基于超螺旋二阶滑模的PMSM-DTC系统研究

摘要

针对传统永磁同步电机直接转矩控制系统(PMSM-DTC)易受参数变化影响及转矩脉动大的问题,提出在系统中采用空间电压矢量调制技术(SVPWM)代替传统的正弦脉宽调制(SPWM),引入控制率为超螺旋算法的二阶滑模变结构,以定子磁链和转矩作为被控对象设计控制器代替传统系统中的PI控制器.仿真结果表明,该策略不仅有效消除了一阶滑模存在的抖振问题,明显减小了系统中定子磁链和转矩脉动,且具有较强的速度跟踪能力,对负载扰动和参数变化等不确定性具有很强的鲁棒性,因此可以很好地应用在电机控制方面.%Aiming at the problems that the conventional permanent magnet synchronous motor direct torque control system (PMSM-DTC) is susceptible to the influence of parameter change and torque ripple,it is proposed that the space voltage vector modulation technique (SVPWM) is used instead of the traditional sinusoidal pulse width modulation (SPWM),on the basis of which the second-order sliding mode variable structure control rate with super-twising algorithm is introduced,with the stator flux linkage and torque as the controlled object to design the controller instead of traditional PI controller in the system.The simulation results show that the strategy not only eliminates effectively the first-order sliding mode chattering problems,significantly reducing the stator flux linkage and torque ripple,but also has strong ability of speed tracking,with robustness to load disturbance,and parameter changes,etc.,therefore can be well applied in motor control.