Description: 对原始信号做DCT的算法:Cox 和Piva 等人提出的DCT技术的经典之作。Cox利用随机数发生器产生标准正态序列作为水印信息对图像进行整体DCT变换后,选取除去DC系数之外部分较低频率系数叠加水印信息 Piva则修改整幅图像的中频部分。对原始信号分块后,再作DCT的算法:Hsu和Wu 把图像进行8*8分块,将一个二进制序列作为水印放入DCT的中频区;有些学者则计算整个图像的DCT,把一个实数序列嵌入DCT的中频系数上。选择中频区的好处是一方面尽量减少嵌入信息对图像主观视觉的影响;同时,尽量避免有损压缩对水印信息可能带来的损失。还有一种DCT方法就是把水印信息嵌入到高频系数上,但是采用这种方法,抗压缩性非常差。-done to the original signal DCT algorithm : Cox Piva and others made the DCT technology classic. Cox using random number generator producing standard normal sequence information as a watermark image of the overall DCT, DC coefficient selection removed outside some lower frequency coefficient superposition watermark information Piva will be replaced by images of the entire IF part. The original signal block, before making the DCT algorithm : Wu Hsu and put images 8* 8 block, a binary sequence as watermarks Add DCT IF; Some scholars calculated whole image of DCT, a real sequence embedded IF DCT coefficients. IF the choice is a good one to minimize the embedded information to the subjective visual images; Meanwhile, try to avoid Compression right watermark information possible losses. There Platform: |
Size: 33792 |
Author:圣子到 |
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Description: 本文件是一个SPWM逆变器的仿真源文件,可以在MATLAB7.1中直接运行。设计中PWM Generator采用外部调制信号,并在调制信号中注入了三次谐波,很好的抑制了输出谐波,同时提高了直流电源的利用率。-This document is a SPWM inverter simulation source file, you can directly run MATLAB7.1. Design of PWM Generator external modulation signal, and in the modulation signal into the third harmonic, the output of good harmonic suppression, while improving the utilization of the DC power supply. Platform: |
Size: 67584 |
Author:李勇 |
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Description: 包里有直流发电机simulink模型,用于直流发电机的控制仿真。-Bag simulink model has DC generator, DC generator for the control simulation. Platform: |
Size: 27648 |
Author:qiuguilin |
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Description: 基于单位功率因数控制策略的三相全控整流。开关器件采用IGBT。PWM波形产生控制电路里使用的饱和限制模块,就是限制波形的幅度的,对输出直流电压幅值影响很大。-Based on the unity power factor control strategy of three-phase full-controlled rectifier. Switching device IGBT. PWM waveform generator control circuit in the saturation limit the use of modules, is to restrict the range of waveform and amplitude of the output DC voltage impact. Platform: |
Size: 8192 |
Author:雷宾 |
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Description: 电力电子元件模拟同步发电机,实现AC/DC,DC/AC,利用计算法PWM,PID控制器,跟据效果比较理想-Synchronous generator simulation of power electronic components, to achieve AC/DC, DC/AC, using computational method PWM, PID controller, with far more satisfactory results Platform: |
Size: 17408 |
Author:Jerry Xu |
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Description: Utility restructuring, technology evolution,
public environmental policy, and expanding power
demand are providing the opportunity for microturbines
to become important energy resources. In order to
investigate the ability of microturbine units in
distribution systems, new simulation tools are needed.
This paper presents a dynamic models for microturbines.
For the purpose of modeling initialy a dynamic model
for each component in the system, including gas turbine,
permanent magnet generator, DC bridge rectifier and
power inverter is developed and after this stage the
model is implemented in a simulation software. In this
research the simulation tool is Matlab/Simulink. Also the
systems stand-alone dynamic performances is analyzed
and evaluated. Platform: |
Size: 307200 |
Author:proust |
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Description: 由MATLAB程序产生2Gbi/s的基带OFDM信号先将2^15-1个伪随机序列映射到256个进行4QAM编码调制的子载波上,编码后的OFDM符号再经过IFFT变换将其转换为时域波形,接着添加6.4ns的循环前缀(CP),产生的数据波形再装载到Tektronix任意波形发生器(AWG)中,产生2Gbit/s的基带OFDM信号。基带OFDM信号频谱示意图如图3所示。其中包括256个OFDM子载波256个子载波中200个子信道用来传送数据信号,27个高频和28个低频子信道为了过采样的需要置0,OFDM频谱中最中间的那个子信道由于基带信号的直流成分大也被置0。-Generated by the MATLAB program 2Gbi/s baseband OFDM signal the first 2 ^ 15-1 pseudo-random sequence is mapped to 256 for 4QAM code modulation subcarriers, OFDM symbol after the re-encoded after IFFT transformation to convert it too domain waveform, and then add 6.4ns the cyclic prefix (CP), the data generated by Tektronix waveform and then loaded into the arbitrary waveform generator (AWG), resulting in 2Gbit/s baseband OFDM signal. Schematic diagram of the baseband OFDM signal spectrum shown in Figure 3. Including 256 sub-carrier OFDM subcarriers 256, 200 subchannels used to transmit data signals, 27 high and 28 low-frequency sub-channel over-sampling of the need to set 0, OFDM spectrum in the most middle of the baseband sub-channel as large DC component signal is also set to 0. Platform: |
Size: 220160 |
Author:QQ |
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Description: The fast control capability of the VSC-HVDC and
the process of area mode oscillations are analyzed. An auxiliary
fuzzy logic controller designed in Matlab for the Voltage Source
Converter based HVDC transmission system, VSC-HVDC, to
improve the stability of the AC/ DC system is designed to enhance
stability by increasing the deceleration energy of oscillation.
Simulation results on the IEEE 4-generator AC/DC power
systems have shown that the controller can enhance the dynamic
stability of interconnected power systems effectively and is robust
to the variation of system operating conditions and oscillation
modes. Platform: |
Size: 345088 |
Author:Bidyut Hota |
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Description: Hybrid PV-wind generation shows higher
availability as compared to PV or wind alone. For rural
electrifications, researches are focused on hybrid power system
which provides sustainable power. The variable voltage and
frequency of the self excited induction generator (SEIG) is
rectified through Vienna rectifier (three switches) to the required
D.C voltage level and fed to common D.C bus. The variable output
voltage of PV module is controlled by DC/DC converter using
proposed fuzzy logic controller and fed to common D.C bus. The
DC bus collects the total power from the wind and photovoltaic
system and used to charge the battery as well as to supply the A.C
loads through inverter. A dynamic mathematical model and
MATLAB simulations for the entire scheme is presented. Results
from the simulations and experimental tests bring out the
suitability of the proposed hybrid scheme in remote areas. Platform: |
Size: 48128 |
Author:hareesh |
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Description: 直流发电机的所有相关例程的MATLAB/simulink仿真实例,对大家学习直流电动机有很大的帮助。-Dc generator all related routines of MATLAB/simulink simulation examples, is of great help for everybody to learn dc motor.
Platform: |
Size: 27648 |
Author:siwenxu |
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Description: 全面的对直流电动机和发电机特性进行仿真研究,对于异步电机启动、调速和坐标变换进行建模仿真,同时给出了同步电机的坐标变换模型。-A comprehensive simulation study of DC motor and generator characteristics for asynchronous motor starting, speed control and coordinate transformation for modeling and simulation, and gives the coordinate transformation model of synchronous motor. Platform: |
Size: 15502336 |
Author:张三 |
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Description: From the late nineteenth century through the middle of the twentieth century, DC-to-AC power conversion was accomplished using rotary converters or motor-generator sets (M-G sets). In the early twentieth century, vacuum tubes and gas filled tubes began to be used as switches in inverter circuits. The most widely used type of tube was the thyratron.
The origins of electromechanical inverters explain the source of the term inverter. Early AC-to-DC converters used an induction or synchronous AC motor direct- Platform: |
Size: 14336 |
Author:SOLARA |
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Description: From the late nineteenth century through the middle of the twentieth century, DC-to-AC power conversion was accomplished using rotary converters or motor-generator sets (M-G sets). In the early twentieth century, vacuum tubes and gas filled tubes began to be used as switches in inverter circuits. The most widely used type of tube was the thyratron.
The origins of electromechanical inverters explain the source of the term inverter. Early AC-to-DC converters used an induction or synchronous AC motor Platform: |
Size: 301056 |
Author:SOLARA |
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Description: 论证表明混合动力电动汽车在一个完整的循环中有不同的运行模式:加速、巡航、对电池进行加速和再生制动。
电气子系统由电动机、发电机、蓄电池和DC/DC转换器四部分组成。
行星齿轮子系统对动力分流装置进行建模。它使用一个行星装置,通过分配和组合发动机、马达和发电机来传递机械动力。
内燃机子系统采用调速器对57 kW @ 6000转/分汽油发动机进行建模发动机调速器。
车辆动力学系统模型车辆的所有机械部件。(The demonstration shows different operating modes of the HEV over one complete cycle: accelerating, cruising, recharging the battery while accelerating and regenerative braking.
The Electrical Subsystem is composed of four parts: The electrical motor, the generator, the battery, and the DC/DC converter.
The Planetary Gear Subsystem models the power split device. It uses a planetary device, which transmits the mechanical motive force from the engine, the motor and the generator by allocating and combining them.
The Internal Combustion Engine subsystem models a 57 kW @ 6000 rpm gasoline fuel engine with speed governor.) Platform: |
Size: 604160 |
Author:xll106 |
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Description: MATLAB模型,双馈风电机组基于最大功率跟踪,低风速超速控制,中风速高风速变桨距控制(DFIG MATLABThe wind turbine and the doubly-fed induction generator (WTDFIG) are shown in the figure called The Wind Turbine and the Doubly-Fed Induction Generator System. The AC/DC/AC converter is divided into two components: the rotor-side converter (Crotor) and the grid-side converter (Cgrid). Crotor and Cgrid are Voltage-Sourced Converters that use forced-commutated power electronic devices (IGBTs) to synthesize an AC voltage from a DC voltage source. A capacitor connected on the DC side acts as the DC voltage source. A coupling inductor L is used to connect Cgrid to the grid. The three-phase rotor winding is connected to Crotor by slip rings and brushes and the three-phase stator winding is directly connected to the grid. The power captured by the wind turbine is converted into electrical power by the induction generator and it is transmitted to the grid by the stator and the rotor windings.) Platform: |
Size: 82944 |
Author:zzZZ0202 |
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