变转速风力机额定风速以上的非线性控制 ——恒功率输出控制问题

讨论了额定风速以上时变转速风力机的控制问题，系统采用基于微分几何理论下的浆距角和触发角双输入控制，变转 速风机是一个带有大范围风速的多输入产多输出 非线性系统，通过坐标变换，使非线性系统转化为一个标准的线性系统。  

变速风力发电机故障观测器的设计和应用

针对模型包含未知非线性函数的变速风力发电机故障诊断问题,采用反卷法和最小二乘支持向量机对未知非线性函数进行辨识,将辨识结果作为补偿项加入比例高阶积分观测器中,消除未知非线性项对故障诊断精度的影响,建立了基于最小二乘支持向量机非线性项辩识模型的比例高阶积分故障观测器。李雅普诺夫函数证明该故障观测器的稳定性,仿真实验表明该故障观测器可以准确、快速、有效地诊断变速风力发电机故障。  

基于有效风速估计与预测的风电机组自适应最大风能跟踪控制

针对如何在有效风速未知情况下实现风电机组最大风能跟踪(MPPT)的问题,本文使用支持向量回归(SVR)和自适应控制原理,提出基于有效风速估计与预测的自适应MPPT控制方案.首先,使用机组的历史运行数据,训练得到基于SVR的风速估计与预测模型,为MPPT控制提供实时参考输入.其次,结合在线学习估计器(OLA)和减小转矩增益(DTG)控制原理,设计自适应MPPT控制器,该控制器能够较好应对系统未知动态特性和干扰,且能降低传动链载荷.最后,使用李雅普诺夫原理证明闭环系统所有信号都是有界的.仿真结果表明本文提出的方法能够获得良好的MPPT效果,进而提高机组产能.  

Adaptive Continuous Neural Pitch Angle Control for Variable‐Speed Wind Turbines

As wind energy becomes one of the fastest growing renewable energy resources, the control of large‐scale wind turbines remains a challenging task due to its system model nonlinearities and high external uncertainties. In this paper, an adaptive neural pitch angle control strategy is proposed for the variable‐speed wind turbines (VSWT) operating in pitch control region. The control objective is to maintain the rotor speed and generator power at the prescribed reference values in the presence of external disturbance, without the need of the information of system parameters and aerodynamics. First, the order of the system dynamics is increased by defining a filtered regulation error. By this means, the non‐affine characteristics of the VSWT model is transformed into a simple affine control problem and thus the feedback linearization technique can be employed. The continuousness of control signal is also guaranteed to relax the requirement on the bandwidth of actuators, and the mechanical load on pitching systems is reduced. Subsequently, an online learning approximator (OLA) is utilized to estimate the unknown nonlinear aerodynamics of the wind turbine and extend the practicability of the proposed adaptive parameter‐free controller. In addition, a high‐gain observer is implemented to obtain an estimation of rotor acceleration, which rejects the need of additional sensors. Rigid theoretical analysis guarantees the tracking of rotor speed/generator power and the boundedness of all other signals of the closed‐loop system. Finally, the effectiveness of the proposed scheme is testified via the Wind Turbine Blockset simulation package in Matlab/Simulink environment. Moreover, comparison results reveal that the introduced solution is able to provide better regulation performance than the conventional PI counterpart.  

Non-linear control of variable-speed wind turbines with permanent magnet synchronous generators: a robust backstepping approach

In this study, a robust backstepping approach for the control problem of the variable-speed wind turbine with a permanent magnet synchronous generator is presented. Specifically, to overcome the negative effects of parametric uncertainties in both mechanical and electrical subsystems, a robust controller with a differentiable compensation term is proposed. The proposed methodology ensures the generator velocity tracking error to uniformly approach a small bound where practical tracking is achieved. Stability of the overall system is ensured by Lyapunov-based arguments. Comparative simulation studies with a standard proportional-integral-type controller are performed to illustrate the effectiveness, feasibility and efficiency of the proposed controller.  

一类不确定变速风力涡轮机系统的实际跟踪控制

本文研究一类不确定变速风力涡轮机系统的实际跟踪控制问题. 与现有文献对系统不确定性和参考信号的严格限制(系统参数已知, 扰动光滑或上界已知, 参考信号二阶可导)不同, 本文允许系统参数全部未知, 扰动不必可导且上界不必已知, 参考信号仅需一阶可导, 因此传统控制设计方法无效. 为此, 本文首先给出误差系统, 将原系统的跟踪控制问题转化为误差系统的镇定控制问题. 然后, 对误差系统选择适当的李雅普诺夫函数, 将自适应动态补偿技术融入反推控制设计框架, 给出自适应状态反馈控制器显示形式. 性能分析表明该控制器保证闭环系统所有信号有界且转子转速实际跟踪到期望转速, 即在某个时刻之后到达并保持在期望转速的任意给定邻域内. 值得指出的是, 所设计的控制器仅依赖于参考信号本身而不依赖其导数, 因此降低了相关文献对参考信号可量测性的限制. 最后, 仿真实验验证理论结果的有效性.