为了更有效地控制舰船动力机械宽频和低频线谱振动的传递,提出了一种将磁悬浮作动器与气囊隔振器集成应用的磁悬浮-气囊主被动混合隔振装置。通过对磁悬浮作动器机电耦合特性和混合隔振系统动力学特性的分析研究,确定了满足线谱振动控...为了更有效地控制舰船动力机械宽频和低频线谱振动的传递,提出了一种将磁悬浮作动器与气囊隔振器集成应用的磁悬浮-气囊主被动混合隔振装置。通过对磁悬浮作动器机电耦合特性和混合隔振系统动力学特性的分析研究,确定了满足线谱振动控制要求和满足混合隔振装置性能要求的参数设计方法。针对主动控制时,FxLMS(filtered-x least mean square)算法在小阻尼系统上需用高阶FIR滤波器建模,运算量大的问题,提出了分频段控制的改进FxLMS算法,并有效地解决了作动器的非线性效应问题。样机实验结果表明:理论分析是正确的,该项技术控制力需求小,装置稳定性好,具有优良的宽频隔振和低频线谱振动控制效果。展开更多
Compared with traditional hydraulic actuators, an Electro-Mechanical Actuator(EMA)is small in size and light in weight, so it has become more widely used. Aerodynamic load on aircraft control surface varies dramatical...Compared with traditional hydraulic actuators, an Electro-Mechanical Actuator(EMA)is small in size and light in weight, so it has become more widely used. Aerodynamic load on aircraft control surface varies dramatically, and a change of flight environment leads to uncertainties of motor parameters. Therefore, high-dynamic response and strong anti-disturbance capability of an EMA are of great significance for aircraft rudder control and flight attitude adjustment. In order to improve dynamic response and disturbance rejection of an EMA and simplify control parameters tuning, a robust high-dynamic servo system based on Linear Active Disturbance Rejection Control(LADRC) is proposed for an EMA employing a Permanent Magnet Synchronous Motor(PMSM).Firstly, total disturbances of the EMA are analyzed, including parameter uncertainties, load variation, and static friction. A disturbance observer based on a reduced-order Extended State Observer(ESO) is designed to improve the anti-interference ability and dynamic performance. Secondly, the servo control architecture is simplified to a double-loop system, and a composite control of position and speed with acceleration feed-forward is presented to improve the EMA frequency bandwidth.Thirdly, the ideal model of the EMA is transformed into a simple cascade integral form with a disturbance observer, which makes it convenient to analyze and design the controller. Robustness performance comparisons are realized in frequency domain. Finally, simulation and experimental results have verified the effectiveness of the proposed strategy for EMAs.展开更多
Electromechanical actuators(EMAs) are becoming increasingly attractive in the field of more electric aircraft because of their outstanding benefits, which include reduced fuel burn and maintenance cost, enhanced sys...Electromechanical actuators(EMAs) are becoming increasingly attractive in the field of more electric aircraft because of their outstanding benefits, which include reduced fuel burn and maintenance cost, enhanced system flexibility, and improved management of fault detection and isolation. However, electromechanical actuation raises specific issues when being used for safetycritical aerospace applications like flight controls: huge reflected inertia to load, jamming-type failure, and increase of backlash with service due to wear and local dissipation of heat losses for thermal balance. This study proposes an incremental approach for virtual prototyping of EMAs. It is driven by a model-based system engineering process in order to enable simulation-aided design.Best practices supported by Bond graph formalism are suggested to develop a model's structure efficiently and to make the model ready for use(or extension) by addressing the above mentioned issues. Physical effects are progressively introduced, and the realism of lumped-parameter models is increased step-by-step. In particular, multi-level component models are architected to ensure continuity between engineering activities. The models are implemented in the AMESim simulation environment, and simulation responses are given to illustrate how they can be used for preliminary sizing, control design, thermal balance verification, and faults to failure analysis. The proposed best practices intend to provide engineers with fast, reusable, and efficient means to assess performance virtually and enhance maturity, performance, and robustness.展开更多
In the flight process of aircrafts, their electromechanical actuators(EMA) must have the ability of enduring uncertainties caused by factors such as load disturbance, the variation of work temperature and the EMA's...In the flight process of aircrafts, their electromechanical actuators(EMA) must have the ability of enduring uncertainties caused by factors such as load disturbance, the variation of work temperature and the EMA's nonlinearity. At present, in order to increase the EMA's robustness on the uncertainties, the H, control method has been applied in aircrafts. The major problems with standard H∞ control lie in the large overshoot of step response and the high orders of the controller. For the purpose of addressing the two problems, this paper investigates several kinds of robust control strategies of the EMA. A mathematical model of the EMA is first built, and then with MATLAB software a H∞ controller and an improved hybrid robust controller composed of a reduced order H∞controller and a lead compensator are designed. In order to make a scientific comparison of the control effects of H∞ controller, hybrid controller and classic proportion-integral-differential(PID) controller, a simulation research is made in respect of the open loop frequency response and the closed loop step response of the three controllers. For comparing the robustness of the three controllers, the load torque is entered as a disturbance and the disturbance response of error and control input are thus obtained. The experiments with the three controllers are also conducted. Through giving the EMA a command and a disturbance torque successively, the transient response and disturbing process of EMA are recorded. The simulation and experiment results show that with the help of the hybrid controller, the EMA not only guarantees good dynamic characteristics, but also has strong robustness of disturbance rejection. Therefore, the excogitated H∞ hybrid control method effectively solves the problem of large overshoot in dynamic response, and moderately meets the requirement of overcoming the uncertainties in the EMA of aircrafts.展开更多
文摘为了更有效地控制舰船动力机械宽频和低频线谱振动的传递,提出了一种将磁悬浮作动器与气囊隔振器集成应用的磁悬浮-气囊主被动混合隔振装置。通过对磁悬浮作动器机电耦合特性和混合隔振系统动力学特性的分析研究,确定了满足线谱振动控制要求和满足混合隔振装置性能要求的参数设计方法。针对主动控制时,FxLMS(filtered-x least mean square)算法在小阻尼系统上需用高阶FIR滤波器建模,运算量大的问题,提出了分频段控制的改进FxLMS算法,并有效地解决了作动器的非线性效应问题。样机实验结果表明:理论分析是正确的,该项技术控制力需求小,装置稳定性好,具有优良的宽频隔振和低频线谱振动控制效果。
基金supported by the Shaanxi Provincial Key R&D Program, China (No. 2017KW-ZD-05)the Natural Science Basic Research Plan in Shaanxi Province of China (No. 2018JQ5187)the Fundamental Research Funds for the Central Universities,China(Nos.3102017JC06004, 3102017OQD029)
文摘Compared with traditional hydraulic actuators, an Electro-Mechanical Actuator(EMA)is small in size and light in weight, so it has become more widely used. Aerodynamic load on aircraft control surface varies dramatically, and a change of flight environment leads to uncertainties of motor parameters. Therefore, high-dynamic response and strong anti-disturbance capability of an EMA are of great significance for aircraft rudder control and flight attitude adjustment. In order to improve dynamic response and disturbance rejection of an EMA and simplify control parameters tuning, a robust high-dynamic servo system based on Linear Active Disturbance Rejection Control(LADRC) is proposed for an EMA employing a Permanent Magnet Synchronous Motor(PMSM).Firstly, total disturbances of the EMA are analyzed, including parameter uncertainties, load variation, and static friction. A disturbance observer based on a reduced-order Extended State Observer(ESO) is designed to improve the anti-interference ability and dynamic performance. Secondly, the servo control architecture is simplified to a double-loop system, and a composite control of position and speed with acceleration feed-forward is presented to improve the EMA frequency bandwidth.Thirdly, the ideal model of the EMA is transformed into a simple cascade integral form with a disturbance observer, which makes it convenient to analyze and design the controller. Robustness performance comparisons are realized in frequency domain. Finally, simulation and experimental results have verified the effectiveness of the proposed strategy for EMAs.
基金supports of the China Scholarship Council(CSC)the National Natural Science Foundation of China(No.51275021 and No.61327807)
文摘Electromechanical actuators(EMAs) are becoming increasingly attractive in the field of more electric aircraft because of their outstanding benefits, which include reduced fuel burn and maintenance cost, enhanced system flexibility, and improved management of fault detection and isolation. However, electromechanical actuation raises specific issues when being used for safetycritical aerospace applications like flight controls: huge reflected inertia to load, jamming-type failure, and increase of backlash with service due to wear and local dissipation of heat losses for thermal balance. This study proposes an incremental approach for virtual prototyping of EMAs. It is driven by a model-based system engineering process in order to enable simulation-aided design.Best practices supported by Bond graph formalism are suggested to develop a model's structure efficiently and to make the model ready for use(or extension) by addressing the above mentioned issues. Physical effects are progressively introduced, and the realism of lumped-parameter models is increased step-by-step. In particular, multi-level component models are architected to ensure continuity between engineering activities. The models are implemented in the AMESim simulation environment, and simulation responses are given to illustrate how they can be used for preliminary sizing, control design, thermal balance verification, and faults to failure analysis. The proposed best practices intend to provide engineers with fast, reusable, and efficient means to assess performance virtually and enhance maturity, performance, and robustness.
基金supported by National Astronautic Foundation of China
文摘In the flight process of aircrafts, their electromechanical actuators(EMA) must have the ability of enduring uncertainties caused by factors such as load disturbance, the variation of work temperature and the EMA's nonlinearity. At present, in order to increase the EMA's robustness on the uncertainties, the H, control method has been applied in aircrafts. The major problems with standard H∞ control lie in the large overshoot of step response and the high orders of the controller. For the purpose of addressing the two problems, this paper investigates several kinds of robust control strategies of the EMA. A mathematical model of the EMA is first built, and then with MATLAB software a H∞ controller and an improved hybrid robust controller composed of a reduced order H∞controller and a lead compensator are designed. In order to make a scientific comparison of the control effects of H∞ controller, hybrid controller and classic proportion-integral-differential(PID) controller, a simulation research is made in respect of the open loop frequency response and the closed loop step response of the three controllers. For comparing the robustness of the three controllers, the load torque is entered as a disturbance and the disturbance response of error and control input are thus obtained. The experiments with the three controllers are also conducted. Through giving the EMA a command and a disturbance torque successively, the transient response and disturbing process of EMA are recorded. The simulation and experiment results show that with the help of the hybrid controller, the EMA not only guarantees good dynamic characteristics, but also has strong robustness of disturbance rejection. Therefore, the excogitated H∞ hybrid control method effectively solves the problem of large overshoot in dynamic response, and moderately meets the requirement of overcoming the uncertainties in the EMA of aircrafts.