基于改进滑模的永磁同步电机控制

Control of Permanent Magnet Synchronous Motor Based on Improved Sliding Mode

为提高永磁同步电机调速系统的控制性能,设计双闭环控制系统,电流反馈解耦PD作为电流环控制器,滑模控制器作为速度控制器.为解决传统指数趋近律的趋近速度与曲线抖振之间的矛盾,设计形状和幅值可调的双曲正切函数代替符号函数,减小符号函数跳变不连续产生的系统抖振;设计指数趋近律等速切换项参数模糊自整定算法和指数切换项参数分段自整定规则,不仅减小了高频抖振,也保证了滑动模态切换的稳定性.仿真试验结果显示:高速时,本文提出的策略在0.03秒实现了对期望转速的跟踪,调节时间减少了0.02 s,抖振幅度减少44,在负载突增时,动态速降低9 r/min;低速时,本文提出的策略与常规滑模控制调节时间差别不大,但抖振幅度依然比常规滑模控制小,在负载突增时,动态速降低8 r/min.

In order to improve the control performance of the speed control system of the permanent magnet synchronous motor,a dual closed-loop control system is designed,with the current feedback decoupling PD as the current loop controller and the sliding mode controller as the speed controller.To solve the contradiction of traditional exponential reaching law between the rapidity and chattering,a hyperbolic tangent function with adjustable shape and amplitude is designed to replace the symbol function,effectively avoid discontinuity of switching control caused by the symbol function.The fuzzy self-tuning algorithm and segmental self-tuning rules are used to regulate the equal-speed switching term and the exponential switching term in the exponential convergence law,respectively.It not only reduces the high-frequency shaking,but also ensures the stability of the sliding mode switching.The simulation verified the effectiveness of the proposed method.The results show that compared with the traditional sliding mode control at high speed,the proposed control strategy can track the desired speed within 0.03 s,the regulation time is reduced by 0.02 s,and the chattering amplitude is reduced by 44,the dynamic speed is small by 9 r/min with the sudden load increases.At low speed,there was little difference in the adjustment time between the proposed strategy and the traditional sliding mode control,the chattering amplitude is still smaller,the dynamic speed is small by 8 r/min.