永磁同步电机双滑模无传感器矢量控制研究

Research on Dual Sliding Mode Sensor-Free Vector Control of Permanent Magnet Synchronous Motor

针对传统永磁同步电机(PMSM)无速度传感器控制系统存在高频抖动、低速失效、转速和转子位置估计差等问题,提出一种基于永磁同步电机的双滑模控制方法.首先,基于永磁同步电机数学模型构建闭环控制系统,引入含有边界层的双曲正切函数替代传统滑模控制器的开关函数,减少系统的高频抖动;其次,采用锁相环(PLL)提取转子位置和转速信息,提高检测精度;最后,设计一种滑模控制器来替代PI速度外环,增强系统的鲁棒性,减少外界干扰.Simulink仿真结果表明,采用滑模控制的速度外环相较于PI控制具有更好的动态性能,改进后的系统有效提升了系统跟踪精度,使电机在全速段可以保持良好的估算性能.

Aiming at the problems of high-frequency jitter,low-speed failure,poor speed and rotor position estimation in the traditional permanent magnet synchronous motor(PMSM)speed sensor-free control system,a dual sliding mode control method based on permanent magnet synchronous motor was proposed.Firstly,a closed-loop control system was built based on the mathematical model of the permanent magnet synchronous motor,the hyperbolic tangent function with boundary layer was introduced to replace the switching function of traditional sliding mode controller to reduce high frequency jitter.Secondly,phase-locked loop was used to extract rotor position and speed information to improve detection accuracy.Finally,a sliding mode controller was designed to replace the PI speed outer loop,which enhanced the robustness of the system and reduces external interference problems.Simulink simulation results showed that the speed outer loop using sliding mode control had better dynamic performance than PI control.The improved system effectively improved the tracking accuracy of the system,so that the motor can maintain good estimation performance at full speed.