一种永磁同步电机模型预测转矩控制简化策略研究

Study on a Simplified Strategy for Model Predictive Torque Control of Permanent Magnet Synchronous Motors

针对永磁同步电机传统模型预测转矩控制(MPTC)在线计算负担较大的问题,提出了一种MPTC简化策略。通过分析基本电压矢量在定子磁链不同扇区的利用率,舍弃利用率较小的电压矢量,减小备选电压矢量数量。并分析不同转矩误差绝对值下的零电压矢量的利用率,当转矩误差较小时,直接输出零电压矢量;当转矩误差较大时,舍弃零电压矢量,将备选电压矢量最大数量减小至4个。进一步,通过成本函数增加磁链误差约束,有效降低磁链脉动。仿真结果表明,与传统MPTC相比,所提简化控制策略可有效减少MPTC系统遍历次数,减轻计算负担,降低系统开关频率,且控制性能基本相当。

To address the issue of the heavy computational burden in traditional model predictive torque control(MPTC)for permanent magnet synchronous motors(PMSMs),a simplified MPTC strategy was proposed.By analyzing the utilization rates of basic voltage vectors in different stator flux linkage sectors,voltage vectors with lower utilization rates were discarded,thereby reducing the number of candidate voltage vectors.Additionally,the utilization of the zero-voltage vector under different absolute values of torque error was analyzed.When the torque error was small,the zero-voltage vector was directly applied;when the torque error was large,the zero-voltage vector was discarded,reducing the maximum number of candidate voltage vectors to four.Furthermore,a flux linkage error constraint was added to the cost function,effectively reducing flux linkage ripple.Simulation results showed that,compared to traditional MPTC,the proposed simplified control strategy effectively reduced the number of MPTC traversals,alleviated the computational burden,lowered the system’s switching frequency,and maintained similar control performance.