带负载观测的感应电机动态分数阶滑模控制

为提高感应电机矢量控制性能,根据积分滑模控制和分数阶微积分理论,提出动态分数阶滑模控制方法。针对负载扰动问题,设计负载转矩滑模观测器,将负载观测值反馈到动态分数阶滑模控制中。通过Lyapunov定理证明所设计的控制器和观测器的稳定性和收敛性。仿真实验表明:负载观测器能准确观测负载转矩,带负载观测的动态分数阶滑模控制具较好的动态性能,对负载扰动有较强的鲁棒性,并有效抑制了滑模控制的抖振。     

基于ISTSMC和改进EKFSMO的PMSM无传感器矢量控制

在采用内环矢量控制(Field orientation control,FOC)和外环经典比例积分(Proportional integral,PI)控制的永磁同步电机(Permanent magnet synchronous motor,PMSM)驱动系统中,容易出现外部扰动检测精度低、抖振、速度环超调大等不确定性缺陷。为了解决PI控制的抖振缺点,提高系统抗干扰性,提出了一种积分超螺旋滑模控制(Integral super twisting sliding mode controller,ISTSMC)。为了实现无位置传感器控制以及电机转速与位置的在线估计,采用基于扩展卡尔曼滤波(Extended Kalmanfilter,EKF)的滑模观测器,并且设计了一种分段正弦型函数代替传统的基于sgn函数的滑模观测器降低抖振现象。在Matlab/Simulink仿真下,分析了该系统在各种故障扰动、反转运行和负载扰动下的速度响应和检测精度能力。结果证明了所提系统的可行性以及优越的动态性能。     

比例积分型线性超螺旋算法滑模观测器的感应电机无传感器控制

在无速度传感器感应电机调速系统中,针对滑模观测器存在滑模抖振与观测精度间的平衡问题,设计一种强鲁棒性的比例积分型线性超螺旋算法滑模观测器。首先,利用李雅普诺夫理论证明线性超螺旋算法的稳定性。然后,通过设计转子磁链观测器的中间变量,建立基于定子电流误差项的比例积分滑模面,构造出新的滑模磁链观测器。仿真与实验表明,该观测器有效抑制了滑模抖振,提升了电机的磁链观测与抗扰动能力,在电机运行时有较高的观测精度,提高了系统的动稳态性能。     

基于混合积分终端滑模的超级电容有限时间平抑电压波动方法

提出一种基于混合积分终端滑模的超级电容平抑电压波动方法,提高直流母线电压的收敛速度和抗干扰性。利用有限时间控制手段,引入最终吸引子,设计超级电容滑模面中的误差积分项为误差积分和带有分数幂误差积分线性组合的混合积分项,并证明这种混合积分滑模面具有有限时间收敛性能。仿真表明,基于混合积分终端滑模控制方法的超级电容平抑电压波动方法具有更快的收敛速度和更强的抗干扰性能,保证直流母线在有限时间内稳定。     

基于复合控制的三电平逆变器驱动PMSM的MPTC

针对三电平逆变器驱动永磁同步电机(PMSM)系统,提出基于复合控制的模型预测转矩控制策略(MPTC)。为减小转矩和磁链脉动,提高系统的控制性能,给出系统的MPTC方法。为克服扰动负载转矩的影响、增强系统的鲁棒性,分别设计负载扰动扩展观测器和基于幂函数的滑模转速调节器,在此基础上构造出复合控制器。通过对比基于PI转速调节器的三电平逆变器驱动系统与基于复合控制的三电平逆变器驱动系统,所提出的基于扰动负载观测器与改进滑模趋近律的复合控制策略能使PMSM稳定高效运行,并减小转矩脉动和三相定子电阻电流的THD值。仿真结果验证该方法控制的电机系统可稳定运行,进而验证该策略的正确性和有效性。     

有源电力滤波器神经终端滑模控制

以电力电子装备为接口的高渗透率可再生能源并网已成为未来配电网的显著特性。可再生能源具有随机性和间歇性,作为其并网接口的电力电子装备也会导致电能质量恶化等问题。为提高电能质量,该文提出一种有源电力滤波器神经终端滑模控制方法。首先,结合分数阶思想和滑模控制理论设计一种分数阶终端滑模控制器,以保证误差有限时间收敛,并引入边界层技术降低抖振。然后,利用自组织模糊神经网络构造一种无模型控制方案以更好地应对各种不确定因素。所设计的自组织模糊神经网络控制器用于学习分数阶终端滑模控制器,不仅从根源上解决抖振问题,而且可继承原控制器的有限时间收敛性能,并满足李雅普诺夫理论框架下的稳定控制性能。仿真与实验结果表明：所提出的控制方法能有效解决可再生能源发电系统中的谐波问题。     

基于ESO的PMSM驱动系统单相电流传感器模型预测转矩控制

针对仅有一相电流传感器的三相永磁同步电机(PMSM)系统,采用扩张状态观测器(ESO)技术构造观测器,以实现对其他两相电流和时变定子电阻的快速准确估计;为增强系统鲁棒性,设计改进滑模(SM)转速调节器;为减小转矩和磁链脉动,给出系统有限集-模型预测转矩(FS-MPTC)设计方法。所设计基于ESO的SM-MPTC策略能够使仅有一相电流传感器的PMSM系统可靠稳定运行,具有满意的动态性能和较强的鲁棒性。仿真结果验证了所提方法的正确性和可行性。     

燃气锅炉主汽压的RBF神经网络滑模控制策略设计

针对燃气锅炉主汽压控制的非线性、干扰大和模型参数易变的特点,常规比例积分微分(PID)控制方法难以取得满意的控制效果.利用滑模控制对系统参数变化和扰动不灵敏的优点,提出一种基于神经网络和滑模控制相结合的主汽压优化控制策略.采用径向基函数(RBF)神经网络调节滑模控制器的切换增益以降低其在平衡点的抖振,并通过在系统中设计干扰观测器实现对扰动的补偿.结果表明:与常规滑模控制和常规PID控制相比,不同工况下本文提出的控制策略超调量最多减少6.62％,调节时间最多减少57.45 s,且系统抖振小,跟随性能、抗干扰能力和鲁棒性能良好;工程实例表明,采用所提控制策略后,系统抖振比常规滑模控制降低33％,主汽压波动范围在-0.04～0.1 MPa,控制系统抗干扰能力得到显著提高.     

光伏LCL型并网逆变器的积分滑模容错控制策略

针对光伏LCL滤波并网逆变系统中参数的不确定性故障和外界干扰故障,对系统在不确定性和执行器故障情况下的数学模型进行重构,提出一种基于高阶滑模观测器的连续积分滑模容错控制方法,该算法设计一个高阶滑模状态观测器,可对故障状态进行有效估计,以抑制故障的不利影响。结合滑模控制原理构建一个连续积分滑模控制器,设计系统控制分配律,并推导出系统故障的稳定条件,采用Lyapunov函数证明闭环系统的稳定性。通过仿真验证所提控制策略的有效性。     

基于Luenberger滑模观测器的气缸压力估计

针对SI发动机模型中存在的参数扰动和不确定性问题,基于发动机非线性状态方程,设计了Luenberger滑模观测器。利用Lyapunov稳定性定理和滑模理论,分别设计合适的Luenberger增益和滑模增益,同时证明观测器误差系统稳定收敛。仿真结果表明:所设计的观测器不仅能够很好地处理系统存在的不确定性和参数扰动,加快跟踪速度,同时具有较高的估计精度。     

Fractional‐order sliding mode control for damping of subsynchronous control interaction in DFIG‐based wind farms

This paper proposes a fractional‐order sliding mode control (FOSMC) based on feedback linearization (FL) technique to mitigate subsynchronous control interaction (SSCI) in doubly fed induction generator (DFIG)–based wind farms connected to series‐compensated transmission lines. A linearized form of the studied system is obtained with the use of FL, which leads to reduced system order and small computational burden. Then the FOSMC is designed for grid‐side converter (GSC) to stabilize SSCI and to provide a considerable robustness against external disturbances and parameter uncertainties. For FOSMC parameter tuning, genetic algorithm (GA) is performed through MATLAB/SIMULINK. Time‐domain simulation are carried out to evaluate the effectiveness of the FOSMC in mitigating SSCI at varied operating conditions, and the superior performance of the proposed control is demonstrated as compared with conventional vector control (VC), feedback linearization sliding mode control (FLSMC), high‐order sliding mode control (HOSMC).     

载荷优化的海上漂浮式风电机组二阶滑模变桨控制

针对强非线性、强耦合的海上漂浮式风电机组动力学系统,提出一种基于二阶滑模的统一变桨控制策略,解决受海浪风速等随机干扰引起浮式支撑平台运动而产生的疲劳结构载荷及功率波动问题。构建漂浮式风电机组的不确定仿射非线性模型,基于风电机组“额定转速”设计积分滑模面,此“额定转速”不再是恒定值,而是取决于平台纵摇速度的变量,基于超螺旋算法实现二阶滑模变桨控制律。采用FAST和Matlab/Simulink联合仿真,所提出的方案与传统PI控制相比,对稳定高风速时风力发电机功率,抑制浮式支撑平台运动及减少叶根载荷具有更好的控制作用,对塔基也有较好的减载作用。     

Robust SVM-direct torque control of induction motor based on sliding mode controller and sliding mode observer

This paper proposes a design of control and estimation strategy for induction motor based on the variable structure approach. It describes a coupling of sliding mode direct torque control (DTC) with sliding mode flux and speed observer. This algorithm uses direct torque control basics and the sliding mode approach. A robust electromagnetic torque and flux controllers are designed to overcome the conventional SVM-DTC drawbacks and to ensure fast response and full reference tracking with desired dynamic behavior and low ripple level. The sliding mode controller is used to generate reference voltages in stationary frame and give them to the controlled motor after modulation by a space vector modulation (SVM) inverter. The second aim of this paper is to design a sliding mode speed/flux observer which can improve the control performances by using a sensorless algorithm to get an accurate estimation, and consequently, increase the reliability of the system and decrease the cost of using sensors. The effectiveness of the whole composed control algorithm is investigated in different robustness tests with simulation using Matlab/Simulink and verified by real time experimental implementation based on dS pace 1104 board.     

SSCI mitigation of grid‐connected DFIG wind turbines with fractional‐order sliding mode controller

To mitigate subsynchronous control interaction (SSCI) in doubly fed induction generator (DFIG)‐based wind farm, this paper proposes a robust controller for rotor‐side converter (RSC) using fractional‐order sliding mode controller (FOSMC). The proposed FOSMC can improve robustness and convergence properties of the controlled system, thus achieving SSCI damping under various operating conditions. Impedance‐based analysis and time‐domain simulation are performed to check the capability of the designed FOSMC as compared with conventional sliding mode control (SMC) and subsynchronous damping control (SSDC). Simulation results demonstrate that FOSMC can mitigate SSCI within shorter time and effectively reduce the fluctuation range of system transient responses under various operating conditions of wind speeds and compensation levels. Moreover, FOSMC also improves system robustness against parameter uncertainties and external disturbances, which is important for safe operation of realistic wind farms.     

Disturbance observer‐based integral sliding mode control for wind energy conversion systems

Recently, wind power production has been under the focus in generating power and became one of the main sources of alternative energy. Generating of maximum power from wind energy conversion system (WECS) requires accurate estimation of aerodynamic torque and uncertainties presented in the system. The current paper proposed the generalized high‐order disturbance observer (GHODO) with integral sliding mode control (ISMC) for extraction of maximum power via variable speed wind turbine by accurate estimation of wind speed. The assumption in previous works that considers the aerodynamic torque as slow‐varying is not applicable for the real system. Therefore, the high‐order disturbance observers were designed for precise estimation of uncertainties with fast‐changing behavior. A robust control system was designed to control the speed of the rotor at the optimal speed ratio. The obtained simulation results have shown the better performance characteristics than conventional linear quadratic regulator (LQR) approach. The stability of the proposed algorithm was proven by Lyapunov stability anaysis. Simulations results were obtained in Matlab/Simulink environment.     

基于扰动观测的漂浮式海上风力机主动滑模结构控制研究

针对漂浮式海上风力机主动结构控制问题,提出一种基于扰动观测的主动滑模控制方法,并应用风力机仿真工具FAST验证所提方法的有效性。在扰动二阶导数有界的前提下,理论证明观测器的稳定性和估计误差的有界性,从而有效估计匹配扰动和非匹配扰动。理论证明一类积分型滑模面的有限时间收敛性和闭环系统稳定性。基于FAST的仿真表明：所提出的主动调谐质量阻尼器（TMD）控制方法与最优被动TMD相比,主动TMD系统的漂浮平台俯仰角度和塔顶位移的均方根值可分别降低11.88%和13.56%,有效提升了风力机承受风浪载荷的能力。     

基于分数阶滑模和扩张状态观测器的励磁控制器设计

针对具有励磁控制的单机无穷大系统大干扰与小干扰响应不宜同时得到很好抑制的问题,在单机无穷大系统模型的基础上,利用分数阶微滑模理论构造李雅普诺夫稳定函数,并引入扩张状态观测器消除李雅普诺夫稳定函数的非线性项,以同时抑制大干扰和小干扰所引起的系统偏差。在Matlab/Smulink仿真平台上与AVR+PSS法分别进行仿真试验表明,该方法与AVR+PSS法相比,改善了系统的性能。     

永磁直驱风力发电机自抗扰技术及其无位置传感器控制策略

针对永磁直驱风力发电机传统矢量控制动态性能差,抗扰动能力弱的问题,提出一种双环线性自抗扰控制系统。在此基础上针对传统滑模观测器抖振等因素造成的速度和位置角观测误差较大的问题,提出改进型自适应滑模观测器。结果表明所设计的速度和电流双环线性自抗扰控制策略能有效提高转速跟踪性能和电流波形质量;在滑模观测器的基础上结合自适应算法精确观测反电动势,借鉴锁相环原理代替反正切函数估算出转子转速和位置角,相比传统滑模观测器具有更高的估算精度。