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Inertia Match of a 3-RRR Reconfigurable Planar Parallel Manipulator

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Chinese Journal of Mechanical Engineering 2009年第6期22卷 791-799页

作者： SHAO Zhufeng TANG xiaoqiang chen Xu WANG Liping Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

Inertia match of the parallel manipulator means the ratio of the inertial load of the parallel manipulator converted to each actuator shaft and the moment of inertia of the actuator is kept within a reasonable range. Currently there are many studies on parallel manipulators, but few mention inertia parameters and inertia match of parallel manipulators. This paper focuses on the inertia characteristics of the 3-RRR reconfigurable planar parallel manipulator. On the basis of the inverse dynamic formulations deduced with the principle of virtual work, the inertia matrix of the 3-RRR planar parallel manipulator in the actuator space is obtained in algebraic form. Then, by unifying the dimension and averaging diagonal elements of the inertia matrix, the equivalent inertia of the parallel manipulator, which is the inertial load of the parallel manipulator converted to each actuator shaft, is determined. By transforming the inertia problem of the 3-RRR parallel manipulator into that of the serial multi-bar manipulator, the practicality of the equivalent inertia deduced by inverse dynamics is demonstrated. According to the physical meaning of the inertia equation, the manipulator is divided in to three parts. Further analysis is carried out on the contribution of each part to the equivalent inertia and their distributions in the required workspace, revealing that the passive links cannot ignored in calculating the equivalent inertia of the parallel manipulator. Finally, the inertia match for the 3-RRR reconfigurable parallel manipulator under three configurations is accomplished, and reducers are selected. The equivalent inertia calculation and the inertial match results illustrate that the inertia math is a necessary step to the design of the parallel manipulator, and inertia parameters dramatically affect dynamic performances of parallel manipulators. Besides, the equivalent inertia and inertial match principles, proposed in the paper, can be widely applied in the dynamic

关键词： inertia match equivalent inertia inverse dynamics parallel manipulator

The regulation of biothiol-responsive performance and bioimaging application of benzo[c][1,2,5]oxadiazole dyes

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Chinese Chemical Letters 2020年第11期31卷 2891-2896页

作者： Dongyang Li Weijie chen Sheng Hua Liu xiaoqiang chen Jun Yin Key Laboratory of Pesticide and Chemical Biology.Ministry of Education Hubei International Scientific and Technological Cooperation Base of Pesticide and Green SynthesisInternational Joint Research Center for Intelligent Biosensing Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhan 430079China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringJiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing Tech UniversityNanjing 211816China

The different oxidation states of sulphur atom play a significant role on functional *** this work,a aryl-thioether and its sulphone substituted benzo[c][1,2,5]oxadiazole dyes were synthesized and utilized to determine thiol-containing amino *** result of selectivity experiments showed they detected the cysteine and homocysteine under physiological condition with negligible interference from other amino *** comparison to the thioether dye,the sulphone-based dye exhibited much faster response time for Cys and ***,the sulphone restricted its thiol-reactivity and bioimaging performance in living *** reducing the oxidation state of sulphur atom,we amazedly found that the sulfoxide-based dye still maintained high selectivity ultrafast response time for Cys/Hcy under physiological *** was worth mentioning that it also had high reactivity and good bioimaging performance that sulfone compounds did not have.

关键词： Benzo[c]oxadiazole dye Sulfoxide Sulphone Thiol response

Microprofiles of activated sludge aggregates using microelectrodes in completely autotrophic nitrogen removal over nitrite （CANON） reactor

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Frontiers of Environmental Science & Engineering 2016年第2期10卷 390-398页

作者： Yongtao LV Xuan chen Lei WANG Kai JU xiaoqiang chen Rui MIAO Xudong WANG School of Environmental and Municipal Engineering Xi'an University of Architecture and Technology Xi'an 710055 China College of Environment and Resource Shaanxi University of Science and Technology Xi'an 710021 China

Microsensor measurements and fluorescence in situ hybridization （FISH） analysis were combined to investigate the microbial populations and activities in a laboratory-scale sequencing batch reactor （SBR） for completely autotrophic nitrogen removal over nitrite （CANON）. Fed with synthetic wastewater rich in ammo- nia, the SBR removed 82.54-5.4% ofinfluent nitrogen and a maximum nitrogen-removal rate of 0.52kgN.m 3.d-l was achieved. The FISH analysis revealed that aerobic ammonium-oxidizing bacteria （AerAOB） Nitrosomonas and anaerobic ammonium-oxidizing bacteria （AnAOB） dominated the community. To quantify the microbial activities inside the sludge aggregates, microprofiles were measured using pH, dissolved oxygen （DO）, NH＋, NO＋ and NO3 microelectrodes. In the outer layer of sludge aggregates （0-700 μm）, nitrite-oxidizing bacteria （NOB） showed high activity with 4.1 gmol-cm3＋ h-1 of maximum nitrate production rate under the condition of DO concentration higher than 3.3 mg. L 1. Maximum AerAOB activity was detected in the middle layer （depths around 1700 μm） where DO concentration was 1.1 μg. L-1. In the inner layer （2200-3500μm）, where DO concentration was below 0.9 mg. L-1, AnAOB activity was detected. We thus showed that information obtained from microscopic views can be helpful in optimizing the SBR performance.

关键词： aerobic ammonium-oxidizing bacteria anae-robic ammonium-oxidizing bacteria nitrite-oxidizing bac-teria microelectrodes CANON

Power Quality Disturbance Identification Basing on Adaptive Kalman Filter andMulti-Scale Channel Attention Fusion Convolutional Network

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Energy Engineering 2024年第7期121卷 1865-1882页

作者： Feng Zhao Guangdi Liu xiaoqiang chen Ying Wang School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou730070China

In light of the prevailing issue that the existing convolutional neural network(CNN)power quality disturbance identification method can only extract single-scale features,which leads to a lack of feature information and weak anti-noise performance,a new approach for identifying power quality disturbances based on an adaptive Kalman filter(KF)and multi-scale channel attention(MS-CAM)fused convolutional neural network is *** and composite-disruption signals are generated through *** adaptive maximum likelihood Kalman filter is employed for noise reduction in the initial disturbance signal,and subsequent integration of multi-scale features into the conventional CNN architecture is *** multi-scale features of the signal are captured by convolution kernels of different sizes so that the model can obtain diverse feature *** attention mechanism(ATT)is introduced to adaptively allocate the extracted features,and the features are fused and selected to obtain the new main *** Softmax classifier is employed for the classification of power quality ***,by comparing the recognition accuracy of the convolutional neural network(CNN),the model using the attention mechanism,the bidirectional long-term and short-term memory network(MS-Bi-LSTM),and the multi-scale convolutional neural network(MSCNN)with the attention mechanism with the proposed *** simulation results demonstrate that the proposed method is higher than CNN,MS-Bi-LSTM,and MSCNN,and the overall recognition rate exceeds 99%,and the proposed method has significant classification accuracy and robust classification *** achievement provides a new perspective for further exploration in the field of power quality disturbance classification.

关键词： Power quality disturbance kalman filtering convolutional neural network attention mechanism

Regenerative Braking Energy Recovery System of Metro Train Based on Dual-Mode Power Management

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Energy Engineering 2024年第9期121卷 2585-2601页

作者： Feng Zhao Xiaotong Zhu xiaoqiang chen Ying Wang School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou730070China

In order to fully utilize the regenerative braking energy of metro trains and stabilize the metro DC traction busbar voltage,a hybrid regenerative braking energy recovery system with a dual-mode power management strategy is ***,the construction of the hybrid regenerative braking energy recovery system is ***,based on the power demand of low-voltage load in metro stations,a dual-mode power management strategy is proposed to allocate the reference power of each system according to the different working conditions,and the control methods of each system are ***,the correctness and effectiveness of the dual-mode strategy are verified through simulation,and the proposed braking energy utilization scheme is compared with other singleform utilization *** results illustrate that the hybrid system with the dual-mode strategy can effectively recycle the regenerative braking energy of metro train and inhibit the busbar voltage fluctuation;the proposed braking energy utilization scheme has certain advantages on energy recovery and DC bus voltage stabilization compared with other single-form schemes;the proposed power management strategy can correctly allocate the reference power of each system with a lower construction cost.

关键词： Metro train regenerative braking energy energy feed-back system energy storage system power management

An Adaptive Control Strategy for Energy Storage Interface Converter Based on Analogous Virtual Synchronous Generator

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Energy Engineering 2024年第2期121卷 339-358页

作者： Feng Zhao Jinshuo Zhang xiaoqiang chen Ying Wang School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou730070China

In the DC microgrid,the lack of inertia and damping in power electronic converters results in poor stability of DC bus voltage and low inertia of the DC microgrid during fluctuations in load and photovoltaic *** address this issue,the application of a virtual synchronous generator(VSG)in grid-connected inverters control is referenced and proposes a control strategy called the analogous virtual synchronous generator(AVSG)control strategy for the interface DC/DC converter of the battery in the ***,a flexible parameter adaptive control method is introduced to further enhance the inertial behavior of the AVSG ***,a theoretical analysis is conducted on the various components of the DC microgrid,the structure of analogous virtual synchronous generator,and the control structure’s main parameters related to the DC microgrid’s inertial ***,the voltage change rate tracking coefficient is introduced to adjust the change of the virtual capacitance and damping coefficient flexibility,which further strengthens the inertia trend of the DC ***,a small-signal modeling approach is used to analyze the approximate range of the AVSG’s main parameters ensuring system ***,conduct a simulation analysis by building the model of the DC microgrid system with photovoltaic(PV)and battery energy storage(BES)in MATLAB/*** results from different scenarios have verified that the AVSG control introduces fixed inertia and damping into the droop control of the battery,resulting in a certain level of inertia ***,the additional adaptive control strategy built upon the AVSG control provides better and flexible inertial support for the DC microgrid,further enhances the stability of the DC bus voltage,and has a more positive impact on the battery performance.

关键词： Adaptive control analogous virtual synchronous generator DC/DC converter inertia of DC microgrid DC microgrid with PV and BES battery DC bus voltage

Research on Virtual DC Generator-Based Control Strategy of DCMicrogrid with Photovoltaic and Energy Storage

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Energy Engineering 2023年第6期120卷 1353-1370页

作者： Feng Zhao chengrui Xiao xiaoqiang chen Ying Wang School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou730070China

With the penetration of a large number of photovoltaic power generation units and power electronic converters,the DC microgrid shows low inertia characteristics,which might affect the stable operation of the microgrid in extreme *** order to enhance the“flexible features”of the interface converter connected to the DC bus,a control strategy of DCmicrogrid with photovoltaic and energy storage based on the virtual DC generator(VDCG)is proposed in this *** interface converters of the photovoltaic power generation system and the energy storage system simulates the inertia and damping characteristics of the DC generator to improve the stability of the DC bus *** impedance ratio of DC microgrid was obtained by establishing the small-signal model of photovoltaic power generation system and energy storage system,and the Nyquist curves was applied to analyze the small-signal stability of the ***,the simulation results were verified with MATLAB/*** results show that the proposed control strategy can slow down the fluctuation of bus voltage under the conditions of photovoltaic power fluctuation and load mutation,thus enhancing the system stability.

关键词： DC microgrid with photovoltaic and energy storage virtual DC generator the low inertia characteristics smallsignal model impedance ratio

Automatic SOC Equalization Strategy of Energy Storage Units with DC Microgrid Bus Voltage Support

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Energy Engineering 2024年第2期121卷 439-459页

作者： Jingjing Tian Shenglin Mo Feng Zhao xiaoqiang chen School of Automation&Electrical Engineering Lanzhou Jiaotong UniversityLanzhou730070China Key Laboratory of Opto-Technology and Intelligent Control(Lanzhou Jiaotong University) Ministry of EducationLanzhou730070China

In this paper,an improved sag control strategy based on automatic SOC equalization is proposed to solve the problems of slow SOC equalization and excessive bus voltage fluctuation amplitude and offset caused by load and PV power variations in a stand-alone DC *** strategy includes primary and secondary *** them,the primary control suppresses the DC microgrid voltage fluctuation through the I and II section control,and the secondary control aims to correct the P-U curve of the energy storage system and the PV system,thus reducing the steady-state bus voltage *** simulation results demonstrate that the proposed control strategy effectively achieves SOC balancing and enhances the immunity of bus *** proposed strategy improves the voltage fluctuation suppression ability by approximately 39.4%and 43.1%under the PV power and load power fluctuation conditions,***,the steady-state deviation of the bus voltage,△U_(dc) is only 0.01–0.1 V,ensuring stable operation of the DC microgrid in fluctuating power environments.

关键词： Automatic equalization independent DC microgrid improve droop control secondary control state of charge

Recognition of Hybrid PQ Disturbances Based on Multi-Resolution S-Transform and Decision Tree

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Energy Engineering 2023年第5期120卷 1133-1148页

作者： Feng Zhao Di Liao xiaoqiang chen Ying Wang School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou730070China Key Lab of Opt-Electronic Technology and Intelligent Control of Ministry of Education Lanzhou Jiaotong UniversityLanzhou730070China

Aiming at the problems of multiple types of power quality composite disturbances,strong feature correlation and high recognition error rate,a method of power quality composite disturbances identification based on multiresolution S-transform and decision tree was ***,according to IEEE standard,the signal models of seven single power quality disturbances and 17 combined power quality disturbances are given,and the disturbance waveform samples are generated in ***,in order to improve the recognition accuracy,the adjustment factor is introduced to obtain the controllable time-frequency resolution through multi-resolution S-transform time-frequency domain *** this basis,five disturbance time-frequency domain features are extracted,which quantitatively reflect the characteristics of the analyzed power quality disturbance signal,which is less than the traditional method based on ***,three classifiers such as K-nearest neighbor,support vector machine and decision tree algorithm are used to effectively complete the identification of power quality composite *** results showthat the classification accuracy of decision tree algorithmis higher than that of K-nearest neighbor and support vector ***,the proposed method is compared with other commonly used recognition *** results show that the proposedmethod is effective in terms of detection accuracy,especially for combined PQ interference.

关键词： Hybrid power quality disturbances disturbances recognition multi-resolution S-transform decision tree