基于双滑模控制的PMSS直接转矩调速系统设计

Design of PMSS direct torque control system based on double sliding mode control

针对永磁同步电主轴传统直接转矩控制策略存在较大的磁链和转矩脉动,系统在低速段难以精确控制,以及由于磁链和转矩脉动引起的噪声和抖动等问题,该文提出了基于双滑模变结构控制的永磁同步电主轴直接转矩调速控制方案。提出通过转矩和磁链的2个滑模控制器来代替传统直接转矩中的2个滞环控制器,其输出实现了空间电压矢量调制,保证了逆变器开关频率恒定,减小了磁链和转矩脉动;分析滑模变结构控制所产生抖振缺陷的机理,选择适当的趋近律在保证系统鲁棒性的前提下有效抑制了抖振。实验和仿真结果表明,该调速系统具有动态响应快,磁链和转矩脉动小以及较强的鲁棒性等优点。

In view of the large magnetic chain and torque ripple in the traditional direct torque control strategy of permanent magnet spindle,the system is difficult to accurately control at the low speed section,and the noise and jitter caused by the magnetic chain and torque ripple,the direct torque control scheme of the permanent magnet synchronous motor spindle based on the dual sliding mode variable structure control is proposed.In this paper,two sliding mode controllers of torque and magnetic chain are put forward to replace two hysteresis controllers in traditional direct torque.Their output is modulated by space voltage vector,which ensures that the switching frequency of the inverter is constant and reduces the fluctuation of magnetic chain and torque,and the mechanism of chattering defect produced by sliding mode variable structure control is analyzed.The proper reaching law can effectively suppress chattering under the premise of ensuring the robustness of the system.The experimental and simulation results show that the speed regulation system has the advantages of fast dynamic response,small flux linkage and torque ripple,and strong robustness.