滑模变结构理论在船舶减摇鳍中的应用

以船舶减摇鳍控制系统为研究对象,将滑模变结构理论应用于船舶减摇鳍控制系统,提出一种减摇鳍滑模变结构控制器并完成该控制器的理论实现;基于船舶横摇运动的线性方程,对不同浪向下的船舶横摇运动进行系统仿真。结果表明:与常规PID控制相比,滑模变结构控制器具有更好的控制效果和更强的鲁棒性。     

滑模变结构技术在无刷直流电机中的应用

针对永磁无刷直流电机(BLDCM)中采用的输入输出线性化控制方法，对电机参数变化及外加干扰时鲁棒差问题，研究了一种简单的BLDCM滑模变结构控制方法。借助于微分几何理论，将一个具有理想动态性能的线性参考模型引入BLDCM滑模变结构控制器设计之中，设计了基于模型参考滑模变结构的BLDCM控制器。该方法可以使BLDCM具有理想动态特性，在实现对电机状态的精确跟踪的同时，也对电机参数变化和外部干扰具有较强的鲁棒性，最后实验验证理论的正确性。     

潜艇浮筏隔振系统的半主动变结构控制

对带有电流变液智能阻尼器的双层浮筏隔振系统设计了一种半主动输出反馈变结构控制器。根据滑模运动方程稳定的 Hurwitz 判据选择滑模面矩阵。半主动控制条件限制电流变阻尼器可控阻尼力对隔振系统做负功,耗散振动能量。仿真分析了浮筏隔振系统在扫频激励信号下的力传递率及在双频激励信号下的输入力与输出力曲线。同时还仿真分析了双频激励信号作用下半主动静态输出反馈变结构控制下的双层浮筏隔振系统在系统参数出现摄动时的鲁棒性。仿真结果表明：半主动输出反馈变结构控制下的浮筏隔振系统的减振效果要远好于最优被动阻尼系统,对系统参数摄动也具有很强的鲁棒性。     

船舶柴油机燃油温度滑模控制系统设计

运用滑模变结构控制理论,设计一种针对仿射非线性系统的滑模控制器,实现了双输入双输出非线性耦合温度系统的控制.通过在组态王(KINGVIEW)环境下编制控制软件,实现了对柴油机高、低温燃油的温度控制.实验结果显示滑模变结构控制算法对非线性系统的良好的控制效果,解决了传统PID控制超调量大、调节时间及上升时间长的问题.     

双容温度滑模控制系统设计

本文探讨了滑动模态变结构控制(滑模控制设计原则,设计了一种滑模控制器,实现了双输入双输出非线性耦合温度系统的控制,并用组态王(KINGVIEW)编制该控制软件,解决了传统PID控制超调量大、调节时间及上升时间长的问题,体现出滑模变结构控制自适应能力强,动态、静态品质优良,鲁棒性好的特点。     

柴油机调速系统自适应滑模控制算法的研究与仿真

建立2135型柴油机调速器的非线性模型,设计一种滑模控制器,以实现对单输入非线性柴油机调速系统的控制,并用MatLab/Simulink仿真,体现出滑模变结构控制对非线性系统进行控制的动态、静态品质优良,鲁棒性好的特点,解决传统PID控制超调量大、调节时间长的问题.针对滑模变结构控制器容易产生抖振的问题,设计了自适应离散滑模控制器,取得较好的仿真结果.     

基于滑模变结构的船用永磁同步电机直接转矩控制

电力推进在船舶动力系统中应用得越来越多,本文对船用永磁同步电机直接转矩控制进行仿真研究。针对传统永磁同步电机直接转矩控制中存在的磁链和转矩脉动较大,逆变器开关频率不稳定等问题,将滑模变结构控制策略引入。设计转矩和磁链2个滑模控制器,取代传统直接转矩控制中的2个滞环比较器,再运用空间矢量脉宽调制方法,控制电机运行。仿真结果表明这种控制策略能有效减小传统直接转矩控制存在的磁链和转矩脉动,实现逆变器开关频率恒定,并且对系统参数变化及外界扰动具有鲁棒性强的优点。     

基于滑模变结构的船用永磁同步电机直接转矩控制

电力推进在船舶动力系统中应用得越来越多,本文对船用永磁同步电机直接转矩控制进行仿真研究.针对传统永磁同步电机直接转矩控制中存在的磁链和转矩脉动较大,逆变器开关频率不稳定等问题,将滑模变结构控制策略引入.设计转矩和磁链2个滑模控制器,取代传统直接转矩控制中的2个滞环比较器,再运用空间矢量脉宽调制方法,控制电机运行.仿真结果表明这种控制策略能有效减小传统直接转矩控制存在的磁链和转矩脉动,实现逆变器开关频率恒定,并且对系统参数变化及外界扰动具有鲁棒性强的优点.     

船用微型锅炉非线性温度系统控制器仿真与研究

为了实现对船用微型锅炉高、低水温的控制，在Matlab环境下对实测和计算的数据进行曲线拟合，建立了船用微型锅炉水温系统的非线性数学模型。运用滑模变结构控制理论，选取线性切换面和比例型趋近率，设计了一种滑模控制器，实现了双输入双输出非线性耦合温度系统的解耦和控制。通过Matlab／Simulink软件的仿真，结果显示滑模变结构控制算法对非线性系统的控制有响应快、超调小、调节时间短、无误差和抖动的特点。     

高精度随动系统的变结构控制

陀螺稳定平台控制系统是控制平台框架系统快速跟踪陀螺仪的高精度随动系统,是保证平台正常工作和精度的重要系统。用传统的PID调节器可以满足工作在系统线性区的要求。由于放大器、电机等存在饱和特性,因而在系统启动和随大的干扰产生大偏角时,系统将进入非线性区,PID调节器将难以满足稳定性的要求。滑模变结构控制器对非线性具有很好的适应性,对系统启动初始偏角没有限制要求,本文将应用变结构控制的方法对平台的控制系统进行设计。     

半潜型浮式风机运动特征及系泊系统的研究

近年来海上浮式风机的研究备受关注,安全可靠的系泊系统将保证风机在风、浪、流等复杂环境荷载作用下稳定运行,准确合理地描述风机运动将为评估风机发电效率提供支持。以半潜型浮式风机的系泊系统为研究对象,基于经典悬链线理论,采用准静态分析法提出一套系泊系统的设计方法。通过坐标变换,得到风轮真实的俯仰运动用于计算风机的动力效应及评定其发电效率。采用动力法分析了系泊系统锚链的导缆孔位置、预张力大小、锚链间夹角等参数对风机系统发电效率、浮式平台运动性能和系泊锚链张力的影响,得到了浮式平台迎风面俯仰倾角、水平偏移及锚链张力随参数的变化规律,为半潜型浮式风机系泊系统的设计提供了参考。     

Model test investigation of a spar floating wind turbine

Several floating wind turbine designs whose hull designs reflect those used in offshore petroleum industry have emerged as leading candidates for the future development of offshore wind farms. This article presents the research findings from a model basin test program that investigated the dynamic response of a 1:50 scale model OC3 spar floating wind turbine concept designed for a water depth of 200 m. In this study the rotor was allowed to rotate freely with the wind speed and this approach eliminated some of the undesirable effects of controlling wind turbine rotational speed that were observed in earlier studies. The quality of the wind field developed by an array of fans was investigated as to its uniformity and turbulence intensity. Additional calibration tests were performed to characterize various components that included establishing the baseline wind turbine tower frequencies, stiffness of the delta type mooring system and free decay response behaviour. The assembled system was then studied under a sequence of wind and irregular wave scenarios to reveal the nature of the coupled response behaviour. The wind loads were found to have an obvious influence on the surge, heave and pitch behaviour of the spar wind turbine system. It was observed from the experimental measurements that bending moment at the top of the support tower is dominated by the 1P oscillation component and somewhat influenced by the incoming wave. Further it was determined that the axial rotor thrust and tower-top shear force have similar dynamic characteristics both dominated by tower’s first mode of vibration under wind-only condition while dominated by the incident wave field when experiencing wind-wave loading. The tensions measured in the mooring lines resulting from either wave or wind-wave excitations were influenced by the surge/pitch and heave couplings and the wind loads were found to have a clear influence on the dynamic responses of the mooring system.     

Integrated design optimization of spar floating wind turbines

A linearized aero-hydro-servo-elastic floating wind turbine model is presented and used to perform integrated design optimization of the platform, tower, mooring system, and blade-pitch controller for a 10 MW spar floating wind turbine. Optimal design solutions are found using gradient-based optimization with analytic derivatives, considering both fatigue and extreme response constraints, where the objective function is a weighted combination of system cost and power quality. Optimization results show that local minima exist both in the soft-stiff and stiff-stiff range for the first tower bending mode and that a stiff-stiff tower design is needed to reach a solution that satisfies the fatigue constraints. The optimized platform has a relatively small diameter in the wave zone to limit the wave loads on the structure and an hourglass shape far below the waterline. The shape increases the restoring moment and natural frequency in pitch, which leads to improved behaviour in the low-frequency range. The importance of integrated optimization is shown in the solutions for the tower and blade-pitch control system, which are clearly affected by the simultaneous design of the platform. State-of-the-art nonlinear time-domain analyses show that the linearized model is conservative in general, but reasonably accurate in capturing trends, suggesting that the presented methodology is suitable for preliminary integrated design calculations.     

船舶可调桨螺距模糊PID控制器设计

针对柴油机驱动的船舶可调桨推进系统,从运动学和动力学角度建立与其适应的船桨系统、柴油机系统、调速控制系统和螺距控制系统的运动模型.同时运用模糊控制和PID控制理论,在Matlab仿真平台上设计可调桨螺距的模糊PID控制器,调试运行使之与可调桨动力性能相匹配,得到相应螺距偏差、偏差变化率和螺距控制输出量隶属度数据.通过仿真过程离线计算得到模糊控制器输出控制量查询表,从而设计完成可调桨螺距的模糊PID控制器.针对可调桨螺距控制,给定车钟指令信号和脉冲干扰信号.仿真实验结果证明,模糊PID控制器能有效避免可调桨控制跳动问题,且其控制速度、精度和灵敏度较传统PID控制器具有显著优势.     

船用蒸汽发生器给水控制系统仿真试验平台的设计与实现

针对船用汽轮给水泵转速控制系统中自能源进汽调节阀改为电动进汽调节阀的改进方案,设计并实现了一种船用蒸汽发生器给水控制系统仿真试验平台,建立了船用蒸汽发生器给水控制系统数学模型,包括蒸汽发生器数学模型、汽轮给水泵数学模型、给水管道及给水调节阀数学模型,设计了蒸汽发生器水位控制器以及汽轮给水泵转速控制器,通过与模拟机仿真结果比较验证了仿真试验平台的有效性.     

气垫船垫升推进系统控制仿真

以某型气垫船的动力系统为对象,建立了垫升推进系统的数学模型及船体的运动学模型,并以SIMULINK为平台对该系统进行了仿真建模[1],在此基础上,通过对系统动态特性的分析,对该系统进行了简单PID控制器和串级PID控制器的设计,并分别对两类控制系统进行了动态仿真和比较分析.仿真结果表明,串级PID控制系统较简单PID控制系统具有更为优越的动态性能,能较好地保证气垫船的垫态稳定性,以满足工程要求.     

单柱式浮式风力机动力响应数值与试验分析

以200 m作业水深的5 MW OC3单柱式浮式风力机为研究对象,采用FAST程序对其在不同海况下的运动进行全耦合时历数值计算,并与采用1∶50缩尺比模型试验所得时历结果进行对比,通过时域以及频域方法对平台主要自由度运动以及系泊拉力进行分析。研究发现:垂向运动带来的自由面记忆效应较纵向和横向小;悬链线式模型所能提供的系泊拉力较张紧式系泊提供的拉力小;风浪联合作用下,风载荷主要激励低频固有频率运动,波浪载荷则主要激励波频运动;平台纵荡和纵摇运动受系泊系统的影响较大,而垂荡运动则不受系泊系统的影响。     

浅吃水单柱式浮式风机动力学特性仿真研究

本文采用FAST软件对一种浅吃水单柱式浮式风机系统的动力学特性进行了研究.这一浮式风机适用于能源成本相对合理、水深为150 m的海域.本文首先讨论了这一浮式风机系统和OC3-Hywind系统在动力学特性方面的差异,然后研究了风尤其是湍流风对系统动力学特性的影响,最后对这一系统在多种载荷状况下的动力学行为进行了详尽的分析.研究结果表明:湍流风会在系统固有频率附近引起显著的激励;纵荡和纵摇运动取决于风轮推力,它们通过风轮推力和相对风速之间的联系建立起耦合关系;Spar平台的艏摇运动主要取决于平台横摇时由风轮推力引起的艏摇力矩.     

基于模糊PID控制器的海上风电机系统仿真模拟

当海上风电机的风轮运转时,由于风速的变化和风力涡轮机的惯性,风轮速度的变化不能与风速的变化保持同步,因此控制系统长时间处于瞬态过程中。文章主要研究了海上风力发电机仿真模拟技术和模糊PID控制器设计。通过Matlab建立了风机Simulink模型。与传统的PID控制相比,模糊PID控制器具有快速响应和良好的动态特性。     

Semi-submersible wind turbine hull shape design for a favorable system response behavior

Floating offshore wind turbines are a novel technology, which has reached, with the first wind farm in operation, an advanced state of development. The question of how floating wind systems can be optimized to operate smoothly in harsh wind and wave conditions is the subject of the present work. An integrated optimization was conducted, where the hull shape of a semi-submersible, as well as the wind turbine controller were varied with the goal of finding a cost-efficient design, which does not respond to wind and wave excitations, resulting in small structural fatigue and extreme loads.The optimum design was found to have a remarkably low tower-base fatigue load response and small rotor fore-aft amplitudes. Further investigations showed that the reason for the good dynamic behavior is a particularly favorable response to first-order wave loads: The floating wind turbine rotates in pitch-direction about a point close to the rotor hub and the rotor fore-aft motion is almost unaffected by the wave excitation. As a result, the power production and the blade loads are not influenced by the waves. A comparable effect was so far known for Tension Leg Platforms but not for semi-submersible wind turbines. The methodology builds on a low-order simulation model, coupled to a parametric panel code model, a detailed viscous drag model and an individually tuned blade pitch controller. The results are confirmed by the higher-fidelity model FAST. A new indicator to express the optimal behavior through a single design criterion has been developed.