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Investigation on the automatic parameters extraction of pulse signals based on wavelet transform 被引量:8
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作者 WANG Hui-yan ZHANG Pei-yong 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第8期1283-1289,共7页
This paper analyses a key problem in the quantification of pulse diagnosis. Due to the subjectivity and fuzziness of pulse diagnosis,quantitative methods are needed. To extract the parameters of pulse signals,the prer... This paper analyses a key problem in the quantification of pulse diagnosis. Due to the subjectivity and fuzziness of pulse diagnosis,quantitative methods are needed. To extract the parameters of pulse signals,the prerequisite is to detect the corners of pulse signals correctly. Up to now,the pulse parameters are mostly acquired by marking the pulse corners manually,which is an obstacle to modernize pulse diagnosis. Therefore,a new automatic parameters extraction approach for pulse signals using wavelet transform is presented. The results testified that the method we proposed is feasible and effective and can detect corners of pulse signals accurately,which can be expected to facilitate the modernization of pulse diagnosis. 展开更多
关键词 pulse signal Feature extraction Complex wavelet transform Quantitative diagnosis
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Study on the Classification of Pulse Signal Based on the BP Neural Network 被引量:4
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作者 Shaohua Wang Jianli Jiang Xiaobing Lu 《Journal of Biosciences and Medicines》 2020年第5期104-112,共9页
The objectification of the pulse signal analysis is a practical problem. The classification of the pulse signal is studied based on the BP neural network. It is first analyzed how to select the characteristic factors ... The objectification of the pulse signal analysis is a practical problem. The classification of the pulse signal is studied based on the BP neural network. It is first analyzed how to select the characteristic factors of the pulse signal. Then the method of nondimensionalization/normalization on the pulse signal is presented to preprocess the characteristic factors. The classification of the pulse signal and the effects of the selection of characteristic factors are studied by using the normalized data and BP neural network. It is shown that nondimensionalization/normalization of the data is in favor of the training and forecasting of the network. The selection of characteristic factors affects the accuracy of forecasting obviously. The results of forecasting by selection of 8, 6 and 4 factors respectively show that the less the factors are, the worse the effects are. 展开更多
关键词 BP NEURAL Network pulse signal CLASSIFICATION DIMENSIONAL Analysis
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Digitalization of inverting filter shaping circuit for nuclear pulse signals 被引量:7
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作者 Huai-Qiang Zhang Hong-Tao Shi +1 位作者 Zhuo-Dai Li Yu-Wen Li 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第9期16-24,共9页
In the design of filter shaping circuits for nuclear pulse signals,inverting filter shaping circuits perform better than non-inverting filter shaping circuits.Because these circuits facilitate changing the phase of a ... In the design of filter shaping circuits for nuclear pulse signals,inverting filter shaping circuits perform better than non-inverting filter shaping circuits.Because these circuits facilitate changing the phase of a pulse signal,they are widely used in processing nuclear pulse signals.In this study,the transfer functions of four types of inverting filter shaping circuits,namely the common inverting filter shaping,improved inverting filter shaping,multiple feedback low-pass filter shaping,and third-order multiple feedback low-pass filter shaping,in the Laplacian domain,are derived.We establish the numerical recursive function models and digitalize the four circuits,obtain the transfer functions in the Z domain,and analyze the filter performance and amplitude-frequency response characteristics in the frequency domain.Based on the actual nuclear pulse signal of the Si-PIN detector,we realize four types of inverting digital shaping.The results show that under the same shaping parameters,the common inverting digital shaping has better amplitude extraction characteristics,the third-order multiple feedback low-pass digital shaping has better noise suppression performance,and the multiple feedback digital shaping takes into account both pulse amplitude extraction and noise suppression performance. 展开更多
关键词 Nuclear pulse signal Inverting filter shaping circuit Digital shaping Amplitude-frequency response
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DETECTING TECHNIQUE OF WEAK PERIODIC PULSE SIGNAL VIA SYNTHESIS OF CROSS-CORRELATION AND CHAOTIC SYSTEM 被引量:4
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作者 LiYue YangBaojun +1 位作者 LuPeng LiShizhe 《Journal of Electronics(China)》 2003年第5期397-400,共4页
In this letter, with the synthesis of usual cross-correlation detecting method andchaotic detecting method, a new detecting system for the weak periodic pulse signal is constituted,in which the two methods can play re... In this letter, with the synthesis of usual cross-correlation detecting method andchaotic detecting method, a new detecting system for the weak periodic pulse signal is constituted,in which the two methods can play respective preponderance. Theoretical analyses and simulationstudies have shown that the detecting system is very sensitive to the periodic pulse signal understrong noise background and has exceedingly powerful capability of suppressing complex noise. 展开更多
关键词 CROSS-CORRELATION Chaotic system signal detection Periodic pulse signal signal-to-Noise Ratio (SNR)
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A model for automatic identification of human pulse signals 被引量:2
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作者 Hui-yan WANG Pei-yong ZHANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1382-1389,共8页
This paper presents a quantitative method for automatic identification of human pulse signals. The idea is to start with the extraction of characteristic parameters and then to construct the recognition model based on... This paper presents a quantitative method for automatic identification of human pulse signals. The idea is to start with the extraction of characteristic parameters and then to construct the recognition model based on Bayesian networks. To identify depth, frequency and rhythm, several parameters are proposed. To distinguish the strength and shape, which cannot be represented by one or several parameters and are hard to recognize, the main time-domain feature parameters are computed based on the feature points of the pulse signal. Then the extracted parameters are taken as the input and five models for automatic pulse signal identification are constructed based on Bayesian networks. Experimental results demonstrate that the method is feasible and effective in recognizing depth, frequency, rhythm, strength and shape of pulse signals, which can be expected to facilitate the modernization of pulse diagnosis. 展开更多
关键词 pulse signal identification Feature extraction Bayesian network Quantitative diagnosis Wavelet transform
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Investigation of blood pulse PPG signal regulation on toe effect of body posture and lower limb height 被引量:2
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作者 XIN Shang-zhi HU Sijung +4 位作者 CRABTREE Vincent P. ZHENG Jia AZORIN-PERIS Vincent ECHIADIS Angelos SMITH Peter R. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第6期916-920,共5页
Objective: To study the regulation of blood pulse volume via photoplethysmography (PPG) signal detected from toe, while the lower limb is passively raised in different height positions. Methods: Use a modified non-inv... Objective: To study the regulation of blood pulse volume via photoplethysmography (PPG) signal detected from toe, while the lower limb is passively raised in different height positions. Methods: Use a modified non-invasive PPG technique to detect the blood pulse signal on toe with infrared (IR) photo sensor. A protocol consisting of two postures, i.e., supine and 45° reclining, was designed to conduct laboratory trial in this study. During the period of performing the protocol of these postures, the lower limb was passively raised from the heights of 10 cm to 60 cm randomly and individually with sponge blocks underneath the foot. Results: In the supine posture, the higher the foot was passively raised, the more the blood PPG signal decreased. In the 45° reclining posture, the blood PPG signal increased at the beginning and then decreased in the foot height position from 10 cm to 60 cm. In both postures the normalized AC signal changes significantly while the normalized DC signal changes little. Conclusion: The toe PPG signals can obviously indicate the regulated blood volume change with the designated postural procedures due to the heart level position. 展开更多
关键词 Photoplethysmographv (PPG) NON-INVASIVE Body posture Blood pulse volume signal Lower limb
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Development of a wide-range and fast-response digitizing pulse signal acquisition and processing system for neutron flux monitoring on EAST 被引量:2
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作者 Li Yang Hong-Rui Cao +7 位作者 Jin-Long Zhao Zi-Han Zhang Qiang Li Guo-Bin Wu Yong-Qiang Zhang Guo-Qiang Zhong Li-Qun Hu Zi-Jun Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第3期126-136,共11页
The neutron count rate fluctuation reaches six orders of magnitude between the ohmic plasma scenario and high power of auxiliary heating on an experimental advanced superconducting tokamak(EAST).The measurement result... The neutron count rate fluctuation reaches six orders of magnitude between the ohmic plasma scenario and high power of auxiliary heating on an experimental advanced superconducting tokamak(EAST).The measurement result of neutron flux monitoring(NFM)is a significant feedback parameter related to the acquisition of radiation protection-related information and rapid fluctuations in neutron emission induced by plasma magnetohydrodynamic activity.Therefore,a wide range and high time resolution are required for the NFM system on EAST.To satisfy these requirements,a digital pulse signal acquisition and processing system with a wide dynamic range and fast response time was developed.The present study was conducted using a field-programmable gate array(FPGA)and peripheral component interconnect extension for instrument express(PXIe)platform.The digital dual measurement modes,which are composed of the pulse-counting mode and AC coupled square integral's Campbelling mode,were designed to expand the measurement range of the signal acquisition and processing system.The time resolution of the signal acquisition and processing system was improved from 10 to 1 ms owing to utilizing highspeed analog-to-digital converters(ADCs),a high-speed PXIe communication with a direct memory access(DMA)mode,and online data preprocessing technology of FPGA.The signal acquisition and processing system was tested experimentally in the EAST radiation field.The test results showed that the time resolution of NFM was improved to 1 ms,and the dynamic range of the neutron counts rate was expanded to more than 10^(6) counts per second.The Campbelling mode was calibrated using a multipoint average linear fitting method;subsequently,the fitting coefficient reached 0.9911.Therefore,the newly developed pulse signal acquisition and processing system ensures that the NFM system meets the requirements of high-parameter experiments conducted on EAST more effectively. 展开更多
关键词 EAST Neutron flux monitoring High time resolution Wide range pulse signal acquisition and processing system
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Locally Optimum Detection of Weak Pulse Signals in Non-Gaussian Noise 被引量:1
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作者 Liang Min and Sun ZhongkangDept. of Electronic Eng., National University of Defence Technology, Changsha 410073, Hunan, China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1991年第1期74-80,共7页
In this paper, the problem of locally optimum detection of weak pulse signals in narrow-band non-Gaussian noise is discussed. A generalized model is proposed for locally optimum detectors (LOD) and the corresponding p... In this paper, the problem of locally optimum detection of weak pulse signals in narrow-band non-Gaussian noise is discussed. A generalized model is proposed for locally optimum detectors (LOD) and the corresponding physical meaning is explained. On the basis of this generalized model, the LOD structures are derived for detecting both coherent- and incoherent-pulse signals in narrow-band non-Gaussian noise. The asymptotic relative efficiency (ARE) due to Pitman is used to evaluate the performance of these LODs. Finally, numerical calculations are carried out for the AREs of these LODs and some valuable results are obtained. 展开更多
关键词 Asymptotic relatie efficiency Locally optimum detector pulse signal.
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Application of Wavelet Packet Energy Spectrum to Extract the Feature of the Pulse Signal 被引量:2
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作者 曹佃国 武玉强 +1 位作者 石学文 王鹏 《Journal of Measurement Science and Instrumentation》 CAS 2010年第3期304-306,共3页
The wavelet packet is presented as a new kind of multiscale analysis technique followed by Wavelet analysis. The fundamental and realization arithmetic of the wavelet packet analysis method are described in this paper... The wavelet packet is presented as a new kind of multiscale analysis technique followed by Wavelet analysis. The fundamental and realization arithmetic of the wavelet packet analysis method are described in this paper. A new application approach of the wavelet packed method to extract the feature of the pulse signal from energy distributing angle is expatiated. It is convenient for the microchip to process and judge by using the wavelet packet analysis method to make the pulse signals quantized and analyzed. Kinds of experiments are simulated in the lab, and the experiments prove that it is a convenient and accurate method to extract the feature of the pulse signal based on wavelet packed-energy spectrumanalysis. 展开更多
关键词 wavelet packed energy spectrum pulse signal
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A theoretical study of the signal enhancement mechanism of coaxial DP-LIBS
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作者 宋震 王俊霄 +11 位作者 王钢 张雷 王树青 张婉飞 马晓飞 刘珍荣 罗学彬 马维光 叶泽甫 朱竹君 尹王保 贾锁堂 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第5期156-164,共9页
In the field of dual-pulse laser-induced breakdown spectroscopy(DP-LIBS)research,the pursuit of methods for determining pulse intervals and other parameters quickly and conveniently in order to achieve optimal spectra... In the field of dual-pulse laser-induced breakdown spectroscopy(DP-LIBS)research,the pursuit of methods for determining pulse intervals and other parameters quickly and conveniently in order to achieve optimal spectral signal enhancement is paramount.To aid researchers in identification of optimal signal enhancement conditions and more accurate interpretation of the underlying signal enhancement mechanisms,theoretical simulations of the spatiotemporal processes of coaxial DP-LIBS-induced plasma have been established in this work.Using a model based on laser ablation and two-dimensional axisymmetric fluid dynamics,plasma evolutions during aluminum–magnesium alloy laser ablation under single-pulse and coaxial dualpulse excitations have been simulated.The influences of factors,such as delay time,laser fluence,plasma temperature,and particle number density,on the DP-LIBS spectral signals are investigated.Under pulse intervals ranging from 50 to 1500 ns,the time evolutions of spectral line intensity,dual-pulse emission enhancement relative to the single-pulse results,laser irradiance,spatial distribution of plasma temperature and species number density,as well as laser irradiance shielded by plasma have been obtained.The study indicates that the main reason behind the radiation signal enhancement in coaxial DP-LIBS-induced plasma is attributed to the increased species number density and plasma temperature caused by the second laser,and it is inferred that the shielding effect of the plasma mainly occurs in the boundary layer of the stagnation point flow over the target surface.This research provides a theoretical basis for experimental research,parameter optimization,and signal enhancement tracing in DP-LIBS. 展开更多
关键词 laser-induced plasma radiation fluid dynamics model double pulse laser-induced breakdown spectroscopy(DP-LIBS) laser ablation signal enhancement mechanism
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Analysis of random laser scattering pulse signals with lognormal distribution
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作者 闫振纲 卞保民 +3 位作者 王绶玙 林颖璐 王春勇 李振华 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期246-256,共11页
The statistical distribution of natural phenomena is of great significance in studying the laws of nature. In order to study the statistical characteristics of a random pulse signal, a random process model is proposed... The statistical distribution of natural phenomena is of great significance in studying the laws of nature. In order to study the statistical characteristics of a random pulse signal, a random process model is proposed theoretically for better studying of the random law of measured results. Moreover, a simple random pulse signal generation and testing system is designed for studying the counting distributions of three typical objects including particles suspended in the air, standard particles, and background noise. Both normal and lognormal distribution fittings are used for analyzing the experimental results and testified by chi-square distribution fit test and correlation coefficient for comparison. In addition, the statistical laws of three typical objects and the relations between them are discussed in detail. The relation is also the non-integral dimension fractal relation of statistical distributions of different random laser scattering pulse signal groups. 展开更多
关键词 random pulse signal statistical self-similarity lognormal distribution laser scattering
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INTELLIGENT CONTROL SYSTEM OF PULSED MAG WELDING INVERTER BASED ON DIGITAL SIGNAL PROCESSOR
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作者 WU Kaiyuan HUANG Shisheng WU Shuifeng LI Xinglin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第6期86-90,共5页
A fuzzy logic intelligent control system of pulsed MAG welding inverter based on digital signal processor (DSP) is proposed to obtain the consistency of arc length in pulsed MAG welding. The proposed control system ... A fuzzy logic intelligent control system of pulsed MAG welding inverter based on digital signal processor (DSP) is proposed to obtain the consistency of arc length in pulsed MAG welding. The proposed control system combines the merits of intelligent control with DSP digital control. The fuzzy logic intelligent control system designed is a typical two-input-single-output structure, and regards the error and the change in error of peak arc voltage as two inputs and the background time as single output. The fuzzy logic intelligent control system is realized in a look-up table (LUT) method by using MATLAB based fuzzy logic toolbox, and the implement of LUT method based on DSP is also discussed. The pulsed MAG welding experimental results demonstrate that the developed fuzzy logic intelligent control system based on DSP has strong arc length controlling ability to accomplish the stable pulsed MAG welding process and controls pulsed MAG welding inverter digitally and intelligently. 展开更多
关键词 pulsed MAG welding inverter Arc length control Fuzzy logic intelligent control Digital signal processor (DSP)
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Automatic de-noising and recognition algorithm for drilling fluid pulse signal
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作者 HU Yongjian HUANG Yanfu LI Xianyi 《Petroleum Exploration and Development》 2019年第2期393-400,共8页
Wavelet forced de-noising algorithm is suitable for denoising of unsteady drilling fluid pulse signal, including baseline drift rectification and two-stage de-noising processing of frame synchronization signal and ins... Wavelet forced de-noising algorithm is suitable for denoising of unsteady drilling fluid pulse signal, including baseline drift rectification and two-stage de-noising processing of frame synchronization signal and instruction signal. Two-stage de-noising processing can reduce the impact of baseline drift and determine automatic peak detection threshold range for signal recognition by distinguishing different features of frame synchronization pulse and instruction pulse. Rising and falling edge relative protruding threshold is defined for peak detection in signal recognition, which can make full use of the degree of the signal peak change and detect peaks flexibly with rising and falling edge relative protruding threshold combination. A synchronous decoding method was designed to reduce position uncertainty of the frame synchronization pulse and eliminate the accumulative error of time base drift, which determines the first instruction pulse position according to position of the frame synchronization pulse and decodes subsequent instruction pulse by taking current instruction pulse as new bit synchronization pulse. Special tool software was developed to tune algorithm parameters, which has a decoding success rate of about 95% for the universal coded signals. For the special coded signals with check byte, decoding success rate using the automatic threshold adjustment algorithm is as high as 99%. 展开更多
关键词 drilling fluid pulse signal signal processing DECODING SUCCESS rate AUTOMATIC DE-NOISING and recognition wavelet FORCED DE-NOISING peak detection synchronous DECODING
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Pulse Signal Recovery Method Based on Sparse Representation
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作者 Jiangmei Zhang Haibo Ji +2 位作者 Qingping Zhu Hongsen He Kunpeng Wang 《Journal of Beijing Institute of Technology》 EI CAS 2018年第2期161-168,共8页
Pulse signal recovery is to extract useful amplitude and time information from the pulse signal contaminated by noise. It is a great challenge to precisely recover the pulse signal in loud background noise. The conven... Pulse signal recovery is to extract useful amplitude and time information from the pulse signal contaminated by noise. It is a great challenge to precisely recover the pulse signal in loud background noise. The conventional approaches,which are mostly based on the distribution of the pulse energy spectrum,do not well determine the locations and shapes of the pulses. In this paper,we propose a time domain method to reconstruct pulse signals. In the proposed approach,a sparse representation model is established to deal with the issue of the pulse signal recovery under noise conditions. The corresponding problem based on the sparse optimization model is solved by a matching pursuit algorithm. Simulations and experiments validate the effectiveness of the proposed approach on pulse signal recovery. 展开更多
关键词 signal recovery pulse signal sparse representation matching pursuit
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Optimal Periodic Pulse Jamming Signal Design for QPSK Systems
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作者 Jie Yang Bingyang Han Jingying Xu 《Journal of Beijing Institute of Technology》 EI CAS 2017年第3期381-387,共7页
The problem of optimal periodic pulse jamming design for a quadrature phase shift keying(QPSK)communication system is investigated.First a closed-form bit-error-rate(BER)of QPSK system under the jamming of pulse s... The problem of optimal periodic pulse jamming design for a quadrature phase shift keying(QPSK)communication system is investigated.First a closed-form bit-error-rate(BER)of QPSK system under the jamming of pulse signal is derived.Then the asymptotic performance of the derived BER is analyzed as the signal-to-noise ratio(SNR)grows to infinity.In order to maximize the BER of the QPSK system,the optimal parameters of periodic pulse jamming signal,including the duty cycle and signal-tojamming power ratio(SJR),are found out.Numerical results are presented to verify our analytical results and the optimality of our design. 展开更多
关键词 quadrature phase shift keying(QPSK) pulse jamming optimal jamming bit-error-rate(BER) signal-to-noise ratio (SNR) duty cycle signal-to-jamming ratio (S JR)
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Optimal parameter choice of CR–RC^m digital filter in nuclear pulse processing 被引量:9
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作者 Huai-Qiang Zhang Zhuo-Dai Li +1 位作者 Bin Tang He-Xi Wu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第7期42-46,共5页
CR–RCm filters are widely used in nuclear energy spectrum measurement systems. The choice of parameters of a CR–RCm digital filter directly affects its performance in terms of energy resolution and pulse count rate ... CR–RCm filters are widely used in nuclear energy spectrum measurement systems. The choice of parameters of a CR–RCm digital filter directly affects its performance in terms of energy resolution and pulse count rate in digital nuclear spectrometer systems. A numerical recursive model of a CR differential circuit and RC integration circuit is derived, which shows that the shaping result of CR–RCm is determined by the adjustment parameter (k, it determines the shaping time of the shaper) and the integral number (m). Furthermore, the amplitude– frequency response of CR–RC^m is analyzed, which shows that it is a bandpass filter;the larger the shaping parameters (k and m), the narrower is the frequency band. CR–RC^m digital Gaussian shaping is performed on the actual sampled nuclear pulse signal under different shaping parameters. The energy spectrum of 137Cs is measured based on the LaBr3(Ce) detector under different parameters. The results show that the larger the shaping parameters (m and k), the closer the shaping result is to Gaussian shape, the wider is the shaped pulse, the higher is the energy resolution, and the lower is the pulse count rate. For the same batch of pulse signals, the energy resolution is increased from 3.8 to 3.5%, and the full energy peak area is reduced from 7815 to 6503. Thus, the optimal shaping parameters are m -3 and k -0.95. These research results can provide a design reference for the development of digital nuclear spectrometer measurement systems. 展开更多
关键词 CR-RCm digital filter NUCLEAR pulse signal GAUSSIAN SHAPING Energy resolution
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Study on the method of polarization suppression of cheating jamming in pulse Doppler radar 被引量:5
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作者 SongLizhong QiaoXiaolin MengXiande JinMing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期310-315,共6页
A jamming suppression method based on polarization signal detection is proposed under common range and velocity cheating jammingfor pulse Doppler radar. On the basis of the separation of the target and the jamming, th... A jamming suppression method based on polarization signal detection is proposed under common range and velocity cheating jammingfor pulse Doppler radar. On the basis of the separation of the target and the jamming, the range and velocity track on the true target are realized. Firstly the signal processing model of the full polarization pulse Doppler radar is introduced. Secondly the method of correct target separation is discussed, which is the twice detections of energy and polarization state on the two dimension resolution cells of range and velocity of the radar echo. Finally the simulations are performed and the results prove the validity. What's more, multiple range and velocity cheating jamming can be suppressed at the same time if the target and the jamming are different in the polarization domain. 展开更多
关键词 pulse Doppler radar POLARIZATION signal detection.
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Analysis of Enhanced Laser-Induced Breakdown Spectroscopy with Double Femtosecond Laser Pulses 被引量:3
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作者 沈洁 杨正才 +4 位作者 刘小亮 史彦超 赵培茜 孙少华 胡碧涛 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第2期147-152,共6页
In this paper, an experimental study of collinear geometry double-pulse femtosecond LIBS was performed on a Ni sample in ambient air in an effort to clarify the contributing processes responsible for the signal enhanc... In this paper, an experimental study of collinear geometry double-pulse femtosecond LIBS was performed on a Ni sample in ambient air in an effort to clarify the contributing processes responsible for the signal enhancement observed in comparison with the single-pulse case. Doublepulse LIBS spectra show a very clear enhancement when an optimum inter-pulse delay was used. The influences of the inter-pulse delay between two pulses on the LIBS signal intensity, electron temperature and density were investigated. It is most remarkable that the evolutions of signal enhancement and electron temperature versus the inter-pulse delay showed the same behavior and revealed two main regimes of interaction. These results provide additional insight into the possible emission enhancement mechanisms in the double pulse configuration. 展开更多
关键词 LIBS femtosecond laser double pulse signal enhancement
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A novel variable polarity welding power based on high-frequency pulse modulation 被引量:3
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作者 邱灵 杨春利 +2 位作者 范成磊 林三宝 伍昀 《China Welding》 EI CAS 2006年第3期11-15,共5页
A new type of variable polarity welding power modulated with high-frequency pulse current is developed. Series of high-frequency pulse current is superimposed on direct-current-electrode-negative (DCEN), which can i... A new type of variable polarity welding power modulated with high-frequency pulse current is developed. Series of high-frequency pulse current is superimposed on direct-current-electrode-negative (DCEN), which can improve the crystallization process in the weld bead as a result of the electromagnetic force generated by pulse current. Digital signal processor (DSP) is used to realize the closed-loop control of the first inverter, variable polarity output of the second inverter and high-frequency pulse current superposition. 展开更多
关键词 variable polarity welding digital signal processor DSP) high-frequency pulse current pulse current welding
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Digital control of pulsed gas metal arc welding inverter using TMS320LF2407A 被引量:1
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作者 吴开源 黄石生 +1 位作者 李星林 吴水锋 《China Welding》 EI CAS 2008年第1期75-80,共6页
A digital control of pulsed gas metal arc welding inverter was proposed. A control system consisting of analogue parts was replaced with a new digital control implemented in a TMS320LF2407A DSP chip. The design and co... A digital control of pulsed gas metal arc welding inverter was proposed. A control system consisting of analogue parts was replaced with a new digital control implemented in a TMS320LF2407A DSP chip. The design and constructional features of the whole digital control were presented. The resources of the DSP chip were efficiently utilized and the circuits are very concise, which can enhance the stability and reliability of welding inverter. Experimental results demonstrate that the developed digital control has the ability to accomplish the excellent pulsed gas metal arc welding process and the merits of the developed digital control are stable welding process, little spatter and perfect weld appearance. 展开更多
关键词 pulsed gas metal arc welding inverter digital control digital signal processor TMS320LF2407A
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