The response of a nonlinear vibration system may be of three types, namely, periodic, quasiperiodic or chaotic,,when the parameters of the system are changed. The periodic motions can be identified by Poincare map, an...The response of a nonlinear vibration system may be of three types, namely, periodic, quasiperiodic or chaotic,,when the parameters of the system are changed. The periodic motions can be identified by Poincare map, and harmonic wavelet transform (HWT) can distinguish quasiperiod from chaos, so the existing domains of different types of motions of the system can be revealed in the parametric space with the method of HWT joining with Poincare map.展开更多
无刷直流电机(Brushless DC Motor,简称BLDCM)凭借高功率密度、高效能以及低维护费用等优势,在工业自动化、航空航天、电力巡检等多个领域被广泛采用[1]。不过,受其自身独特结构的制约,电机在运转过程中会产生以齿槽转矩为主导的非线性...无刷直流电机(Brushless DC Motor,简称BLDCM)凭借高功率密度、高效能以及低维护费用等优势,在工业自动化、航空航天、电力巡检等多个领域被广泛采用[1]。不过,受其自身独特结构的制约,电机在运转过程中会产生以齿槽转矩为主导的非线性干扰,这极大地阻碍了系统模型的精准辨识,进而对高性能控制算法的研发与应用造成限制。通过深入剖析了无刷直流电机非线性干扰对系统辨识产生的作用,进而提出一种借助小波包变换的开环辨识策略,以及一种基于虚拟对象建模的闭环辨识策略,达到提高无刷直流电机模型在非线性干扰环境下的辨识精度,通过仿真与实验验证,所提出的方法在不同工作点、不同干扰位置的情况下,均能大幅提升模型辨识的精准度。展开更多
文摘The response of a nonlinear vibration system may be of three types, namely, periodic, quasiperiodic or chaotic,,when the parameters of the system are changed. The periodic motions can be identified by Poincare map, and harmonic wavelet transform (HWT) can distinguish quasiperiod from chaos, so the existing domains of different types of motions of the system can be revealed in the parametric space with the method of HWT joining with Poincare map.
文摘无刷直流电机(Brushless DC Motor,简称BLDCM)凭借高功率密度、高效能以及低维护费用等优势,在工业自动化、航空航天、电力巡检等多个领域被广泛采用[1]。不过,受其自身独特结构的制约,电机在运转过程中会产生以齿槽转矩为主导的非线性干扰,这极大地阻碍了系统模型的精准辨识,进而对高性能控制算法的研发与应用造成限制。通过深入剖析了无刷直流电机非线性干扰对系统辨识产生的作用,进而提出一种借助小波包变换的开环辨识策略,以及一种基于虚拟对象建模的闭环辨识策略,达到提高无刷直流电机模型在非线性干扰环境下的辨识精度,通过仿真与实验验证,所提出的方法在不同工作点、不同干扰位置的情况下,均能大幅提升模型辨识的精准度。
