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Control Efficacy of Validamycin A·(0.2 Billion Spores/ml) Paenibacillus polymyxa DN-1 3% AS for Rice Sheath Blight
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作者 胡飞 苏卫华 +4 位作者 李昌春 周子燕 胡本进 徐丽娜 郑进国 《Agricultural Science & Technology》 CAS 2016年第11期2615-2618,共4页
With validamycin A.(0.2 billion spores/ml) Paenibacillus polymyxa DN-1 3% AS as the test agent, the effects of different dosage and different application time on the control efficacy for' rich sheath blight were in... With validamycin A.(0.2 billion spores/ml) Paenibacillus polymyxa DN-1 3% AS as the test agent, the effects of different dosage and different application time on the control efficacy for' rich sheath blight were investigated. The results of two- year test showed that when the application amount was in the range of 45-90 g.a.i/ hm^2, the field efficacy of validamycin A-(0.2 billion spores/ml) P. polymyxa DN-1 3% AS in the initial infection stage of rich sheath blight (Le., the diseased plant rate was below 5%) reached 80.38%-89.06%, and that in the peak infection stage (i.e., the diseased plant rate was higher than 10%) reached only 41.12%-53.26%. The field efficacy of validamycin A.(0.2 billion spores/ml) P. polymyxa DN-1 3% AS at the early onset of rich sheath blight was significantly better than that at the onset, so that the application time of validamycin A .(0.2 billion spores/ml) P. polymyxa DN-1 3% AS should be appropriately brought forward in the prevention and control of rice sheath blight. 展开更多
关键词 Validamycin A-(0.2 billion spores/roll P. polymyxa DN-1 3% AS Rice sheath blight Initial infection stage Peak infection stage control efficacy
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Chemical Control of Herbicide Monosulfuron Plus Propazine 44% WP against Weeds in Millet Fields and Study on Factors Influencing Yield of Millet 被引量:2
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作者 周汉章 刘环 +6 位作者 宋银芳 任中秋 薄奎勇 寇俊杰 侯升林 董立 王新玉 《Agricultural Science & Technology》 CAS 2012年第5期1014-1020,共7页
[Objective] The paper was to resolve the poor efficacy or phytotoxicity problems in promotion of herbicide monosulfuron plus propazine 44% WP. [Method] Using orthogonal test and Duncan's new multiple range statistica... [Objective] The paper was to resolve the poor efficacy or phytotoxicity problems in promotion of herbicide monosulfuron plus propazine 44% WP. [Method] Using orthogonal test and Duncan's new multiple range statistical analysis with four factors four levels and three factors two levels, the effects of factors such as herbi- cide dose, irrigation water volume, quality of soil preparation and soil moisture content on chemical control of monosulfuron plus propazine 44% WP against weeds and millet yield were compared in the test. [Result] Seven factors all had great impact on control effect of monosulfuron plus propazine 44% WP against weeds, of which her- bicide dose, irrigation water volume, quality of soil preparation and soil moisture content were the most important factors affecting millet yield. According to millet yield and economic benefit, the optimal scheme to ensure safe, efficient and economic control of monosulfuron plus propazine 44% WP against weeds was as follows: the dose of monosulfuron plus propazine 44% WP was 1 800 g/hm2, the soil was treat- ed after sowing and before seedling emergence; the soil should be smooth and sol- id; the soil moisture should reach 15%; the fields should not be irrigated after herbi- cide application, and the damage of weeds in millet fields could be effectively con- trolled within 45 d during high efficacy duration, especially the damage of dicotyledonous weeds. [Conclusion] The study provided useful information for comprehensive technology of weeds control and ensuring high yield and good harvest of millet. 展开更多
关键词 MILLET HERBICIDE Monosulfuron plus propazine 44% WP WEEDS Chemical control
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Control of Maize Head Smut with 6% Tebuconazole FS
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作者 石凤梅 《Agricultural Science & Technology》 CAS 2014年第5期860-861,865,共3页
In order to test the control effect of 6% tebuconazole FS on maize head smut and to select its optimal dose for mixing seed, field tests were performed in 2012 and 2013. The results showed that 6% tebuconazole FS was ... In order to test the control effect of 6% tebuconazole FS on maize head smut and to select its optimal dose for mixing seed, field tests were performed in 2012 and 2013. The results showed that 6% tebuconazole FS was effective to control maize head smut, and the control effect ranged from 73.4% to 91.1%. In addition, it also improved the maize yield by 36.7%-44.1%, compared with the blank control. The optimal dose of 6% tebuconazole FS for seed dressing was 166.5 g/100 kg to control head smut on maize. 展开更多
关键词 6% Tebuconazole FS Maize head smut control effect
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Efficacy of Difenoconazole-azoxystrobin 32.5% SC in Treatment of Rice Sheath Blight and Its Application Technology 被引量:2
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作者 李海亮 王会福 余山红 《Agricultural Science & Technology》 CAS 2014年第9期1589-1592,共4页
[Objective] The efficacy of difenoconazole-azoxystrobin 32.5% SC for rice sheath blight and its application technology were discussed in this research. [Method] Three surveys were carried out. There were 5 fixed test ... [Objective] The efficacy of difenoconazole-azoxystrobin 32.5% SC for rice sheath blight and its application technology were discussed in this research. [Method] Three surveys were carried out. There were 5 fixed test clumps in each plot. The number of total plants and disease plants and disease progression in each fixed clump were recorded. The correlation effectiveness was calculated based on the growth rate of disease index. Significance analysis was performed with Dun- can's new multiple range method (DMRT). [Result] The difenoconazole-azoxystrobin 32.5% SC had a good efficacy for rice sheath blight, and its efficacy increased with the increase of dose. If sprayed according to the dose of 450 ml/hm2 5 days before the beginning of heading stage of rice, difenoconazole-azoxystrobin 32.5% SC would have better effects on controlling rice sheath blight with correlation effectiveness reaching up to 95.14%, which was 2.06% higher than that of control drug (trifloxys- trobin-tebuconazole 75% WG, 225 g/hm2). [Conclusion] Treated with difenoconazole- azoxystrobin 32.5% SC with dose of 450 ml/hm2, rice would have green upper leaves and less yellow middle and lower leaves. Moreover, the yield was in- creased significantly. The difenoconazole-azoxystrobin 32.5% SC had good safety. Therefore, difenoconazole-azoxystrobin 32.5% SC had a good application prospect in production. 展开更多
关键词 Difenoconazole-azoxystrobin 32.5% SC Rice sheath blight controlling efficiency SAFETY
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H_∞ Consensus Control of Discrete-Time Multi-Agent Systems Under Network Imperfections and External Disturbance 被引量:13
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作者 Arezou Elahi Alireza Alfi Hamidreza Modares 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第3期667-675,共9页
This paper presents a distributed control protocol for consensus control of multi-agent systems(MASs) under external disturbances and network imperfections, including communication delay and random packet dropout. To ... This paper presents a distributed control protocol for consensus control of multi-agent systems(MASs) under external disturbances and network imperfections, including communication delay and random packet dropout. To comply with the discrete nature of networked systems, in contrast to most of the existing work for MASs under network imperfections,the agents are modeled by discrete-time dynamics. The communication network is considered to be undirected, its delay is considered to be time-varying but bounded, and its packet dropout is modeled by a Bernoulli distributed white sequence.Sufficient conditions in terms of linear matrix inequalities(LMIs)for asymptotic mean-square consensus stability are derived under network imperfections without considering external disturbances.A desired disturbance attenuation level in the presence of both external disturbances and network imperfections is also provided.A simulation example is given to verify the effectiveness of the proposed approach in coping with network imperfection and disturbances. 展开更多
关键词 CONSENSUS distributed control H∞ control packet DROPOUT stability time delay
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H_∞ Control of Bio-dissimilation Process of Glycerol to 1,3-Propanediol 被引量:10
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作者 XU Gong-Xian SHAO Cheng XIU Zhi-Long 《自动化学报》 EI CSCD 北大核心 2006年第1期112-119,共8页
A robust controller is designed by using the bilinear transformation and H∞ mixed sensitivity method for bio-dissimilation process of glycerol to 1,3-propanediol. Under the controller the system works near an optimal... A robust controller is designed by using the bilinear transformation and H∞ mixed sensitivity method for bio-dissimilation process of glycerol to 1,3-propanediol. Under the controller the system works near an optimal steady-state for the volumetric productivity of 1,3-propanediol attaining its maximization. The design procedure is carried out by tuning the transformation parameter and DC gain of the performance weighted function, which is an iterative and optimal search process. Simulation results are presented which show that the designed robust controller not only ensures the robust stability of the system in face of the parametric variations in the model, but also makes the system have a favourable robust tracking performance. The validity of the proposed H∞ controller has been tested. 展开更多
关键词 H∞控制 混合灵敏度 双线性转换 生物过程控制 鲁棒控制
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Delay-dependent Robust H∞ Control for Uncertain Singular Systems with State Delay 被引量:22
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作者 FANG Mei 《自动化学报》 EI CSCD 北大核心 2009年第1期65-70,共6页
这份报纸讨论延期依赖者的问题为有州的延期的不明确的单个系统的柔韧的 H 控制。把途径基于线性矩阵不平等(LMI ) ,我们设计一个州的反馈控制器,它保证为所有可被考虑的无常,结果的靠近环的系统是常规的,推动与 H 免费、稳定的标... 这份报纸讨论延期依赖者的问题为有州的延期的不明确的单个系统的柔韧的 H 控制。把途径基于线性矩阵不平等(LMI ) ,我们设计一个州的反馈控制器,它保证为所有可被考虑的无常,结果的靠近环的系统是常规的,推动与 H 免费、稳定的标准界限限制。所有获得的结果是延期依赖者并且由不包含系统矩阵的分解的严格的 LMI 提出。数字例子证明建议方法不比存在的保守。 展开更多
关键词 奇数时间延误系统 延迟依赖 自动控制 线性平均直径
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Improved Results on Delay-dependent H∞ Control for Singular Time-delay Systems 被引量:14
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作者 WU Zheng-Guang SU Hong-Ye CHU Jian 《自动化学报》 EI CSCD 北大核心 2009年第8期1101-1106,共6页
关键词 时滞广义系统 控制方法 泛函系统 计算方法
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Quantized Dynamic Output Feedback H∞ Control for Discrete-time Systems with Quantizer Ranges Consideration 被引量:7
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作者 CHE Wei-Wei YANG Guang-Hong 《自动化学报》 EI CSCD 北大核心 2008年第6期652-658,共7页
使量子化的动态产量反馈 H 控制为的问题分离时间线性时间不变(LTI ) 系统在这份报纸被调查。考虑的 quantizer 动态、镇静一可调节激增参数和静态的 quantizer。静态的 quantizer 范围具有实际意义并且充分被考虑。首先,考虑量子化错... 使量子化的动态产量反馈 H 控制为的问题分离时间线性时间不变(LTI ) 系统在这份报纸被调查。考虑的 quantizer 动态、镇静一可调节激增参数和静态的 quantizer。静态的 quantizer 范围具有实际意义并且充分被考虑。首先,考虑量子化错误,使量子化的控制策略控制器状态依赖于不仅而且在系统测量产量上,它被建议以便使量子化的靠近环的系统是 asymptotically 稳定的,与规定 H,性能跳。根据这结果,然后,一个反复的基于 LMI 的优化算法被开发优化静态的 quantizer 范围为靠近环的系统满足 H 表演要求。一个例子被举说明建议方法的有效性。 展开更多
关键词 离散时间系统 量子学 动力系统 反馈控制系统
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Distributed H_∞ control of multi-agent systems with directed networks 被引量:6
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作者 刘伟 柳爱利 周绍磊 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期73-79,共7页
This paper studies the distributed H∞control problem of identical linear time invariant multi-agent systems subject to external disturbances. A directed graph containing a spanning tree is used to model the communica... This paper studies the distributed H∞control problem of identical linear time invariant multi-agent systems subject to external disturbances. A directed graph containing a spanning tree is used to model the communication topology. Based on the relative states of the neighbor agents and a subset of absolute states of the agents, distributed static H∞controllers are proposed. The concept of an H∞performance region is extended to the directed graph situation. Then the results are used to solve the leader–follower H∞consensus problem. Sufficient conditions are proposed based on bounded real lemma and algebraic graph theory. The effectiveness of the theoretical results is illustrated via numerical simulations. 展开更多
关键词 multi-agent systems H∞ control performance region leader–follower H∞ consensus
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Robust and Non-fragile H_∞ Control for a Class of Uncertain Jump Linear Systems 被引量:6
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作者 KANG Yu XI Hong-Sheng ZHANG Da-Li JI Hai-Bo 《自动化学报》 EI CSCD 北大核心 2006年第3期438-443,共6页
This paper describes the synthesis of robust and non-fragile H∞ state feedback controllers for a class of uncertain jump linear systems with Markovian jumping parameters and state multiplicative noises. Under the ass... This paper describes the synthesis of robust and non-fragile H∞ state feedback controllers for a class of uncertain jump linear systems with Markovian jumping parameters and state multiplicative noises. Under the assumption of a complete access to the norm-bounds of the system uncertainties and controller gain variations, sufficient conditions on the existence of robust stochastic stability and γ-disturbance attenuation H∞ property are presented. A key feature of this scheme is that the gain matrices of controller are only based on It, the observed projection of the current regime rt. 展开更多
关键词 鲁棒控制 Markovian过程 跳跃参数 稳定性
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Robust H-infinity fault-tolerant control for uncertain descriptor systems by dynamical compensators 被引量:7
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作者 BingLIANG GuangrenDUAN 《控制理论与应用(英文版)》 EI 2004年第3期288-292,共5页
The problem of robust H-infinity fault-tolerant control against sensor failures for a class of uncertain descriptor systems via dynamical compensators is considered. Based on H-infinity theory in descriptor systems, a... The problem of robust H-infinity fault-tolerant control against sensor failures for a class of uncertain descriptor systems via dynamical compensators is considered. Based on H-infinity theory in descriptor systems, a sufficient condition for the existence of dynamical compensators with H-infinity fault-tolerant function is derived and expressions for the gain matrices in the compensators are presented. The dynamical compensator guarantees that the resultant colsed-loop system is admissible; furthermore, it maintains certain H-infinity norm performance in the normal condition as well as in the event of sensor failures and parameter uncertainties. A numerical example shows the effect of the proposed method. 展开更多
关键词 Fault-tolerant control H-infinity control Uncertain descriptor systems Sensor failures
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H_∞ Control for 2-D Discrete State Delayed Systems in the Second FM Model 被引量:3
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作者 XU Jian-Ming YU Li 《自动化学报》 EI CSCD 北大核心 2008年第7期809-813,共5页
这份报纸涉及 H 控制的问题为二维(2-D ) 分离州的延期系统由第二 Fornasini 和 Marchesini (FM ) 描述了州空间当模特儿。为这个 2-D 系统有 H 噪音变细的一个足够的条件以某个线性矩阵不平等(LMI ) 被给。最佳的 H 控制器被解决一个... 这份报纸涉及 H 控制的问题为二维(2-D ) 分离州的延期系统由第二 Fornasini 和 Marchesini (FM ) 描述了州空间当模特儿。为这个 2-D 系统有 H 噪音变细的一个足够的条件以某个线性矩阵不平等(LMI ) 被给。最佳的 H 控制器被解决一个凸的优化问题获得。最后,一个模拟例子被给说明建议结果的有效性。 展开更多
关键词 二维离散系统 控制方法 计算方法 自动化技术 智能系统
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Stability Analysis of Continuous-time Iterative Learning Control Systems with Multiple State Delays 被引量:11
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作者 MENG De-Yuan JIA Ying-Min +1 位作者 DU Jun-Ping YU Fa-Shan 《自动化学报》 EI CSCD 北大核心 2010年第5期696-703,共8页
关键词 连续系统 稳定性 自动化 TDS
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Sliding mode H_∞ control for a class of uncertain nonlinear state-delayed systems 被引量:4
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作者 Wu Ligang Wang Changhong Gao Huijun Zhang Lixian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期576-585,共10页
A new proportional-integral (PI) sliding surface is designed for a class of uncertain nonlinear state-delayed systems. Based on this, an adaptive sliding mode controller (ASMC) is synthesized, which guarantees the... A new proportional-integral (PI) sliding surface is designed for a class of uncertain nonlinear state-delayed systems. Based on this, an adaptive sliding mode controller (ASMC) is synthesized, which guarantees the occurrence of sliding mode even when the system is undergoing parameter uncertainties and external disturbance. The resulting sliding mode has the same order as the original system, so that it becomes easy to solve the H∞ control problem by designing a memoryless H∞ state feedback controller. A delay-dependent sufficient condition is proposed in terms of linear matrix inequalities (LMIs), which guarantees the sliding mode robust asymptotically stable and has a noise attenuation level γ in an H∞ sense. The admissible state feedback controller can be found by solving a sequential minimization problem subject to LMI constraints by applying the cone complementary linearization method. This design scheme combines the strong robustness of the sliding mode control with the H∞ norm performance. A numerical example is given to illustrate the effectiveness of the proposed scheme. 展开更多
关键词 sliding mode control H∞ control NONLINEARITY state-delayed system linear matrix inequality (LMIs)
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Robust Delay-dependent H∞ Consensus Control for Multi-agent Systems with Input Delays 被引量:2
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作者 LI Zhen-Xing JI Hai-Bo 《自动化学报》 EI CSCD 北大核心 2014年第11期2556-2562,共7页
关键词 多代理系统 控制输出 时滞相关 延迟 输入 状态反馈控制器 线性化算法 不确定性
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H∞ Tracking Control for Switched LPV Systems With an Application to Aero-Engines 被引量:7
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作者 Kongwei Zhu Jun Zhao Georgi M.Dimirovski 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第3期699-705,共7页
This paper focuses on the H_∞ model reference tracking control for a switched linear parameter-varying(LPV)model representing an aero-engine. The switched LPV aeroengine model is built based on a family of linearized... This paper focuses on the H_∞ model reference tracking control for a switched linear parameter-varying(LPV)model representing an aero-engine. The switched LPV aeroengine model is built based on a family of linearized models.Multiple parameter-dependent Lyapunov functions technique is used to design a tracking control law for the desirable H_∞ tracking performance. A control synthesis condition is formulated in terms of the solvability of a matrix optimization problem.Simulation result on the aero-engine model shows the feasibility and validity of the switching tracking control scheme. 展开更多
关键词 Aero-engine control H_∞ tracking control multiple parameter-dependent Lyapunov functions switched linear parameter-varying(LPV) systems
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Fault-tolerant control of linear uncertain systems using H∞ robust predictive control 被引量:2
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作者 Chen Xueqin Geng Yunhai Zhang Yingchun Wang Feng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期571-577,共7页
The robust fault-tolerant control problem of linear uncertain systems is studied. It is shown that a solution for this problem can be obtained from a H∞ robust predictive controller (RMPC) by the method of linear m... The robust fault-tolerant control problem of linear uncertain systems is studied. It is shown that a solution for this problem can be obtained from a H∞ robust predictive controller (RMPC) by the method of linear matrix inequality (LMI). This approach has the advantages of both H∞ control and MPC: the robustness and ability to handle constraints explicitly. The robust closed-loop stability of the linear uncertain system with input and output constraints is proven under an actuator and sensor faults condition. Finally, satisfactory results of simulation experiments verify the validity of this algorithm. 展开更多
关键词 RMPC linear matrix inequality H∞ control fault-tolerant control.
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Robust H_∞ control for discrete-time polytopic uncertain systems with linear fractional vertices 被引量:2
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作者 ShaoshengZHOU JamesLAM ShengyuanXU 《控制理论与应用(英文版)》 EI 2004年第1期75-81,共7页
The robust H∞ control problem for discrete-time uncertain systems is investigated in this paper. The uncertain systems are modelled as a polytopic type with linear fractional uncertainty in the vertices. A new linear... The robust H∞ control problem for discrete-time uncertain systems is investigated in this paper. The uncertain systems are modelled as a polytopic type with linear fractional uncertainty in the vertices. A new linear matrix inequality (LMI) characterization of the H∞ performance for discrete systems is given by introducing a matrix slack variable which decouples the matrix of a Lyapunov function candidate and the parametric matrices of the system. This feature enables one to derive sufficient conditions for discrete uncertain systems by using parameter-dependent Lyapunov functions with less conservativeness. Based on the result, H∞ performance analysis and controller design are carried out. A numerical example is included to demonstrate the effectiveness of the proposed results. 展开更多
关键词 Discrete-time systems H∞ control Linear matrix inequality Uncertain systems
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Real-time Feed-forward Force Compensation for Active Magnetic Bearings System Based on H∞ Controller 被引量:11
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作者 GAO Hui XU Longxiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第1期58-66,共9页
There are two kinds of unbalance vibrations—force vibration and displacement vibration due to the existence of unbalance excitation in active magnetic bearings(AMB) system. And two unbalance compensation methods—c... There are two kinds of unbalance vibrations—force vibration and displacement vibration due to the existence of unbalance excitation in active magnetic bearings(AMB) system. And two unbalance compensation methods—closed-loop feedback and open loop feed-forward are presented to reduce the force vibration. The transfer function order of the control system directly influencing the system stability will be increased when the closed-loop method is adopted, which makes the real-time compensation not easily achieved. While the open loop method would not increase the primary transfer function order, it provides conditions for real-time compensation. But the real-time compensation signals are not easy to be obtained in the open loop method. To implement real-time force compensation, a new method is proposed to reduce the force vibration caused by the rotor unbalance on the basis of AMB active control. The method realizes real-time and on-line force auto-compensation based on H∞ controller and one novel feed-forward compensation controller, which makes the rotor rotate around its inertia axis. The time-variable feed-forward compensatory signal is provided by a modified adaptive variable step-size least mean square(VSLMS) algorithm. And the relevant least mean square(LMS) algorithm parameters are used to solve the H∞ controller weighting functions. The simulation of the new method to compensate some frequency-variable and sinusoidal signals is completed by MATLAB programming, and real-time compensation is implemented in the actual AMB experimental system. The simulation and experiment results show that the compensation scheme can improve the robust stability and the anti-interference ability of the whole AMB system by using H∞ controller to achieve close-loop control, and then real-time force unbalance compensation is implemented. The proposed research provides a new control strategy containing real-time algorithm and H∞ controller for the force compensation of AMB system. And the stability of the control system is finally improved. 展开更多
关键词 active magnetic bearings H∞ robust controller sensitivity and complementary sensitivity VSLMS algorithm feed-forward compensation
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