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Primary Frequency Control Ability Evaluation of Valve Opening in Thermal Power Units Based on Artificial Neural Network

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Journal of Thermal Science 2020年第3期29卷 576-586页

作者： liao jinlong LUO Zhihao YIN Feng CHEN Bo SHENG Deren LI Wei YU Zitao Institute of Thermal Science and Power Systems Zhejiang UniversityHangzhou 310027China Electric Power Research Institute of State Grid Zhejiang Electric Power Co.Ltd Hangzhou 310027China

With the development of new energy,the primary frequency control(PFC)is becoming more and more important and *** improve the reliability of the PFC,an evaluation method of primary frequency control ability(PFCA)was ***,based on the coupling model of the coordinated control system(CCS)and digital electro-hydraulic control system(DEH),principle and control mode of the PFC were introduced in *** simulation results showed that the PFC of the CCS and DEH was the most effective control ***,the analysis of the CCS model and variable condition revealed the internal relationship among main steam pressure,valve opening and *** term of this,the radial basis function(RBF)neural network was established to estimate the *** the simulation curves fit well with the actual curves,the accuracy of the coupling model was *** this basis,simulation data was produced by coupling model to verify the proposed evaluation *** low predication error of main steam pressure,power and the PFCA indicated that the method was *** addition,the actual data obtained from historical operation data were used to estimate the PFCA accurately,which was the strongest evidence for this method.

关键词： primary frequency control valve opening main steam pressure thermal power unit artificial neural network evaluation

Sound absorption characteristics of underwater flexible micro-perforated sound absorption structures

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Chinese Journal of Acoustics 2020年第4期39卷 512-525页

作者： HOU Jiuxiao ZHU Haichao liao jinlong YUAN Suwei National Key Laborutory on Ship Vibration&Noise Institute of Noise&VibrationNaval University of EngineeringWuhan 430033

A mathematical model for the micro-perforated panel in water medium is established using mode superposition method,and an equivalent circuit model is acquired based on electro-acoustic analogy *** of the flexible micro-perforated panel(FMPP) and the flexible back panel(FBP) on normal incidence sound absorption coefficient are *** micro-perforated panel in air medium,the underwater micro-perforated panel cannot achieve any satisfactory sound absorption effect due to insufficient structural *** this end,a strengthened micro-perforated sound absorption structure is *** results are verified in a water-filled impedance *** the range from 20 Hz to 2,000 Hz the average absorption coefficient of the strengthened flexible micro-perforated panel are improved *** absorption coefficient curve gradually approaches rigid micro-perforated panel as the bending stiffness *** flexible back panel can reduce the resonance frequency of the absorption curve and improve the low-frequency sound absorption performance.

关键词： absorption sound underwater

Transmission loss of a flexible micro-perforated muffler with a flexible back cavity for water-filled pipelines

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Chinese Journal of Acoustics 2021年第1期40卷 31-45页

作者： HOU Jiuxiao ZHU Haichao YUAN Suwei liao jinlong National Key Laboratory on Ship Vibration&Noise Institute of Noise&VibrationNaval University of EngineeringWuhan 430033

To reduce low-frequency noise of the water-filled pipeline system,a compact flexible micro-perforated muffler with a flexible back cavity(FMPMFBC) is *** flexible pipe wall is made of a rubber-cord composite material.A numerical solution for the transmission loss is ***,the flexible micro-perforated panel(FMPP) is equivalent to a flexible porous material based on Biot-Allard porous-elastic ***,a periodic structural unit of the aramid fabric cloth is established with the two-scale method,and the equivalent stiffness matrix is ***,a multi-layer composite model for the flexible pipe wall is constructed according to the lamination *** with the internal sound field,the transmission loss of the FMPMFBC is *** a water-filled impedance tube,the transmission loss curves of the FMPMFBC prototypes are measured with the two source-location method,and compared with those of a flexible micro-perforated muffler with a rigid back cavity(FMPMRBC)and an expansion *** results are experimentally *** FMPMFBC is a hybrid muffler combining reflection with dissipation,capable of attenuating broadband lowfrequency *** transmission loss of prototype B2 in the frequency bands of [40 300] Hz and [40 1200] Hz is 36 dB and 30 dB,respectively,while the transmission loss of the same-sized expansion muffler in the corresponding frequency bands is 7 dB and 11 dB,respectively.

关键词： composite cavity perforated

Calculation and analysis for acoustic radiation mode of strong and weak plate-cavity coupling systems

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Chinese Journal of Acoustics 2023年第2期42卷 220-234页

作者： liao jinlong ZHU Haichao HOU Jiuxiao YUAN Suwei National Key Laboratory on Ship Vibration and Noise Institute of Noise and VibrationNaval University of EngineeringWuhan 430033

A method based on the energy principle is proposed for calculating the acoustic radiation mode of plate-cavity coupling *** relationship between the acoustic pressure mode amplitude vector and the structural mode amplitude vector is constructed according to the kinetics equations based on the energy *** acoustic radiation mode of plate-cavity coupling systems is derived by expressing the acoustic potential energy as a quadratic form of the structural mode amplitude *** proposed method bridged the gap in previous theories concerning plate-cavity coupling systems with impedance walls and strong structuralacoustic *** correctness and effectiveness of the proposed method are verified by numerical *** that basis,the effects of changes in wall surface settings and structuralacoustic coupling conditions on the characteristics of acoustic radiation mode are *** results show that the acoustic radiation mode radiation efficiency curve peaks at the acoustic modal frequency,whose amplitude is reduced by using impedance ***,a lower impedance has more significant amplitude attenuation ***,the amplitude of the acoustic potential energy curve at the peak radiation efficiency frequency decreases;under strong coupling conditions,the acoustic potential energy response in the low-frequency band is mainly excited by the structural mode,resulting in a higher response peak density and lower *** the same bandwidth,the acoustic radiation mode in the low-frequency range has fewer radiation efficiency peaks and higher peak frequencies.

关键词： coupling plate impedance

Estimating the mixing matrix by using less sparsity

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Progress in Natural Science:Materials International 2009年第8期19卷 1027-1031页

作者： Guoxu Zhou a, Zuyuan Yang a, Xiaoxin liao b, jinlong Zhanga a School of Electrics & Information Engineering, South China University of Technology, Guangzhou 510641, China b Department of Control Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China School of Electrics & Information Engineering South China University of Technology Guangzhou 510641 China Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

In this paper, the nonlinear projection and column masking (NPCM) algorithm is proposed to estimate the mixing matrix for blind source separation. It preserves the samples which are close to the interested direction while suppressing the rest. Compared with the existing approaches, NPCM works efficiently even if the sources are less sparse (i.e., they are not strictly sparse). Finally, we show that NPCM provides considerably accurate estimation of the mixing matrix by simulations.

关键词： Sparse component analysis Blind source separation Particle swarm optimization

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结构-声强耦合腔振声响应预报研究

振动与冲击 2022年第5期41卷 83-89,140页

作者：廖金龙朱海潮侯九霄海军工程大学振动与噪声研究所船舶振动噪声重点实验室武汉430033

针对结构-声强耦合腔在边界激励下的响应预报问题,提出了一种基于能量原理的耦合系统响应计算方法。该方法从能量原理出发得到结构-声耦合腔拉格朗日函数形式的动力学方程,根据Rayleigh-Ritz法选择Legendre多项式级数分别将结构位移函... 详细信息

针对结构-声强耦合腔在边界激励下的响应预报问题,提出了一种基于能量原理的耦合系统响应计算方法。该方法从能量原理出发得到结构-声耦合腔拉格朗日函数形式的动力学方程,根据Rayleigh-Ritz法选择Legendre多项式级数分别将结构位移函数和声场声压函数展开,代入动力学方程并求解得到耦合腔的结构振动和声场声压响应。由于Legendre多项式满足L^(2)内积正交性,简化了方程中高重积分项,计算效率大大提升。以充水矩形腔为例,通过与已有研究、有限元结果对比验证了该方法的正确性。并分析了结构边界条件,背腔深度对系统响应的影响,结果表明:结构边界由强约束过渡到弱约束和背腔深度的减小都会导致响应峰值频率向低频偏移,同时背腔深度的减小还会导致由结构传递至声场的能量增加。

关键词：结构-声强耦合响应预报能量原理多项式级数

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考虑一次调频能力的火电机组负荷优化分配

中国电机工程学报 2018年第S1期38卷 168-174页

作者：廖金龙陈波丁宁俞自涛李蔚盛德仁浙江大学热工与动力系统研究所浙江省杭州市310027 国网浙江省电力有限公司电力科学研究院浙江省杭州市310027

机组调峰深度与调峰能力在一定程度上不可兼得,为使电力系统运行经济的同时具备足够的调峰裕度,提出了考虑一次调频能力的机组负荷优化分配模型,引入新型正弦余弦算法(sine cosine algorithm,SCA)求解。以某电厂4台机组为例验证模型的... 详细信息

机组调峰深度与调峰能力在一定程度上不可兼得,为使电力系统运行经济的同时具备足够的调峰裕度,提出了考虑一次调频能力的机组负荷优化分配模型,引入新型正弦余弦算法(sine cosine algorithm,SCA)求解。以某电厂4台机组为例验证模型的有效性,分别采用SCA和遗传算法(genetic algorithm, GA)寻优计算并与自动发电控制(automatic generation control,AGC)指令对比,结果表明SCA的最优解比GA精度更高,而且新模型既能保证足够的一次调频备用容量又有更高经济性。通过仿真得出不同负荷率最优经济成本与一次调频备用容量的关系曲线,总结了此规律对负荷优化分配的指导意义。最后仿真研究低负荷率时的负荷分配,结果表明模型会优先选取经济性较好的机组进行深度调峰以保证整体最佳经济性。

关键词：一次调频能力负荷优化分配深度调峰正弦余弦算法经济性分析

基于不同谐振腔结构的有机微腔激光器的研究进展(特邀)

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光子学报 2024年第5期53卷 80-98页

作者：朱金龙付红兵廖清首都师范大学化学系光功能材料与器件北京市重点实验室北京100048

有机微腔激光器利用有机增益材料和微腔结构的优点,在先进的光学领域中取得了巨大的发展,具有广泛的应用前景。有机微腔激光器通过对增益材料和谐振腔的调控,实现对激光的频率、横向分布特性及模式选择等进行选择性输出。本文对近年来... 详细信息

有机微腔激光器利用有机增益材料和微腔结构的优点,在先进的光学领域中取得了巨大的发展,具有广泛的应用前景。有机微腔激光器通过对增益材料和谐振腔的调控,实现对激光的频率、横向分布特性及模式选择等进行选择性输出。本文对近年来报道的有机增益材料和光学谐振腔的种类及特性进行了归纳,总结了具有不同谐振腔结构的有机微腔激光的研究进展,为进一步拓展有机微腔激光器提供借鉴和启发。

关键词：有机激光增益介质晶体谐振腔微腔结构

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强弱耦合板-腔系统的声辐射模态计算与分析

声学学报 2022年第6期47卷 739-747页

作者：廖金龙朱海潮侯九霄袁苏伟海军工程大学振动与噪声研究所船舶振动噪声重点实验室武汉430033

针对板-腔耦合系统的声辐射模态(ARM)计算问题,提出了一种基于能量原理的声辐射模态计算方法,该方法从能量原理的动力学方程构建起声压模态幅值和结构模态幅值的关系,通过将声势能表示为结构模态幅值向量的二次型形式,得到板-腔耦合系... 详细信息

针对板-腔耦合系统的声辐射模态(ARM)计算问题,提出了一种基于能量原理的声辐射模态计算方法,该方法从能量原理的动力学方程构建起声压模态幅值和结构模态幅值的关系,通过将声势能表示为结构模态幅值向量的二次型形式,得到板-腔耦合系统的声辐射模态,弥补了前人理论在解决声腔为阻抗壁面和结构-声为强耦合条件时的不足。通过数值算例验证了本文计算方法的正确性和有效性,在此基础上分析了壁面和结构-声耦合条件变化对声辐射模态特性的影响。结果表明:声辐射模态辐射效率曲线会在声腔模态频率处产生峰值,阻抗壁面的引入会降低声辐射模态辐射效率在峰值处的幅值,并且阻抗值越小,幅值衰减效应越明显,具体表现为声势能曲线在辐射效率峰值频率处幅值会下降;强耦合条件下低频段声势能响应主要由弹性板结构模态激发,响应峰值密度更高,幅值更低。低频同频宽的声辐射模态辐射效率峰值数更少,峰值频率更高。

关键词：辐射效率声辐射模态峰值频率能量原理势能曲线耦合条件阻抗值耦合板