The rotor-flux-oriented vector control for the permanent magnet synchronous motor (PMSM) requires accurate information of rotor position and speed as the feedback control signal to achieve the fast speed change in a wide range and the rejection in load disturbances. To deal with the characteristics of multivariable, nonlinearity and high-coupling in the mathematical model of PMSM, we develop a high-gain observer based on the nonlinear transformed observability canonical forms (NTOCF-HGO), and use it as the algorithm kernel to estimate the rotor position and speed. By using differential geometry theory to analyze the nonlinear local observability and global observability of the rotor-flux oriented model, we confirm the necessity of employing the nonlinear observer kernel in estimating the local and global states. In the comparison with another nonlinear observer kernel, the simulation results confirm the realization of the proposed nonlinear observer kernel in estimating the quadrature current, direct-axis current and the rotor speed. All these work provide potential support, from the theoretical and the algorithmic aspects, for the practical applications of this nonlinear observer kernel to PMSM sensorless vector control for realizing the stable start-up, state-estimation and the cross-convergence of the algorithm for position estimation.%永磁同步电机调速系统的矢量控制建立在转子磁链定向系内,为了获得优异的转速响应特性、调速范围,特别是低速调速性能及抗负载扰动性能等控制效果,需要获取转子精确的位置及速度信息作为反馈调节量.针对永磁同步电机模型方程多变量、非线性、强耦合的特点,设计了一种基于非线性坐标变换后能观测规范形的高增益观测器,将其作为转子位置及速度高精度估计的内核算法.基于微分几何理论分析了转子磁链定向系内模型的非线性局部弱能观性及全局能观性,从而肯定了应用非线性观测器内核进行局部及全局状态估计的必要性；与另一种不同内核的观测器相比较,数值仿真结果肯定了本文提出的非线性观测器内核在估计转子磁链定向系的交(直)轴电流及速度信息方面的可实现性.这样,在理论及算法两个方面,都证明了所提出的非线性观测器内核可以实现无传感器稳定起动、状态估计以及结合位置估算的算法交联收敛性.
展开▼
