Department of Mechanical and Electro-Mechanical Engineering, National Sun Yat-sen University, Kaohsiung 80424, Taiwan.
Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung 80424, Taiwan.
Sensors (Basel). 2020 Jun 3;20(11):3177. doi: 10.3390/s20113177.
This paper presents an improved control system for a small flux-switching permanent magnet motor (FSPM) to enhance its performance and torque sensing. The analytical magnetic circuit design was used to determine the related motor parameters, such as the air gap flux density, permeance coefficient (Pc), torque, winding turns, pole number, width, length, magnet geometry, and the current density of FSPM. The electromagnetic analysis of this motor was performed by software (ANSYS Maxwell) to optimize the motor performance. In this study, the performance of FSPM was investigated by the uniform design experimentation (UDE). For the control system, the model predictive current control (MPCC) is currently recognized as a high-performance control strategy, due to its quick response and simple principle. This model contained the nonlinear part of the system, to improve the torque ripple of FSPM. A modified MPCC strategy was proposed to improve the distortion of the current waveform and decrease the computational burden. The new modified control architecture was mainly composed of three parts, such as the estimation of electromotive force (EMF), current prediction, and optimal vector selection/vector duration. When the reference voltage vector was obtained, the three-phase duties were easily determined by the principle of space vector modulation (SVM). The results show the different strategy methods between the newly proposed modified MPCC and traditional proportional integral (PI) controller. In the control of FSPM, a modified MPCC strategy was able to achieve a better performance response and decrease the computational burden. At a low speed of 350 rpm, the proposed modified MPCC can achieve a better dynamic response. The nonlinear problem of the startup speed was also effectively resolved. The torque sensing performance of the simulation and the experimental test value were compared. The torque sensing performance of the simulation and the actual test value were also examined. In this study, the optimization focused not only on the motor design and fabrication, but also on an improved motor control strategy and torque sensing, in order to achieve the integrity of the FSPM system.
本文提出了一种改进的小磁通切换永磁电机（FSPM）控制系统，以提高其性能和转矩感测能力。采用解析磁路设计来确定相关电机参数，例如气隙磁通密度、导磁系数（Pc）、转矩、绕组匝数、极数、宽度、长度、磁铁几何形状和 FSPM 的电流密度。通过软件（ANSYS Maxwell）对该电机进行电磁分析，以优化电机性能。在本研究中，通过均匀设计实验（UDE）研究 FSPM 的性能。对于控制系统，模型预测电流控制（MPCC）由于其快速响应和简单原理，目前被认为是一种高性能控制策略。该模型包含系统的非线性部分，以改善 FSPM 的转矩纹波。提出了一种改进的 MPCC 策略来改善电流波形的失真并降低计算负担。新的改进型控制架构主要由三个部分组成，例如电动势（EMF）估计、电流预测和最优矢量选择/矢量持续时间。当参考电压矢量确定后，通过空间矢量调制（SVM）原理很容易确定三相占空比。结果表明，新提出的改进型 MPCC 和传统比例积分（PI）控制器之间存在不同的策略方法。在 FSPM 的控制中，改进的 MPCC 策略能够实现更好的性能响应并降低计算负担。在 350rpm 的低速下，提出的改进型 MPCC 可以实现更好的动态响应。启动速度的非线性问题也得到了有效解决。对仿真和实验测试值进行了转矩感测性能比较。还检验了仿真和实际测试值的转矩感测性能。在这项研究中，优化不仅集中在电机设计和制造上，还集中在改进的电机控制策略和转矩感测上，以实现 FSPM 系统的完整性。
