基于立方型转矩分配函数的SRM直接转矩控制-《郑州大学学报(工学版)》

文章信息/Info

Title:: Direct Torque Control of Switched Reluctance Motor ba＜x＞sed on Cubic Torque Distribution Function

Author(s):: Bai Guochang; Wu He Song; Zheng Peng;; School of Mechanical and Power Engineering, Zhengzhou University;

Keywords:: Switch magnetic resistance motor; torque pulse; direct torque control; torque distribution function; sector segmentation

摘要:: 开关磁阻电机具有结构简单、成本低廉、启动转矩大等优点，但也存在转矩脉动大的缺点。直接转矩控制用于开关磁阻电机虽能降低转矩脉动，但在换相期间存在转矩失控现象，为了避免这种失控现象的发生，需对开关磁阻电机的直接转矩控制进行优化。提出将立方型转矩分配函数与直接转矩控制相结合，其中转矩分配函数以合成瞬时转矩恒定为目标，利用其分配各相在不同位置的期望转矩，通过转矩滞环控制使合成瞬时转矩跟踪由速度闭环控制器输出的指令转矩，以实现均衡换相，从而抑制转矩脉动，并对传统的直接转矩控制6扇区进行细分，通过增加过渡电压矢量对开关表进行优化，结合磁链和转矩双滞环的控制方法避免了转矩失控，最后对控制方法进行数字仿真和实验验证。结果表明：当电机转速达到3 000 r/min，负载转矩为1 N·m时，转矩脉动由原来的112.02%降低至23.32%；当负载转矩为1.5 N·m时，转矩脉动由原来的65.25%降低至34.62%，SRM的转矩脉动小于直接转矩控制的转矩脉动。

Abstract:: Switched reluctance motor (SRM)has the advantages of simple structure,low cost and large starting torque, but it also has the disadvantage of large torque ripple.Direct torque control can reduce torque ripple of SRM,but there is torque runaway during commutation. In order to avoid it, it is necessary to optimize the direct torque control of SRM.The paper proposed that the cubic torque sharing function is combined with direct torque control,which aims at synthesizing constant instantaneous torque and distributes the desired torque of each phase in different positions.Through torque hysteresis control, the synthetic instantaneous torque is tracked to the command torque output by the speed closed-loop controller to achieve balanced phase commutation and thus suppress torque ripple,and subdivide six sectors of of traditional direct torque control.Switch tables are optimized by adding transition voltage vectors, and torque runaway is avoided by combining magnetic li＜x＞nk and torque double hysteresis control methods.Finally, the control method is verified by digital simulation and experiment.The results show that when the motor speed reaches 3 000 r/ min and the load torque is 1 N·m, the torque ripple is reduced from 112.02% to 23.32%When the load torque is 1.5 N·m,the torque ripple is reduced from 65.25% to 34.62%. The torque ripple of SRM is less than that of direct torque control.