for variable

Youcef BEKAKRA,Djilani BEN ATTOUS

《能源前沿（英文）》 2014年第8卷第3期页码 345-354 doi: 10.1007/s11708-014-0330-x

摘要： This paper proposes an indirect power control of doubly fed induction generator (DFIG) with the rotor connected to the electric grid through a back-to-back pulse width modulation (PWM) converter for variable speed wind power generation. Appropriate state space model of the DFIG is deduced. An original control strategy based on a variable structure control theory, also called sliding mode control, is applied to achieve the control of the active and reactive power exchanged between the stator of the DFIG and the grid. A proportional-integral-(PI) controller is used to keep the DC-link voltage constant for a back-to-back PWM converter. Simulations are conducted for validation of the digital controller operation using Matlab/Simulink software.

关键词： doubly fed induction generator (DFIG) wind turbine back-to-back pulse width modulation (PWM) DC-link voltage sliding mode control

HTML PDF 收藏

低调制度下二极管箝位型多电平逆变器新型PWM控制方法

辛想,张庆范,胡顺全,李瑞来

《中国工程科学》 2007年第9卷第10期页码 91-96

摘要：

二极管箝位型多电平逆变器作为一种应用于高压大功率变换场合的变换器，其PWM控制技术是研究的核心内容之一。本文针对已有载波PWM方法中低调制度下电平退化的问题，提出了一种新颖的载波PWM方法，既便是在低调制度下，所有的电平都能够得到应用。

关键词：二极管箝位型逆变器载波PWM 低调制度冗余状态

HTML PDF 收藏

A driving pulse edge modulation technique and its complex programming logic devices implementation

Xiao CHEN,Dong-chang QU,Yong GUO,Guo-zhu CHEN

《信息与电子工程前沿（英文）》 2015年第16卷第12期页码 1088-1098 doi: 10.1631/FITEE.1500111

摘要： With the continual increase in switching speed and rating of power semiconductors, the switching voltage spike becomes a serious problem. This paper describes a new technique of driving pulse edge modulation for insulated gate bipolar transistors (IGBTs). By modulating the density and width of the pulse trains, without regulating the hardware circuit, the slope of the gate driving voltage is controlled to change the switching speed. This technique is used in the driving circuit based on complex programmable logic devices (CPLDs), and the switching voltage spike of IGBTs can be restrained through software, which is easier and more flexible to adjust. Experimental results demonstrate the effectiveness and practicability of the proposed method.

关键词： Driving pulse edge modulation Switching voltage spike Complex programmable logic device (CPLD) Active gate drive

HTML PDF 收藏

Power quality investigation of a solar PV transformer-less grid- connected system fed DVR

Akhil GUPTA,Saurabh CHANANA,Tilak THAKUR

《能源前沿（英文）》 2014年第8卷第2期页码 240-253 doi: 10.1007/s11708-014-0322-x

摘要： This paper presents a single stage transformer-less grid-connected solar photovoltaic (PV) system with an active and reactive power control. In the absence of active input power, the grid-tied voltage source converter (VSC) is operated in a reactive power generation mode, which powers the control circuitry, and maintains a regulated DC voltage to the VSC. A data-based maximum power point tracking (MPPT) control scheme which performs power quality control at a maximum power by reducing the total harmonic distortion (THD) in grid injected current as per IEEE-519/1547 standards is implemented. A proportional-integral (PI) controller based dynamic voltage restorer (DVR) control scheme is implemented which controls the grid side converter during single-phase to ground fault. The analysis includes the grid current THD along with the corresponding variation of the active and reactive power during the fault condition. The MPPT tracks the actual variable DC link voltage while deriving the maximum power from the solar PV array, and maintains the DC link voltage constant by changing the modulation index of the VSC. Simulation results using Matlab/Simulink are presented to demonstrate the feasibility and validations of the proposed novel MPPT and DVR control systems under different environmental conditions.

关键词： data-based maximum power point tracking (MPPT) total harmonic distortion (THD) proportional integral control voltage restorer pulse width modulation

HTML PDF 收藏

Fault tolerant control strategy for modular PWM current source inverter

《能源前沿（英文）》 2023年第17卷第2期页码 228-238 doi: 10.1007/s11708-022-0852-6

摘要： In this paper, a fault-tolerant control method for an input-series output-parallel modular grid-tied pulse-width modulation (PWM) current source inverter is proposed to address the most commonly seen single symmetrical gate-commutated thyristor (SGCT) open-circuit fault problems. This method actively offsets the neutral point of the current space vector to ensure a sinusoidal output of the grid current, and it can achieve the upper limit power of the inverter under the condition of a single SGCT open-circuit fault. In addition, an active damping control method based on grid harmonic current feedback is proposed after analyzing the influence of the transformer ferromagnetic resonance caused by the neutral point offset on the power quality of the grid current. It has been demonstrated that the proposed method effectively suppresses the resonance caused by the transformer and the modified modulation, improving the grid current’s power quality.

关键词： current source converter (CSC) fault-tolerant control space vector modulation active damping resonance suppression power quality

HTML PDF 收藏

Analysis and design of pulse frequency modulation dielectric barrier discharge for low power applications

Tang-tang GUO,Xing-liang LIU,Shi-qiang HAO,Chi ZHANG,Xiang-ning HE

《信息与电子工程前沿（英文）》 2015年第16卷第3期页码 249-258 doi: 10.1631/FITEE.1400185

摘要： For low power dielectric barrier discharge (DBD) used in small-size material treatment or portable devices, highstep transformer parasitic capacitance greatly influences the performance of the resonant converter as it is of the same order of magnitude as the equivalent capacitance of DBD load. In this paper, steady-state analysis of the low power DBD is presented, considering the inevitable parasitic capacitance of the high-step transformer. The rectifier-compensated first harmonic approximation (RCFHA) is applied to linearize the equivalent load circuit of DBD at low frequency and the derived expressions are accurate and convenient for the analysis and design of the power supply. Based on the proposed linear equivalent load circuit, the influence of transformer parasitic capacitance on the key parameters, including the frequency range and the applied electrode voltage, is discussed when the power is regulated with pulse frequency modulation (PFM). Also, a design procedure is presented based on the derived expressions. A prototype is constructed according to the design results and the accuracy of the design is verified by experimental results.

关键词： Dielectric barrier discharge Rectifier-compensated first harmonic approximation Parasitic capacitance Power converter design

HTML PDF 收藏

同步发电机励磁系统中PWM控制的仿真研究

贾贵玺,徐伟,郭宝钥,张臣堂

《中国工程科学》 2005年第7卷第6期页码 50-53

摘要：同步发电机励磁系统采用了PWM整流技术，实现励磁电流低谐波和励磁功率单元高功率因数转换，提高了发电机供电质量，并用MATLAB对设计系统做出仿真验证，证明该设计对改善发电机输出电压、提高功率单元电能利用率有明显效果

关键词： PWM 高功率因数励磁系统 Matlab仿真

HTML PDF 收藏

Esophageal pulse oximetry is more accurate and detects hypoxemia earlier than conventional pulse oximetry

null

《医学前沿（英文）》 2012年第6卷第4期页码 406-410 doi: 10.1007/s11684-012-0217-3

摘要：

The esophagus is perfused directly by prominent arteries and may provide a more consistent tissue source for pulse oximetry. The goal of this study was to evaluate the sensitivity and accuracy of an esophageal pulse oximetry probe on patients during controlled hypoxemia in comparison to measurements obtained with conventional pulse oximetry (SpulseO₂). Forty-five ASA I–II adult patients were included in this prospective observational study. Nellcor digital oximetric probes were placed on finger tips for SpulseO₂ before anesthesia. After tracheal intubation, an esophageal probe was placed in the lower segment of the esophagus for esophageal oximetric monitoring (SoesO₂). All patients were disconnected from the breathing circuit to establish a controlled hypoxemia, and were re-connected to the breathing circuit and ventilated with 100% oxygen immediately when SoesO₂ dropped to 90%. Matched SoesO₂ and SpulseO₂ readings were recorded when SoesO₂measurements were at 100%, 95%, 90% and the lowest reading. The time for SoesO₂ and SpulseO₂ to drop from 100% to 95%, 90% and return to 100% was recorded. Oxygen saturation from arterial blood samples (SartO₂) was also measured at each time point respectively. The linear correlation coefficient of the regression analysis between SartO₂ and SoesO₂ was 0.954. The mean±2SD of the difference was 0.3%±4.3% for SoesO₂vs. SartO₂ and 6.8%±5.6% for SpulseO₂vs. SartO₂ (P<0.001). The 95% confidence interval for the absolute difference between SoesO₂ and SartO₂ was 0.3% to 0.7% and 6.2% to 7.4% between SpulseO₂ and SartO₂. The time to reach 90% saturation measured with SoesO₂ was approximately 94 seconds earlier than the SpulseO₂ (P<0.001). In conclusion, SoesO₂ is more accurate and enables earlier detection of hypoxemia when compared to conventional pulse oximetry during hypoxemia for patients undergoing general anesthesia.

关键词： esophageal pulse oximetry conventional pulse oximetry hypoxemia

HTML PDF 收藏

Calculation methods of the crack width and deformation for concrete beams with high-strength steel bars

Jianmin ZHOU, Shuo CHEN, Yang CHEN

《结构与土木工程前沿（英文）》 2013年第7卷第3期页码 316-324 doi: 10.1007/s11709-013-0211-0

摘要： Three groups of concrete beams reinforced with high-strength steel bars were tested, and the crack width and deformation of the specimens were observed and studied. To facilitate the predictions, two simplified formulations according to a theory developed by the first author were proposed. The advantages of the formulations were verified by the test data and compared with several formulas in different codes.

关键词： concrete beam high-strength steel bar crack width deformation

HTML PDF 收藏

Influence of nozzle height to width ratio on ignition and NO

Liutao SUN, Yonghong YAN, Rui SUN, Zhengkang PENG, Chunli XING, Jiangquan WU

《能源前沿（英文）》 2021年第15卷第2期页码 431-448 doi: 10.1007/s11708-021-0726-3

摘要： To improve the ignition behavior and to reduce the high NO emissions of blended pulverized fuels (PF) of semicoke (SC), large-scale experiments were conducted in a 300 kW fired furnace at various nozzle settings, i.e., ratios (denoted by / ) of the height of the rectangular burner nozzle to its width of 1.65, 2.32, and 3.22. The combustion tests indicate that the flame stability, ignition performance, and fuel burnout ratio were significantly improved at a nozzle setting of / = 2.32. The smaller / delayed ignition and caused the flame to concentrate excessively on the axis of the furnace, while the larger / easily caused the deflection of the pulverized coal flame, and a high-temperature flame zone emerged close to the furnace wall. NO emissions at the outlet of the primary zone decreased from 447 to 354 mg/m (O = 6%), and the ignition distance decreased from 420 to 246 mm when the / varied from 1.65 to 3.22. Furthermore, the ratio (denoted by / ) of the strong reduction zone area to the combustion reaction zone area was defined experimentally by the CO concentration to evaluate the reduction zone. The / rose monotonously, but its restraining effects on NO formation decreased as / increased. The results suggested that in a test furnace, regulating the nozzle / conditions sharply reduces NO emissions and improves the combustion efficiency of SC blends possessing an appropriate jet rigidity.

关键词： rectangular jet burner nozzle height to width ratio ignition characteristics pyrolyzed semicoke (SC) and bituminous blend NO_x formation

HTML PDF 收藏

基于双正交复序列的高效扩频调制方法

史小红

《中国工程科学》 2012年第14卷第3期页码 108-112

摘要：

提出了一种采用双正交复序列的高效扩频调制与解调方法（DoCS）。输入数据比特流被分割为长度为M的组，每组的M比特作为输入码字，从2M-2个长度为L的DoCS序列中选择一条序列进行发送，被选中的序列以QPSK方式调制在载波上，实现扩频通信。文中还提出了一种前向相位校正(FPC)方法来解决该系统中收发两端的载波同步问题。

关键词：调制与解调技术高效扩频调制前向相位校正双正交码

HTML PDF 收藏

频率脉宽实时独立调节的脉冲种子源 Research Articles

杨志伟1,2,吴旭1,2,欧阳德钦2,张恩诚2,孙慧斌1,阮双琛1,2

《信息与电子工程前沿（英文）》 2021年第22卷第10期页码 1379-1389 doi: 10.1631/FITEE.2000294

摘要：研制了一套基于嵌入式芯片的半导体激光器脉冲种子源，光脉冲频率和脉宽能独立实时调节，可在线从增益开关模式切换到准连续运行模式，以实现特定应用所需最佳光参数。为探讨半导体激光光源物理机制，对描述半导体激光腔内光子载流子瞬态变化的速率方程进行数值模拟与分析。之后，确定在设计驱动电路时需要考虑的问题。系统性能评估结果表明，光脉冲频率调节范围是250 Hz至42 MHz，光脉冲输出最窄脉宽为80 ps。脉冲种子源可驱动不同中心波长(1064、1550和1970 nm)半导体激光器，并可同时驱动两台半导体激光器，输出双频光脉冲。该脉冲种子源可作为一般高功率光学系统种子源，具有良好应用价值和广阔市场前景。

关键词：电参数控制；电子设计自动化及方法；光脉冲产生；光控制

HTML PDF 收藏

标题作者时间类型操作

Frequency-controlable sine signal based on PWM and its implementation on FPGA

Lianzhen HUANG, Jiangang LI, Dongjun ZHANG

期刊论文

Simulation of grid connection and maximum power point tracking control of brushless doubly-fed generator in wind power system

Hicham SERHOUD, Djilani BENATTOUS

期刊论文

Toward a nonlinear control of an AC-DC-PWM converter dedicated to induction heating

Amel HADRI-HAMIDA, S. ZEROUALI, A. ALLAG

期刊论文