Yuanqing Huang

Simulation Design of Inverter in Solar Photovoltaic System Based on MCU

A used solar power generation system based on the control of the microcontroller single-phase full-bridge inverter is designed in this paper. Inverter main circuit for the full-bridge inverter structure is formed by four IRF830A with SPWM frequency modulation work. After analysis and comparison, area, and so follow the example set by SPWM wave to calculate the duty cycle and design controller. AT89S51 as a chip to control, based on the Proteus and KeilC integrated development environment for system software design, software debugging of hardware circuits finally, the results show that all parts of indicators meet the requirements.

Study of photoacoustic imaging based on all-optical detection

Photoacoustic imaging is attracting increasing interests in biomedical imaging. The comparing between the traditional piezoelectric detections and optical detections is described. Three kinds of all-optical detection photoacoustic imaging systems, including system based on optical reflectance at a glass-liquid interface, system based on FP polymer film and the system based on POISe, are introduced and compared in this paper. Because these methods are difficult to realize measuring the photoacoustic signal on a 2D plane with the backward detection mode, a new kind of photoacoustic imaging system based on Electronic Speckle Pattern Interferometry (ESPI) is proposed. An ESPI outside displacement measurement system is adopted to detect the surface displacement of sample. Since the exposure time of a standard CCD which is of the order of tens of milliseconds, the temporal resolution to sample an acoustic field at MHz frequencies is achieved by interrogating the sensor with a short laser pulse whose bandwidth is about 20ns. After measuring and disposing the displacement data of the sample at a series detecting time, the photoacoustic image will be reconstructed by a delay and sum beam-forming algorithm or by a reconstruction algorithm based on the decomposition. In principle, the system will realize noncontact and backward-mode inspection and smaller element sizes of the receiver in the photoacoustic imaging application.

Control Simulation of Charge and Discharge in the Solar Photovoltaic Power Generation System

In the solar photovoltaic power generation system, the batteries in the total system cost of a large proportion. Batterys life is greatly influenced by the cost of electricity in the whole system. In this paper, develop a simple battery protection programmer - charge and discharge protection. The design of the battery charge and discharge control and simulation is completed from 51 core SM8954A SCM, T6963C LCD controller and the collection plate driver with Keil-Cx51 PROTEUS development of software and simulation software, its main contents include: hardware, system design process modules, simulation and debugging. With the real-time detection implementation of the battery terminal voltage can be adequately protected. The main battery charging and discharging process of the on-line terminal voltage detection, had been extended battery life, improved the system of the economy.

Vision guided automatic measuring in coordinate metrology

A novel automatically measuring planning method in coordinate metrology based on computer vision is presented in this paper. An active stereo vision system is established by attaching a CCD camera to the mechanical probe of the coordinate measuring machine (CMM). Through the movement of the probe of the CMM, as well as the camera, 3D edge characters of the object can be acquired, which are used as clues for automatically coordinate measuring. A multi-baseline matching method is presented to overcome the ambiguity in stereo matching, and a quadratic interpolating is used in sub pixel matching to get continuous depth image. The matching is only done on character edges in images, so it is much faster and more robust. Two methods of measuring path planning are put forward, in one way, a 2D characteristic edge image which are often stand for rapidly changes in depth or curvature of object surface can be acquired by projecting 3D edge characters to a scanning plane, and then the sampling points of mechanical probe are selected depending on the edge image. In the other way, surface patches are fitted to these 3D edges, and the sampling grid is determined by the type and area of every patch. Using these techniques, a highly automated high-speed, high-precision, 3-D coordinate acquisition system based on multiple-sensor integration can be developed. It has potential applications in manufacturing problems as metrology, inspection, and reverse engineering.

Tunable wavelength conversion based on cascaded sum and difference frequency generation with double-conversion configuration using M-QPM-LN waveguides

In this paper, we proposed a novel variable operation of a DC-OFS based on double SFG+DFG nonlinearity process with double-pass configuration for the first time. In this scheme, the available nonlinear crystal length is used twice: forward for SFG and backward for DFG in each conversion and this device is called double-pass SFG+DFG wavelength converter as the SF wave propagates twice in the waveguide. We used the novel multiple-quasi-phase-matched LiNbO3 (M-QPM-LN) waveguides having the continuously-phase-modulated domain structure, which can be operated by multiple pump wavelengths with minimum loss of efficiency. The frequency spacing of control signal-a is twice as large as the control signal-b. Conversion bandwidth is the frequency difference of control signal-b and control signal-a. We discussed Double-SFG+DFG-OFS with double-pass configuration theoretically and gave the formula of the input power of input signal, the two controlling light and pump light, which proposed a simple and feasible way to optimize the performance of the device. In this scheme, the advantages of the cascaded SFG+DFG scheme and the DC-OFS scheme are combined to a great extent. We believe this double-pass cascaded SFG+DFG DC-OFS must be better than single-pass cascaded SFG+DFG DC-OFS for constructing future flexible photonic networks.

Detection of Lung Cancer with Breath Biomarkers Based on SVM Regression

According to feature extraction of high order cumulant, a new method of detecting lung cancer is proposed applying support vector machine model to recognize the mixed Volatile Organic Compound (VOC) infrared spectrum, where the primary and secondary absorbed peaks are seriously overlapped. The number of spectrum channel of the original spectrum data is large; hence, the transmitted spectrogram is mapped to four-order cumulant space and detached from each firstly. In this simulation experiment, concentration of 19 VOCs was regressed by SVM and the result shows that the method performed well in identification. The average correct rate of component recognition is more than 95.5% when component concentration of VOC is not less than 1%. MSE and MAE were introduced to assess the performance of the method. Prediction adopting SVM and ANN is compared.

All-optical wavelength converter based on self-phase modulation in highly nonlinear photonic crystal fiber

A simple architecture of all-optical wavelength conversion in a highly nonlinear bismuth oxide-based photonic crystal fiber (PCF) is proposed, which consists of an erbium-doped fiber amplifier, a polarization controller, a nonlinear medium PCF, two tunable fiber Fabry-Perot filters and an optical isolator. Self-phase modulation is utilized to induce spectral broadening for all-optical wavelength conversion. The desired dispersion properties can be tailored by the parameters of bismuth oxide-based PCF microstructure. The propagation loss at 1550nm is about 0.8dB/m. The nonlinear coefficient is expected to be 1100W-1km-1 by using bismuth oxide-based glass and reducing the effective core area. The mode-field diameter of PCF is estimated to be 1.98μm and the predicted effective core area is 3.3μm2. The intermediate high numerical aperture fibers between bismuth oxide-based PCF and single-mode fibers are considered to reduce the splicing loss. The obtained results show that the all-optical wavelength converter has a potential of high conversion efficiency, wide conversion bandwidth, ultrafast response time, compact configuration and low insertion loss etc.

Double-Conversion Optical Frequency Shifter Using Multiple Quasi-Phase-Matched LiNbO3 Waveguides

In this paper, we proposed a variable operation of a DC-OFS based on double SFG+DFG (Double-SFG+DFG-OFS) nonlinearity process for the first time. We studied the principle and configuration of three DC-OFS in detail both theoretically and experimentally. In order to compare with Double-DFG-OFS and Double-SHG+DFG-OFS, we also used two four-channel-controlling multiple-quasi-phase-matched LiNbO3 wavelength converters and got ten different outputs spreading across a wavelength range of as broad as 35 nm by changing the combination of two controlling wavelengths of the two wavelength converters. And one channel signal was converted to shorter and longer wavelength and the same wavelength by changing the controlling wavelengths. We got higher conversion efficiency compared with the other two DC-OFSs mentioned above. We used novel M-QPM-LN wavelength converters having a continuously-phase- modulated domain structure, which can be operated by multiple pump wavelengths with minimum loss of efficiency. The periods were 14.8μm. The phase of the periodic poling was continuously modulated to satisfy the QPM condition at four different wavelengths. The frequency spacing of control signal-b is twice as large as the control signal-a. The operating temperatures were 102.5 and 100.5 C for the first and the second QPM-LN wavelength converters, respectively.

Novel scheme to increase the operation speed of a SOA for all-optical wavelength conversion

All-optical wavelength converters (AOWCs) are considered to be important components in future wavelength-division-multiplexed (WDM) networks. Cross gain modulation schemes in semiconductor optical amplifiers (SOA) are promising candidates for an all-optical wavelength conversion application due to the simple implementation and effective conversion. However, the slow gain recovery time of SOA limits the maximum operation speed and causes unwanted pattern effects. This paper provides a novel scheme for wavelength conversion enables ultra-fast conversion speed. On the one hand, we utilize a three-wavelength-device (TWD) to reduce the recovery time of the SOA. On the other hand, we use an optical band pass filter (OBF) which central wavelength is blue shifted with respect to the central wavelength of the probe beam to increase the frequency response. The combination of a reduction of the SOA recovery time and an increase of the frequency response enables conversion speed potentially to achieve 160 Gb/s or even faster.

Recirculating configuration all-optical wavelength conversion by self-phase modulation in a highly nonlinear photonic crystal fiber

A novel architecture of all-optical wavelength conversion in a highly nonlinear bismuth oxide-based photonic crystal fiber (PCF) is demonstrated. Self-phase modulation is utilized to induce spectral broadening for the all-optical wavelength converter. A recirculating configuration is designed to obtain the twice spectral broadening. Therefore, wavelength conversion is achieved. The design and the simulation of PCF are demonstrated. The desired dispersion properties can be tailored by the parameters of bismuth oxide (Bi2O3) PCF microstructure. The propagation loss at 1550nm is about 0.8dB/m. The simulation results of PCF indicate the relationship of the effective index of the fundamental mode, the mode effective area and the holes pitch of PCF. The nonlinear coefficient is expected to be 1100W-1km-1 by using bismuth oxide-based glass and reducing the effective core area. The mode-field diameter of PCF is estimated to be 1.98μm and the predicted small effective core area is 3.3μm2. The design of Bi2O3-based PCF and the intermediate high numerical aperture fibers between Bi2O3-based PCF and single-mode fibers are considered to reduce the splicing loss. The obtained results show that the wavelength converter has a potential of wide conversion bandwidth, high response time, simple configuration and low insertion loss etc.