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Dynamic modelling and small signal analysis of push-pull bidirectional DC-DC converter

Computer Modelling and New Technologies 2014年第10期18卷 14-18页

作者： Zhang, Hongjuan Quan, Long Gao, Yan Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan China

Bidirectional DC-DC converter can not only act as a contact bridge between two different voltage levels systems, but also can achieve the energy flow in both directions. However, due to the operating characteristics of the active switch and diode in the converter, thereby the inverter becomes a strong nonlinear circuit. In light of this, the push-pull bidirectional DC-DC converter is designed and the method of state space small signal analysis is proposed. First of all, the state-space equations of the converter are established. Then each variable of inverter circuit is averaged in a switching cycle to eliminate the influence of the switching ripple. The respective average variable expressions are decomposed into the DC component and AC small signal component. After the DC component of the signal is eliminated, the expression of the AC small signal component is obtained, to achieve the purpose of separating the small signal. Finally, the expression of small signal component is linearized, thereby the nonlinear system is approximated the DC operating point. This study will provide the theoretical foundation ready for the analysis and design of converter controller.

关键词： Linearization

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Indefinite metacavities coupled to a mirror:bound states in the continuum with anomalous resonance scaling

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Photonics Research 2024年第3期12卷 598-607页

作者： QIANG ZHANG PEIXIANG LI ZHIYUAN GU SHAODING LIU ZEJUN DUAN College of Electronic Information and Optical Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China

Indefinite metacavities(IMCs)made of hyperbolic metamaterials show great advantages in terms of extremely small mode volume due to large wave vectors endowed by the unique hyperbolic ***,quality(Q)factors of IMCs are limited by Ohmic loss of metals and radiative loss of leaked *** the fact that Ohmic loss of metals is inevitable in IMCs,the radiative loss can be further suppressed by leakage *** we propose a mirror coupled IMC structure which is able to operate at Fabry–Pérot bound states in the continuum(BICs)while the hyperbolic nature of IMCs is *** the BIC point,the radiative loss of magnetic dipolar cavity modes in IMCs is completely absent,resulting in a considerably increased Q factor(>90).Deviating from the BIC point,perfect absorption bands(>0.99)along with a strong near-field intensity enhancement(>1.8×10^(4))appear when the condition of critical coupling is almost *** proposed BICs are robust to the geometry and material composition of IMCs and anomalous scaling law of resonance is verified during the tuning of optical *** also demonstrate that the Purcell effect of the structure can be significantly improved under BIC and quasi-BIC regimes due to the further enhanced Q factor to mode volume *** results provide a new train of thought to design ultra-small optical nanocavities that may find many applications benefitting from strong light–matter interactions.

关键词： hyperbolic mirror definite

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Research on the performance of hydraulic excavator with pump and valve combined separate meter in and meter out circuits

Research on the performance of hydraulic excavator with pump...

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International Conference on Fluid Power and Mechatronics (FPM)

作者： Lei Ge Zhixin Dong Weinan Huang Long Quan Jing Yang Wenyong Li Taiyuan University of Technology Key Lab of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan China

ISBN: (纸本)9781479987719

Conventional hydraulic actuator is controlled by mechanically connected orifices valve. The controllability of this method is poor and the energy consumption is huge especially under the over-running condition. So a novel system configuration of the hydraulic excavator is presented to improve the problem mentioned above, in which boom cylinder, stick cylinder and swing motor are controlled with separate meter in and meter out technology, bucket cylinder and travel motors are controlled with conventional valves. Firstly, the paper provides a comprehensive review on the development of the separate meter in and meter out technology. Then the principles of load sensing system and SMISMO system applied on the excavator are illustrated though two diagram to show the difference of the two systems. And then a virtual prototype based on the real physical structures is established, which consists of the hydraulic excavator mechanical structure with multi-body dynamics and electro-hydraulic system. The model is verified by the statics and dynamics experiments. Then the dynamic, static performances as well as the energy consumption characteristics of the boom, arm and swing actuators are investigated under the condition of load sensing hydraulic system and the proposed system using the virtual prototype. The control strategy of the actuators is formulated according to their load condition and operation characteristics also based on the detailed analysis. After that, the physical prototype based on the proposed configuration system is established and its performance is tested. The experimental results show that the accuracy of the virtual prototype is validated; the proposed configuration system can significantly decreases the pressure losses through the valve and improve the energy efficiency of the machine; the pressure shocks within hydraulic actuators is decreased as well, thus the stationarity of the whole machine is improved accordingly.

关键词： Valves Actuators Prototypes Energy consumption Cavity resonators Load modeling

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Abnormal Visible Luminescence Mechanism of Tb3+-Yb3+ Codoped SiO2-Al2O3-CaF2 Glass Studied by Time-Resolved Spectra

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中国物理快报（英文版） 2014年第8期31卷 151-154页

作者： DUAN Qian-Qian ZHAO Hua ZHANG Zhi-Guo JIAN Ao-Qun SANG Sheng-Bo ZHANG Wen-Dong Micro and Nano-system Research Center College of Information Engineering Taiyuan University of TechnologyTaiyuan 030024 Key Laboratory of Advanced Transducers and Intelligent Control(Shanxi Province and Ministry of Education) Taiyuan University of Technology Taiyuan 030024 School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 Condensed Matter Science and Technology Institute Harbin Institute of Technology Harbin 150001

The upconversion energy transfer mechanism in Tb3+-Yb3+ co-doped SiO2-Al2O3-CaF2 glass is investigated by time-resolved spectra. The effect of donor ion Yb3+ is involved in the dynamic decay behavior of acceptor ion Tb3+, which provides direct proof for the energy transfer from Yb3+ to Tb3+. The pump power dependence curves show that the upconversion luminescence is a two-photon process. The measured decay curves of the 5D4 state (Tb3+) contain two parts: a slow decay process corresponding to its radiation, and a fast one with a decay parameter approximately twice the lifetime of the 2F5/2 state (Yb3+). The fast decay process is contradictory to the generally accepted cooperative sensitization upconversion rate equation model. Since the effect of the host environmental is excluded by comparative experiments, we believe that there should be another energy transfer mechanism in Tb3+-Yb3+ co-doped SiO2-Al2O3-CaF2 glass in addition to the cooperative sensitization process.

关键词： Silica

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The power supply design software model for mine based on VBA technology

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Computer Modelling and New Technologies 2014年第8期18卷 127-130页

作者： Jin, Baoquan Hao, Xiaohui Zhang, Hongjuan Gao, Yan Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan China

Coal mine power supply system is increasingly complex, resulting in difficulties for power computing and tuning. A software design program is proposed by using VBA development tools embedded in AutoCAD secondary development, adopt object-oriented program, ActiveX automation technology and visual programming techniques to achieve human-computer interface and database interaction, design one of the mine power supply design software with function mapping, statistical calculations, protection setting, design reports automatically output, data maintenance. The study shows that the software can greatly simplify the power supply design process, improve efficiency, and can effectively improve the coal mine management level.

关键词： Software design

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Transient Flow Field Characteristic Analysis of Poppet Valve Based on Dynamic Mesh 6DOF Technique

Transient Flow Field Characteristic Analysis of Poppet Valve...

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2015 International Conference on Fluid Power and Mechatronics

作者： Guo Xiao-xia Huang Jia-hai Quan Long Wang Sheng-guo Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of Technology

In the fluid engineering, many projects involve movement and deformation of the boundary, but it is difficult to describe them by a simple algebraic expression because the movement of the boundary is determined by the force of hydraulic pressure, torque and other force which work together on the boundary. However, the previous numerical analyses are limited to the steady method or directly giving a speed to the spool which is difficult to actually simulate the movement of the spool. This paper developed a 6DOF model of a threedimensional poppet valve to stimulate the transient flow field in the opening process by means of computational fluid dynamics software—Fluent. The movement of the spool is decided by fluid force which exert on it and its gravity. By comparing numerical simulation results of the valve displacement, pressure of the control chamber and the inlet and outlet flow rate of poppet valve with the experimental results, the numerical results are the same as the experimental results. So the method that the paper proposed is feasible and more truly to simulate the flow state in the opening process of hydraulic valve. And on this basis, the pressure field, velocity field and flow regime are researched when poppet valve reaches steady state, which provides an important theoretical basis for further research on hydraulic valve performance.

关键词： poppet valve numerical calculation Dynamic Mesh Fluent

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Recent progress in the preparation of AuNPs-P DMS composite membranes

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Journal of Measurement Science and Instrumentation 2013年第2期4卷 199-204页

作者：马文哲桑胜波张文栋胡杰李朋伟李刚 MicroNano System Research Center Taiyuan Unive rsity of Technology Key Laboratory of Advanced Transducers and Intelligent Control System Shanxi Province and Ministry of Education

Gold nanoparticles-dimethylsiloxane(AuNPs-PDMS) membrane is a novel composite material in biochemical technology an d micro-electro-mechanical system(MEMS) *** is widely used in biomed ici ne,biochemical detection and en vironmental protection due to its biocompatibility,elasticity and electric char *** this paper,the characteristics of the composite membrane were d escribed,and four methods for fabricating AuNPs-PDMS composite membranes were reviewed in ***,the advantages and disadvantages of the four method s were summarized,and the present problems and future researches were proposed.

关键词： gold nanoparticles (AuNPs) polydimethylsiloxane (PDMS) composite membrane

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Performance Improvement of Raman Distributed Temperature system by Using Noise Suppression

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Photonic Sensors 2018年第2期8卷 103-113页

作者： Jian LI Yunting LI Mingjiang ZHANG Yi LIU Jianzhong ZHANG Baoqiang YAN Dong WANG Baoquan JIN Key Laboratory of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan University of Technology Taiyuan 030024 China College of Physics and Optoelectronics Institute of Optoelectronic Engineering Taiyuan University of Technology Taiyuan 030024 China

In Raman distributed temperature system, the key factor for performance improvement is noise suppression, which seriously affects the sensing distance and temperature accuracy. Therefore, we propose and experimentally demonstrate dynamic noise difference algorithm and wavelet transform modulus maximum （WTMM） to de-noising Raman anti-Stokes signal. Experimental results show that the sensing distance can increase from 3 kin to 11.5 km and the temperature accuracy increases to 1.58 ℃ at the sensing distance of 10.4kin.

关键词： Optical fiber sensors Raman scattering noise suppression wavelet transform modulus maximum

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Simultaneous Strain and Temperature Measurement Based on Chaotic Brillouin Optical Correlation-Domain Analysis in Large-Effective-Area Fibers

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Photonic Sensors 2021年第4期11卷 377-386页

作者： Xiaocheng ZHANG Shuangshuang LIU Jianzhong ZHANG Lijun QIAO Tao WANG Shaohua GAO Mingjiang ZHANG Key Laboratory of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan University of TechnologyTaiyuan 030024China College of Physics and Optoelectronics Institute of Optoelectronic EngineeringTaiyuan University of TechnologyTaiyuan 030024China

Chaotic Brillouin optical correlation domain analysis(BOCDA)has been proposed and experimentally demonstrated with the advantage of high spatial ***,it faces the same issue of the temperature and strain *** this paper,the simultaneous measurement of temperature and strain can be preliminarily achieved by analyzing the two Brillouin frequencies of the chaotic laser in a large-effective-area fiber(LEAF).A temperature resolution of 1℃ and a strain resolution of 20μξ can be obtained with a spatial resolution of *** actual temperature and strain measurement errors are 0.37℃ and 10μξ,respectively,which are within the maximum measurement errors.

关键词： Brillouin scattering simultaneous strain and temperature measurement chaotic laser BOCDA LEAF

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Anti-disturbance proportional integral attitude control and stabilization of rolling hydraulic position system

Anti-disturbance proportional integral attitude control and ...

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作者： Gong, Lishuang Jin, Baoquan Zhang, Hongjuan Gao, Yan Wang, Dong Wang, Yu Key Laboratory of Advanced Transducers and Intelligent Control Systems Ministry of Education Taiyuan University of Technology Taiyuan030024 China College of Electrical Engineering Taiyuan University of Technology Taiyuan China

Disturbance rejection performance for rolling hydraulic position control system has always been a knotty issue. To guarantee the transient performance and improve disturbance rejection performance of the rolling hydraulic position control system, a compound controller, composed of a feedforward controller part based on proportional integral laws and a compensation part based on disturbance observer, is designed and investigated. In this article, a detailed analysis and design principles of the composite controller are provided. Additionally, stability analysis of the controller is proved using Lyapunov function adapted to the system. Finally, a rigorous analysis of the disturbance rejection performance is given with consideration of both instantaneous disturbances and low-frequency disturbances. For single pulse disturbance, the maximum error is reduced from 3.5% to 0.6%. Furthermore, for more complicated disturbance, sinusoidal disturbance is lower than 50 Hz, disturbance rejection performance decreases with increasing frequency and maximum error is reduced from 5.4% to 1.6%. The test results demonstrate that for single pulse disturbance, the maximum error is reduced from 4.12% to 0.64%. Furthermore, for more complicated disturbance, sinusoidal disturbance is lower than 50 Hz, disturbance rejection performance decreases with increasing frequency and maximum error is reduced from 2.71% to 0.70%. Both simulation and experiment results demonstrate that the proposed method possesses a better disturbance rejection performance than the proportional integral method. © Institution of Mechanical Engineers.

关键词： controllers

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