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Disturbance Observer-based Trajectory Tracking Control of Unmanned Surface Vehicles with Unknown Disturbances and Input Saturation 36

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Disturbance Observer-based Trajectory Tracking Control of Un...

第36届中国控制会议

作者： Ying Gao Ning Wang zhongjiu zheng Marine Engineering College Dalian Maritime University

ISBN: (纸本)9781538629185

This paper addresses the problem of trajectory tracking control for an unmanned surface vehicle（USV） with unknown disturbances and input *** the saturation function is divided into a smooth function and a bounded function,the saturation function can be approximated by smooth function and the bounded function which can be treated as a system *** auxiliary design system is employed to address input constraint *** bounded function and unknown disturbances are lumped together and an observer is constructed to observe the total disturbances that reduce the influence and undesirable inaccuracy due to time-vary *** on the information of the disturbances observer and backstepping control technique,the trajectory tracking controller of an unmanned surface vehicle is ***,it is proved that the stability of closed-loop system and the convergence of tracking errors by Lyapunov *** studies demonstrate the effectiveness of the proposed approach.

关键词： Trajectory Tracking Disturbance Observer Input Saturation Unmanned Surface Vehicle

An Improved Siding Mode Controller in PMSM Control System for Smoother Speed Response and Stronger Robustness

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An Improved Siding Mode Controller in PMSM Control System fo...

第30届中国控制与决策会议

作者： Hong Zhao Peng Luo Ning Wang zhongjiu zheng Derun Zhao Marine Electrical Engineering College Dalian Maritime University

The PI controller in the Permanent Magnet Synchronous Motor（PMSM） control system has the disadvantages of weak robustness and poor anti-interference ability, therefore the Sliding Mode Control（SMC） is proposed to improve the control effect and enhance the robustness of the system. However, the switching control part in the design of the traditional sliding mode controller is usually switched by the sign function, which can make the chattering phenomenon arise in the system. In order to reduce the chattering and further improve the control performance of the PMSM, a saturation function was proposed in this paper to replace the sign function to reduce the chattering phenomenon on the sliding surface. The simulation results obtained in the Matlab/Simulink show that the improved sliding mode controller can improve both the dynamic performance and anti-interference ability of the PMSM control system.

关键词： PMSM SMC Sign function Saturation function

Fuzzy Logic Control of the Fault-tolerant PMSM Servo System Based on MRAS Observer

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Fuzzy Logic Control of the Fault-tolerant PMSM Servo System ...

第30届中国控制与决策会议

作者： Hong Zhao Peng Luo Ning Wang zhongjiu zheng Yiting Wang Marine Electrical Engineering College Dalian Maritime University

In order to make the Permanent Magnet Synchronous Motor(PMSM) propulsion system operate normally when its position sensor failure occurs, the Model Reference Adaptive System(MRAS) observer estimation algorithm is put forward to estimate the rotor speed and the rotor angle thus enhancing the fault-tolerant capability of the whole propulsion system. However, under the PMSM servo control system which is based on SVPWM control strategy, the traditional PI controller has the disadvantages of weak robustness and poor anti-interference ability. Therefore, the Fuzzy Logic Control(FLC) is proposed to improve the control effect and enhance the robustness of the system. Finally, a simulation model based on the complete system combining the FLC and the MRAS observer is established in the Matlab/Simulink environment to testify the proposed strategy. Simulation results show that the proposed strategy can not only improve the dynamic performance and anti-interference ability of the PMSM control system greatly, but also estimate the rotor speed and angle effectively when the position sensor fails, thus the fault-tolerant capability of the whole propulsion system can be enhanced.

关键词： PMSM MRAS Observer Fault-tolerant capability FLC SVPWM

Brushless DC Motor Control via Fuzzy Systems with Variable Contraction-expansion factors

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Brushless DC Motor Control via Fuzzy Systems with Variable C...

第30届中国控制与决策会议

作者： Hong Zhao Peng Luo Ning Wang zhongjiu zheng Derun Zhao Marine Electrical Engineering College Dalian Maritime University

The Brushless DC Motor（BLDCM） is non-linear, multi-variable, tightly coupled. It has been widely researched in the field of motor control. However, the traditional PI controller method is vulnerable to uncertain factors in the BLDCM drive system, for instance, load disturbance and the motor parameters change, which have an impact on obtaining satisfactory control effects. This paper proposes an adaptive variable universe fuzzy PI compound control strategy with contraction-expansion factors. The self-adjustment of PI control parameters and control rules can be acquired by using variable universe adaptive fuzzy control. Finally, a double closed-loop control system of the BLDCM based on the adaptive variable universe fuzzy control algorithm is designed in Matlab/Simulink environment. Simulation results show that the BLDCM drive system based on the proposed method has faster dynamic response, stronger robustness and anti-interference ability.

关键词： Brushless DC Motor Fuzzy PI Variable Universe Contraction-expansion Factor

Nonlinear Disturbance Observer-based Sliding Backstepping Hovering Control of a Quadrotor

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Nonlinear Disturbance Observer-based Sliding Backstepping Ho...

第30届中国控制与决策会议

作者： Ning Wang Qi Deng Hong Zhao Jianchuan Yin zhongjiu zheng Center for Intelligent Marine Vehicles Dalian Maritime University

In this paper, the nonlinear observer based hovering control is addressed for a quadrotor with system uncertainties and external disturbances. Main contributions are as follows: 1) A nonlinear observer for complex unknowns including unmodelled dynamics and external disturbances is designed for a quadrotor, and thereby contributing to more robustness pertaining to the closed-loop system;2) The sliding backstepping based technique is then employed to realize hovering control of a quadrotor, and thereby leading to the proposed controller which achieves satisfactory control performance;3) Exhaustive analyses ensure that tracking errors of the overall system can converge to a small neighborhood of the origin. Furthermore, a large number of simulation experiments show the effectiveness of the proposed control law.

关键词： Sliding Mode Control Backstepping Control Nonlinear Disturbance Observer Quadrotor Hovering Control

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升温过程中弱黏煤磁性变化关键因素实验研究

煤矿安全 2022年第6期53卷 50-56页

作者：韩文彬吴晗秦政任仲久国能神东煤炭集团保德煤矿山西保德036600 吕梁市能源局山西吕梁033000 中煤科工集团沈阳研究院有限公司辽宁抚顺113122 煤矿安全技术国家重点实验室辽宁抚顺113122

为了研究黄陇煤田弱黏煤在升温过程中磁性变化机制,测定升温过程中煤样的质量磁化率,与同等温度热处理后的烧变煤样对比,将煤在升温中的磁变过程划分为4个阶段,分别针对不同阶段开展弱黏煤的程序升温、工业分析及X射线衍射等实验,探究... 详细信息

为了研究黄陇煤田弱黏煤在升温过程中磁性变化机制,测定升温过程中煤样的质量磁化率,与同等温度热处理后的烧变煤样对比,将煤在升温中的磁变过程划分为4个阶段,分别针对不同阶段开展弱黏煤的程序升温、工业分析及X射线衍射等实验,探究不同升温阶段导致其磁性变化的关键性因素。结果表明:在常温至200℃范围内,煤样质量磁化率由负转正缓慢升高,此阶段影响煤体磁性的主要原因是煤体中显逆磁性的含碳化合物组分由于氧化消耗而下降;在200~350℃区间,煤样中微量矿物发生化学反应生成顺磁性更强的物质,致使煤样磁化率急剧上升,平均增长率超过上一阶段10倍;350℃后磁化率开始迅速降低,500℃后平稳于0点附近,主要矿物内部微粒运动由于随温度的升高而加剧,影响磁畴磁矩的有序排列,升至居里温度时,这种影响达到极限,变化趋于稳定。

关键词：煤矿安全煤田火灾磁法探测煤岩磁性质量磁化率

丙硫咪唑和噻嘧啶混合疗法驱除肠道线虫的效果观察

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实用寄生虫病杂志 1996年第3期4卷 103-107页

作者：张德洪陈闯张孝蓉唐中玖杨文锦陈亚伟张大发刘显陶石可华伍树明郑荣富黎秀齐陈世伦封厚培四川省寄生虫病防治研究所四川省垫江县卫生防疫站四川省涪陵地区卫生防疫站

本文报道丙硫咪唑４００ｍｇ、２００９与噻嘧啶７５０ｍｇ（基质２５０ｍｇ）的两种混合疗法，一次量顿服的钩虫、蛔虫和鞭虫的虫卵阴转率分别为７２．８％和６８．８％、１００％和９９．２％及２８．９％和３０．０％，两者对３种线... 详细信息

本文报道丙硫咪唑４００ｍｇ、２００９与噻嘧啶７５０ｍｇ（基质２５０ｍｇ）的两种混合疗法，一次量顿服的钩虫、蛔虫和鞭虫的虫卵阴转率分别为７２．８％和６８．８％、１００％和９９．２％及２８．９％和３０．０％，两者对３种线虫的疗效差异均不显著（Ｐ均＞０．０５）；驱除钩虫效果均显著优于丙硫咪唑和噻嘧啶对照组（Ｐ均＜０．０１）．显示混合疗法具有协同作用；驱除蛔虫和鞭虫的效果均与两个对照组相近（Ｐ均＞０．０５）。淘虫结果证明其驱虫作用均明显较丙硫咪唑为快。副作用轻微短暂，无蛔虫游走所致的副反应。

关键词：丙硫咪唑噻嘧啶混合疗法钩虫蛔虫鞭虫

深部破碎软岩巷道超前控顶加固及控制爆破技术

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爆破 2024年第3期41卷 75-84页

作者：汪禹张西良李龙福殷登才崔正荣王小兵金科金属矿山安全与健康国家重点实验室马鞍山243000 马鞍山矿山研究院爆破工程有限责任公司马鞍山243000 中钢集团马鞍山矿山研究总院股份有限公司马鞍山243000 安徽马钢矿业资源集团姑山矿业有限公司马鞍山243111

随着矿山开采深度逐渐增加,深部破碎围岩工程地质条件转为复杂多变,极大程度上影响巷道等工程施工过程及后续使用安全;为确保深部破碎软岩巷道施工过程中安全及质量,提出了软岩巷道超前控顶加固及控制爆破技术。针对钟九铁矿-550 m水平... 详细信息

随着矿山开采深度逐渐增加,深部破碎围岩工程地质条件转为复杂多变,极大程度上影响巷道等工程施工过程及后续使用安全;为确保深部破碎软岩巷道施工过程中安全及质量,提出了软岩巷道超前控顶加固及控制爆破技术。针对钟九铁矿-550 m水平6号交岔点岩体裂隙极为发育、稳定性差等特点,拟采用超前控顶措施加固顶板围岩,提高深部破碎软岩巷道的承载力。为便于6号交岔点掘进施工,沿6号交岔点东北侧方向划分17个掘进区,并采用“四步”台阶法分段施工。针对同段起爆数码电子雷管,起爆器系统可随机设置单发雷管起爆间隔时间为3~5 ms,实现同段炮孔单孔单响,降低爆破振动对6号交岔点影响。根据不同掘进区总体岩性情况,优化支护方式(管棚支护、W型钢带及锚索支护等联合支护方式等),确保6号交岔点后续使用期安全。试验结果表明:采用超前控顶加固、控制分区爆破技术,降低破碎软岩巷道顶板偏帮、下沉,保证6号交岔点断面成型效果,削减其支护、后期维护等综合成本达8.7%,该技术可为类似巷道施工提供一定指导建议。

关键词：破碎软岩台阶法施工支护方式数码电子雷管

10 MeV、>80 Gy/s@1 m的光子FLASH放疗射线源

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强激光与粒子束 2023年第12期35卷 114-115页

作者：单李军周征羊奕伟刘宇王建新张德敏肖德鑫张鹏闫陇刚李雷曹传宇张小丽桑子儒胥汉勋王诗岚程德琪唐镭迅刘贤洪何心坦杨兴繁王汉斌甘孔银吴岱黎明陈门雪胡进光赵剑衡范国滨中国工程物理研究院应用电子学研究所四川绵阳621900 哈尔滨工程大学核科学与技术学院哈尔滨150001 南华大学核科学技术学院湖南衡阳421001 中玖闪光医疗科技有限公司四川绵阳621000 中国工程物理研究院四川绵阳621900

报道了基于常温射频直线加速器建成的10 MeV光子FLASH放疗射线源样机,采用高平均电流电子束轰击高速旋转辐射转化靶,在距离靶点1 m远处的固体水模内,X射线剂量率达到80.5 Gy/s,达到未来临床实验与推广所需剂量率阈值。

关键词： FLASH放疗超高剂量率医用直线加速器 X射线源

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