针对外部突加大负载扰动时,传统自抗扰控制策略中扩展状态观测器(ESO)的观测精度差,以及系统噪声对ESO观测精度的影响,提出一种基于卡尔曼滤波器的自抗扰控制策略(KF-ADRC).通过卡尔曼滤波器观测出的负载转矩进行前馈补偿,以提高大负载扰动下ESO观测精度;通过卡尔曼滤波器观测出的转速用作系统闭环反馈,以削弱系统噪声对ESO观测精度的影响.将传统自抗扰中的线性误差状态反馈律替换为非线性误差状态反馈律,以提升系统跟踪和抗扰性能.搭建了400 W PMSM伺服系统驱动平台验证了该控制策略的有效性.

This article proposes a rotor design method suitable for double-layer interior permanent magnet synchronous motor (DIPMSM), which can reduce electromagnetic torque ripple and at the same time reduce the electromagnetic noise of the motor. In previous studies, the inverse cosine function (ICF) was used to modify the rotor shape for making the air-gap flux density distribution sinusoidal under no-load conditions, which can reduce the torque ripple. However, conventional ICF can only be used in a single-layer interior rotor structure. Consequently, this article proposes a piecewise inverse cosine function (PICF) based on ICF, which can be applied to DIPMSM. To verify the improvement of the proposed method in the electromagnetic and noise aspects of the motor, the electromagnetic model and a noise prediction model of the 36-slot/8-pole motor are established by the finite element method. The PICF model is compared with the prototype in the aspects of electromagnetic performance and noise. The torque ripple is reduced by 54.16%, from ±2.4 to ±1.1 N m, and the electromagnetic noise is reduced by about 4.9 dB. Finally, the accuracy of the noise prediction model is verified by the noise test of the prototype.

This paper proposes a direct torque control (DTC) of permanent magnet synchronous motor (PMSM) with high torque estimation accuracy.Based on the PMSM mathematical model considering iron loss resistance, this paper analyzes that when using stator current to estimate torque, the accuracy will be affected by iron loss resistance.Using stator magnetizing current can solve the current deviation caused by iron loss resistance and improve torque estimation accuracy.Since the stator magnetizing current cannot be obtained directly, a novel iron loss resistance observer based on the model reference adaptive system (MRAS) is designed to estimate iron loss resistance and stator magnetizing current simultaneously.Popov's hyperstability theory guarantees the stability of the designed observer.Finally, a 1kW PMSM experimental platform is constructed to verify the proposed method.Both the simulation and experimental results show that the designed observer is stable, and using stator magnetizing current to estimate torque has better accuracy than stator current.

This study proposes a method to reduce the electromagnetic noise of a double-layer interior permanent magnet synchronous motor (DIPMSM) by optimising the flux barrier. First, a noise prediction model of the 36-slot/8-pole DIPMSM is established by finite element (FE). According to the simulation results, the noise of the motor is the loudest at 5000 rpm, especially with a noise component of 3333.3 Hz. From the results of modal analysis, it can be concluded that the four-order radial force with a frequency of 3333.3 Hz resonates with the stator, resulting in the loudest noise. Then, the source of the radial force that causes the loudest noise is analysed, and it can be found that the 9th and 11th harmonics of rotor magnetic motive force have the greatest contribution to the force. By optimising the rotor, the radial force contributed by the 9th and 11th harmonics is weakened, thereby reducing the noise caused by these harmonics. Finally, the electromagnetic performance and noise of the optimised motor are checked by FE. Compared with the initial rotor, the torque ripple is reduced by 26.79%, and noise is reduced by 5.542 dB. The noise test on the prototype verifies the accuracy of the noise prediction model.

针对传统采用线性反馈的自抗扰控制器在误差收敛速度方面的不足,结合自抗扰控制思想,采用扩张状态观测器和非线性误差状态反馈的复合型控制策略,利用扩张状态观测器(ESO)观测系统扰动并进行前馈补偿,再通过引入非线性误差状态反馈(NLESF)生成控制量,使系统能够兼顾跟踪性能和抗扰性能,提高误差收敛速度.给出线性反馈和非线性反馈的跟踪性能和抗扰性能的对比理论分析,通过仿真对比PI,P+ESO,NLESF+ESO三种控制方式,验证了NLESF+ESO的复合型结构具有更快的误差收敛速度和更强的抗扰性能.

针对传统无磁链环空间矢量调制直接转矩控制(SVM-DTC)定子磁链直轴分量不可控的问题,提出一种磁链预测的新型无磁链环SVM-DTC.该方法考虑了只施加交轴电压矢量带来的磁链幅值增加的问题,以及转子磁链位置变化带来的增磁效果.通过预测满足转矩控制要求并且定子电流直轴分量为零的目标定子磁链,精确计算出最优参考电压矢量.仿真结果表明,该方法可以同时控制定子磁链交直轴分量,定子磁链幅值随负载进行自适应变化.