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平原河网地区稻麦轮作农田排水与氮素流失特征研究

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农业机械学报 2024年第3期55卷 321-330页

作者：邹家荣贾忠华朱卫彬刘文龙丁世洪罗纨扬州大学水利科学与工程学院扬州225009 扬州市江都区沿运灌区管理处扬州225261

长江下游稻麦轮作区农田排水是区域面源污染的主要来源,明确农田排水与氮素流失特征对于区域农业生产可持续发展与生态环境保护具有重要意义。现有稻麦轮作农田排水与氮素流失研究中,一般采用农田测筒观测地表径流与深层渗漏量来估算农... 详细信息

长江下游稻麦轮作区农田排水是区域面源污染的主要来源,明确农田排水与氮素流失特征对于区域农业生产可持续发展与生态环境保护具有重要意义。现有稻麦轮作农田排水与氮素流失研究中,一般采用农田测筒观测地表径流与深层渗漏量来估算农田氮素流失量,这与农田土壤水分与氮素主要通过侧向径流进入农田排水系统的实际情况存在偏差。本文基于4年的大田监测数据,运用田间水文水质模型DRAINMOD-NⅡ,模拟研究了不同气象条件下稻麦轮作农田排水与氮素流失规律。结果表明,稻麦轮作周年内,由排水造成的氮素流失量多年平均值为28.4 kg/hm^(2),占施肥量的6.0%,其中大部分集中在稻季,平均为25.6 kg/hm^(2),麦季氮素流失量仅为2.8 kg/hm^(2)。与现有文献报道值相比,本文模拟得出的排水总量高35.4%,氮素流失总量则低44.6%;差异主要来自麦作期,文献报道平均值(31.8 kg/hm^(2))是本文的11倍,估算方法不同可能是造成这一差异大的主要原因。结合降雨规律分析发现,农田排水量和氮素流失量与降雨变化关系显著(决定系数R^(2)>0.56),三者相对增量的变化规律几乎一致;在降雨频率为20%~80%的年份内,氮素流失量相对稳定,维持在均值的0.8~1.2倍之间;只有在重现期大于5年的干旱或湿润年份,氮素流失量才会出现较大变化。因此,通过排灌控制措施稳定农田水文过程是有效控制农田排水氮素流失的关键。

关键词：稻麦轮作农田排水氮素流失 DRAINMOD-NⅡ模型降雨

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HOSM controller design with asymmetric output constraints

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Science China(Information Sciences) 2022年第8期65卷 287-288页

作者： Keqi MEI shihong ding School of Electrical and Information Engineering Jiangsu University

Dear editor,In many control systems, the output constraints are imposed for security reasons and intrinsic physical limitations [1]. For instance, the vibrations of moving strings should be kept within the constrained region to avoid serious hazards [2].Handling output constraints for a controller design is undoubtedly an intractable problem.

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基于固定时间终端滑模的永磁同步电机控制

扬州大学学报（自然科学版） 2024年第2期27卷 15-20页

作者：王震刘洋洪毅洪伟曹金山刘陆丁世宏江苏大学电气信息工程学院江苏镇江212013 德玛克(长兴)注塑系统有限公司浙江湖州313100

为了提高永磁同步电机的鲁棒性和跟踪精度,提出一种新型固定时间终端滑模控制方法.首先,在d-q坐标系中构建永磁同步电机的数学模型,给出q轴电流和电机转速的表达式;其次,通过给出的固定时间终端滑模的滑模面和导出的系统控制输入表达式... 详细信息

为了提高永磁同步电机的鲁棒性和跟踪精度,提出一种新型固定时间终端滑模控制方法.首先,在d-q坐标系中构建永磁同步电机的数学模型,给出q轴电流和电机转速的表达式;其次,通过给出的固定时间终端滑模的滑模面和导出的系统控制输入表达式,实现电机转速的固定时间收敛.仿真结果表明,相比于传统比例积分和滑模算法,所提控制方案可有效改善永磁同步电机的响应速度、运行稳定性和抗干扰性能.

关键词：永磁同步电机终端滑模固定时间

ADAPTIVE SET STABILIZATION OF THE ATTITUDE OF A RIGID SPACECRAFT WITHOUT ANGULAR VELOCITY MEASUREMENTS

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Journal of Systems Science & Complexity 2011年第1期24卷 105-119页

作者： shihong ding Shihua LI Qi LI School of Automation Southeast University Nanjing 210096 China College of Electrical and Information Engineering Jiangsu University Zhenjiang 212013 China School of Automation Southeast University Nanjing 210096 China

The global adaptive set stabilization problem of the attitude of a rigid spacecraft is addressed in this paper. Two different cases are considered. First, by using adaptive backstepping method, the authors design a global adaptive control law for the attitude control system with unknown inertia matrix such that the attitude and the angular velocities can be globally asymptotically stabilized to a set consisting of two equilibria. And then, based on the obtained backstepping adaptive law, the authors consider the case that the angular velocities are not measurable. By introducing an auxiliary state, a semi-global adaptive set stabilization law without angular velocity measurements is also designed. It is rigorously proved that, for the two cases, both of the closed loop systems satisfy the set stability. The effectiveness of the proposed methods is verified by simulation results.

关键词： Adaptive control attitude stabilization backstepping quaternion spacecraft.

Second-Order Sliding Mode Controller Design with a Larger Domain of Attraction

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Journal of Systems Science & Complexity 2020年第1期33卷 61-73页

作者： MEI Keqi ding shihong YANG Xiaofei MA Li School of Electrical and Information Engineering Jiangsu UniversityZhenjiang 212013China School of Electronics and Information Jiangsu University of Science and TechnologyZhenjiang 212003China

In this paper,by combining a second-order sliding mode(SOSM)algorithm with the saturation technique,a novel SOSM control scheme has been *** feature of the proposed SOSM controller lies that there is a saturation function imposed on the sliding variable,which could significantly enlarge the domain of attraction for the closed-loop *** geometric method has been utilized to prove that all the sliding variables will be steered to the origin in a finite ***,the relation between the control parameters and the shape of the phase trajectory has also been ***,the proposed method has been applied to the tracking control problem for a robotic manipulator.

关键词： Finite-time convergence second-order sliding mode stabilization

Stability analysis for a second-order continuous finite-time control system subject to a disturbance

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控制理论与应用（英文版） 2009年第3期7卷 271-276页

作者： shihong ding Shihua LI Qi LI School of Automation Southeast University Nanjing Jiangsu 210096 China

In this paper, using finite-time control method, we consider the disturbance analysis of a second-order system with unknown but bounded disturbance. We show that the states of the second-order system will be stabilized to a region containing the origin. The radius of this region is determined by the control parameters and can be rendered as small as desired. The rigorous stability analysis is also given. Compared with the conventional PD control law, the finite-time control law yields a better disturbance rejection performance. Numerical simulation results show the effectiveness of the method.

关键词： Finite-time control Second-order system Disturbance analysis Bounded disturbance

The Controller Design of the Water-Aerial Vehicle Based on Variable Gain PID

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The Controller Design of the Water-Aerial Vehicle Based on V...

Composite Sliding Mode Control for PMSM Speed Regulation System

第32届中国控制与决策会议

作者： Liu huanxiao Meng Zihan Yang Xiaofei ding shihong School of Information Engineering Zhenjiang Vocational Technical College School of Electronics and Information Jiangsu University of Science and Technology School of Electrical and Information Engineering Jiangsu University

ISBN: (数字)9781728158556

ISBN: (纸本)9781728158563

Combining the advantages of unmanned aerial vehicle（UAV） and unmanned surface vehicle（USV）,water-aerial vehicles satisfy the requirements of operation in water-air amphibious *** to the medium characteristics of air and water are different,it is difficult to maintain stability of the amphibious vehicle in the operation stage of *** order to solve this problem,the mathematical models of the amphibious vehicle are established in different motion stages,and one stability controller is designed based on the variable gain *** simulation results show that the proposed control method is feasible and meets the requirements of the water-air amphibious vehicle.

关键词： Aerial-water Vehicle Control Law Variable Gain PID

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Composite Sliding Mode Control for PMSM Speed Regulation Sys...

第32届中国控制与决策会议

作者： Zhang Lei Xu Bo Ji Wei He Runxin ding Yi ding shihong School of Electrical and Information Engineering Jiangsu University Baidu USA LLC

ISBN: (数字)9781728158556

ISBN: (纸本)9781728158563

In this paper,for the purpose of optimizing the dynamic performance of the permanent magnet synchronous motor（PMSM） speed regulation system,the improved NFTSMC based on a new sliding mode reaching law（NSMRL） is *** NSMRL can dynamically adapt to the variations of the controlled system,which allows chattering reduction on control output while maintaining high tracking performance of the *** further improve the performance of the PMSM system,a composite sliding mode controller is *** control method introduces the internal mode disturbance observer（IMDO） to estimate the load disturbance and adds a feed-forward compensation item to the output of the improved *** results demonstrate that the proposed method has better suppression of chattering effect and disturbance rej ection ability.

关键词： Permanent Magnet Synchronous Motor(PMSM) Sliding Mode Control(SMC) Internal Mode Disturbance Observer(IMDO)

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混合单绕组磁悬浮开关磁阻电机悬浮特性分析

中国电机工程学报 2023年第2期43卷 789-797页

作者：袁野孙玉坤丁世宏杨帆江苏大学电气信息工程学院江苏省镇江市212013

单绕组磁悬浮开关磁阻电机可以实现全功率转矩和转矩/悬浮两种模式运行,具有转矩系统与悬浮系统高度集成的独特优势,但存在悬浮力输出范围有限的弊端。针对上述问题,该文将单绕组磁悬浮开关磁阻电机模块设计,与直流磁悬浮轴承一体化集成... 详细信息

单绕组磁悬浮开关磁阻电机可以实现全功率转矩和转矩/悬浮两种模式运行,具有转矩系统与悬浮系统高度集成的独特优势,但存在悬浮力输出范围有限的弊端。针对上述问题,该文将单绕组磁悬浮开关磁阻电机模块设计,与直流磁悬浮轴承一体化集成,形成混合单绕组磁悬浮开关磁阻电机(hybrid single winding bearingless switched reluctance motor,HSWBSRM)。进一步将HSWBSRM宽支承系统的定子凸极与转子凸极设计为宽齿-窄齿互相配合形式,引入轴向充磁永磁体提供产生悬浮力的偏置磁场,提高悬浮力输出能力,降低了系统的体积与悬浮功耗。该文首先阐明混合单绕组磁悬浮电机结构与运行原理,并揭示设计约束条件。针对典型实验样机参数,构建三维有限元分析模型,着重围绕宽支承系统偏置、主动悬浮特性以及单绕组系统转矩/悬浮特性开展深入分析。最后,在探明宽支承系统与单绕组系统耦合特性的基础上,提出相应控制策略并构建控制系统,验证HSWBSRM悬浮机理的可行性与有效性。

关键词：磁悬浮开关磁阻电机飞轮电池单绕组有限元分析控制策略