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2018 International Conference on Manufacturing Technology, Materials and Chemical Engineering, MTMCE 2018

作者： Li, Yingqi Liu, Changliang School of Control and Computer Engineering North China Electric Power University Baoding Hebei071003 China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University Changping District Beijing102206 China

It is challenging and interesting to establish a precise steam pressure in separator dynamic model of a once-through power plant unit in order to meet large scale load demands from the power grid and the needs of the engineering research. Steam pressure reveals the energy balance of boiler and turbine. This study proposes to establish such a steam pressure in separator mathematical model of a once-through boiler-turbine unit under dry operating conditions. Then the BP neural network model and the RBF neural network model were used to predict the steam pressure in separator, combined with running data. Moreover, in order to improve the performance of the network, the exhaustive method is used to optimize the parameters of the RBF network. After this, to further enhance model performance, the dynamic mathematical model was extended to be the one with different sets of parameters under different load ranges. More importantly, the dynamic model captures the essential dynamic characteristics of the unit. Therefore, the model can be feasible and applicable for simulation analysis and testing control algorithms. © Published under licence by IOP Publishing Ltd.

关键词： Separators

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Fault Diagnosis of Wind Turbine Gearbox Based on Wavelet Transform

Fault Diagnosis of Wind Turbine Gearbox Based on Wavelet Tra...

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2018 International Conference on Manufacturing Technology, Materials and Chemical Engineering, MTMCE 2018

作者： Li, Hao Liu, Changliang School of Control and Computer Engineering North China Electric Power University Baoding Hebei071003 China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University Changping District Beijing102206 China

As a kind of clean and renewable energy, wind energy is attracting more and more attention from all over the world. But the development of wind power is always hindered by the failure of downtime. The gearbox of wind power unit is one of the components with the highest failure rate in the whole wind turbine. Therefore, it is of great significance to study the fault diagnosis of gearbox in wind turbine. This paper first introduces the mathematical principle of wavelet analysis, and takes Matlab as an experimental platform to analyze and deal with the pitting fault data of a fan gearbox, and identifies the fault frequency by wavelet packet energy method, and diagnoses the type of failure. Finally, the experimental results are compared with other methods to deal with the data. Through the research in this paper, we can see that the data processing method based on wavelet analysis is simple and practical, especially in the engineering field represented by gearbox fault diagnosis. © Published under licence by IOP Publishing Ltd.

关键词： Wind power

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Soft-sensing of NOx content in power Station based on BP Neural Network, RBF Neural Network and PCA-RBF Neural Network

Soft-sensing of NOx content in power Station based on BP Neu...

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2018 International Conference on Manufacturing Technology, Materials and Chemical Engineering, MTMCE 2018

作者： Hu, Peitao Changliang, Liu School of Control and Computer Engineering North China Electric Power University Baoding Hebei071003 China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University Changping District Beijing102206 China

The timely and accurate measurement of the NOx content of the power plant denitrification system is very important for the precise regulation of the amount of ammonia and the control of the NOx emission. In this paper, we use 660MW coal-fired units as the research object. Combined with consideration of the poor accuracy and hysteresis of NOx measurement, the prediction models are established respectively by using RBF neural network, BP neural network and PCA-RBF neural network. The PCA-RBF model is based on principal component analysis (PCA) and RBF neural network. In order to improve the accuracy of the NOx soft-sensing model, this paper simplifies the sample model by optimizing the data samples, reducing the redundant information, and using dynamic neural network to achieve more accurate and faster training model. The results show that RBF neural network is superior to BP neural network in prediction accuracy and speed, while the improved and optimized PCA-RBF model has better prediction accuracy than the RBF neural network model. At the same time, this paper provides a theoretical basis for the real-time and accurate measurement of NOx content in power station, and provides some reference for improving the measurement and control of NOx in the actual production process. © Published under licence by IOP Publishing Ltd.

关键词： Principal component analysis

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Encoding Space to Count Multi-Targets with Multiplexed Binary Infrared Sensors

Encoding Space to Count Multi-Targets with Multiplexed Binar...

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International Conference on Mobile Ad-hoc and Sensor Networks, MSN

作者： Longxiang Luo Yang Xiao Wei Liang Key Laboratory of Networked Control System Shenyang Institute of Automation Chinese Academy of Sciences Shenyang State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang Chinese Academy of Sciences Institutes for Robotics and Intelligent Manufacturing Shenyang China University of Chinese Academy of Sciences Beijing China Department of Computer Science The University of Alabama Tuscaloosa AL USA

ISBN: (数字)9781728152127

ISBN: (纸本)9781728152134

Recently, many researchers multiplex binary infrared sensors in object tracking, habitat monitoring, and atypical behavior detection. Due to the binary digit output of binary sensors, multiplex binary sensors may lead to count the wrong number of targets when three or more targets present in the field of interest (FOI). We call this as the invisible targets' problem. To enhance the sensing results of sensors, a reference structure tomography technique is used to segment and code the FOI by modulating the sensing view of sensors. In this paper, we propose a subregion coding method to count targets moving in the FOI. Hexagon modulators are designed to make their projections segment the FOI into hexagon cells. We also propose a signature construct scheme to code cells and a encoder to count the number of targets in the FOI. Experiment results show that the accuracy to correctly count targets of our method is around 90% which is much better than 45% of a conventional method.

关键词： Modulation Monitoring Shape Sensor systems Encoding Intelligent sensors

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arXiv

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arXiv 2020年

作者： Li, Jiashuo Zhou, Sili Wei, Wendong Qi, Jianchuan Li, Yumeng Chen, Bin Zhang, Ning Guan, Dabo Qian, Haoqi Wu, Xiaohui Miao, Jiawen Chen, Long Liang, Sai Feng, Kuishuang Institute of Blue and Green Development Shandong University Weihai264209 State Key Laboratory of Coal Combustion School of Energy and Power Engineering Huazhong University of Science and Technology Wuhan430074 China School of International and Public Affairs Shanghai Jiao Tong University Shanghai200030 China State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Beijing Normal University Beijing100875 China Laboratory of Anthropogenic Systems Ecology College of Engineering Peking University Beijing100871 China Department of Earth System Science Tsinghua University Beijing100871 China Institute for Global Public Policy Fudan University Shanghai200433 China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and Technology Shanghai200093 China Key Laboratory of Geographic Information Science Ministry of Education School of Geographic Sciences East China Normal University Shanghai200241 China

China has implemented retrofitting measures in coal-fired power plants (CFPPs) to reduce air pollution through small unit shutdown (SUS), the installation of air pollution control devices (APCDs) and power generation efficiency (PGE) improvement. The reductions in highly toxic Hg emissions and their related health impacts by these measures have not been well studied. To refine mitigation options, we evaluated the health benefits of reduced Hg emissions via retrofitting measures during China's 12th Five-Year Plan by combining plant-level Hg emission inventories with the China Hg Risk Source-Tracking Model. We found that the measures reduced Hg emissions by 23.5 tons (approximately 1/5 of that from CFPPs in 2010), preventing 0.0021 points of per-foetus intelligence quotient (IQ) decrements and 114 deaths from fatal heart attacks. These benefits were dominated by CFPP shutdowns and APCD installations. Provincial health benefits were largely attributable to Hg reductions in other regions. We also demonstrated the necessity of considering human health impacts, rather than just Hg emission reductions, in selecting Hg control devices. This study also suggests that Hg control strategies should consider various factors, such as CFPP locations, population densities and trade-offs between reductions of total Hg (THg) and Hg2+. Copyright © 2020, The Authors. All rights reserved.

关键词： Fossil fuel power plants

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control of Nonlinear Constrained Ultra-Supercritical Boiler–Turbine Units Using Offset-Free Output-Feedback Stable MPC

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IFAC-PapersOnLine 2018年第28期51卷 155-160页

作者： Chen, Chen Pan, Lei Shen, Jiong Lee, Kwang Y. Zhang, Fan Sun, Li Wu, Xiao Zhang, Junli Xue, Wenchao Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education Southeast University Nanjing210096 China Department of Electrical and Computer Engineering Baylor University One Bear Place #97356 WacoTX76798-7356 United States State Key Lab of Power System Department of Energy and Power Engineering Tsinghua University Beijing100084 China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China

It is extremely challenging to control ultra-supercritical boiler–turbine unit on account of its nonlinearity, coupling among multi-variables, hard input constraints, and unknown disturbances. An offset-free output-feedback stable model predictive control (MPC) (OFOF-SMPC) for nonlinear constrained ultra-supercritical boiler-turbine units is investigated. It is shown that the OFOF-SMPC is composed of a disturbance and state observer, a steady-state target calculator as well as a stable MPC, which can remove unknown disturbances from output channels and ensure the stability of the closed-loop system with input constraints. Simulation results demonstrate the effectiveness of the proposed algorithm. © 2018

关键词： Feedback

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Future Development Trend of Multimedia Network 2

Future Development Trend of Multimedia Network

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2018 2nd Annual International Conference on Cloud Technology and Communication Engineering, CTCE 2018

作者： Huang, Li Zhang, Kai Hu, Wei Li, Chengcheng College of Computer Science and Technology Wuhan University of Science and Technology Wuhan Hubei430081 China Hubei Province Key Laboratory of Intelligent Information Processing and Real-time Industrial System Wuhan University of Science and Technology Wuhan Hubei430081 China Key Laboratory of Metallurgical Equipment and Control Technology Ministry of Education Wuhan University of Science and Technology Wuhan Hubei430081 China

With the rapid development of computer network, multimedia technology has gradually spread throughout all aspects of people's life. This article, based on the concept and characteristics of multimedia, expounds the application of multimedia technology and the trend of future development. It makes a heavy analysis of multimedia teaching and analyses the meaning and advantage of multimedia teaching. © Published under licence by IOP Publishing Ltd.

关键词： Multimedia systems

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Mitigate the obstructing effect of vehicles on the propagation of VANETs safety-related information

Mitigate the obstructing effect of vehicles on the propagati...

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作者： Huang, Rui Wu, Jing Long, Chengnian Zhu, Yanmin Li, Bo Lin, Yi-Bing Department of Automation Shanghai Jiao Tong University Key Laboratory of System Control and Information Processing Ministry of Education of China Shanghai200240 China Department of Computer Science School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University Shanghai200240 China Department of Computer Science and Engineering The Hong Kong University of Science and Technology Hong Kong China Department of Computer Science and Information Engineering National Chiao Tung University Taiwan

As physical obstacles, vehicles have significant impacts on the efficient propagations of safety-related information in vehicular ad hoc networks (VANETs) by frequently obstructing the LOS links between transmitters and receivers. Obstructing effect will diminish the effective coverage of safety-related information and incur severe impact on road safety. However, this impact has not been addressed effectively. In this paper, we first present the definition of broadcast efficiency as the metric for quantizing the obstructing effect. We investigate the optimization issue for mitigating the impact of obstructing effect on the propagation of safety-related information and propose a graph theory-based optimization algorithm. For a distributed implementation of this optimization in VANETs, we further propose the maximum broadcast efficiency relaying (MBER) algorithm. MBER maximizes the effective coverage of information, meanwhile, meets delay and reliability constraints by incorporating broadcast efficiency and propagation distance in relay contention. Simulation results demonstrate that MBER promotes the effective coverage of safety-related information in VANETs with varying vehicular distribution. © 1967-2012 IEEE.

关键词： Vehicular ad hoc networks

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Research of Optimal Load Dispatch in Power Plant Prevents Frequent Coal Mills Operation based on Speediness 2

Research of Optimal Load Dispatch in Power Plant Prevents Fr...

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2017 IEEE 2nd Information Technology, Networking, Electronic and Automation control Conference (ITNEC 2017)

作者： Li Qing Gao Yao-kui Xv Hao Control and Computer Engineering Beijing Key Laboratory of New Technology and System on Measuring and Control for Industrial Process North China Electric Power University

ISBN: (纸本)9781509064151;9781509064144

In order to satisfy the rapid load adjustment requirements of coal-fired units in the situation of alternate electrical power system, the optimal load dispatch in power plant prevents frequent coal mills operation based on speediness is studied in this paper. Firstly, the mathematical formulation of PPLD with POZs based on speediness is presented, and then strategy of POZs constraints and improved GA-TS algorithm to find the optimal solution are introduced. Finally, through simulation the effectiveness of the mathematical formulation of PPLD with POZs based on speediness is tested. The simulation result show: when the load is distributed with the economy and speediness as target separately, the distribution results are significantly different, and the load adjustment time with the aim of speediness is obviously shorter than that of economy. It shows that the optimal load dispatch in power plants based on speediness is an effective control strategy for the rapid load adjustment of units, which can contribute to the further improvement of the operating flexibility of coal-fired units in the new energy power system situation.

关键词： optimal load dispatch in power plant prohibited operating zones improved GA-TS algorithm speediness economy

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Standard Analysis for Transfer Delay in CTCS-3

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Chinese Journal of Electronics 2017年第5期26卷 1057-1063页

作者： CAO Yuan MA Lianchuan XIAO Shuo ZHANG Xia XU Wei National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University School of Computer Sciences and Technology China University of Mining & Technology National Mobile Communications Research Lab. Southeast University

According to the standard for the GSM for railway(GSM-R) wireless systems in China train control system level 3(CTCS-3),the control data transfer delay should be no larger than 500 ms with greater than99% *** of both non-redundant networks and intercross redundant networks and cases of single Mobile terminals(MTs) and redundant MTs on one train are considered,and the corresponding vehicle-ground communication models,delay models,and fault models are *** simulation results confirm that the transfer delay can meet the standard requirements under all *** particular,the probability is greater than 99.996% for redundant MTs and networks,and the standard of transfer delay in CTCS-3 will be improved inevitably.

关键词： China train control system level 3(CTCS-3) GSM for railway(GSM-R) Data transfer delay Deterministic and stochastic petri net(DSPN)

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