异步电机模型预测三电平直接电流控制

发布时间：2018-02-16 18:32

本文关键词： 三电平逆变器模型预测直接电流控制中点电压平衡开关频率延时补偿　出处：《电工技术学报》2017年18期 　论文类型：期刊论文

【摘要】：三电平逆变器为控制系统提供了更多的电压矢量,相对于传统两电平逆变器能够使得直接电流跟踪控制变得更加精确,能进一步减小电流纹波。但是三电平逆变器存在中点电压平衡问题,如果不对中点电压进行控制会使得电机无法正常工作,同时在大容量三电平逆变器中一般需要其降低开关频率。因此,提出一种具有中点电压平衡和降低开关频率功能的模型预测直接电流控制方案:通过对中点电压进行预测控制,在模型预测直接电流控制的价值函数中加入开关切换次数的约束,能将中点电压有效控制在给定的范围内,并同时实现逆变器开关频率的降低;针对控制延时导致定子电流在参考值附近振荡并增加电流纹波和转矩脉动,采用延时补偿提高控制系统性能。仿真和实验结果验证了所提方法的有效性和可行性。
[Abstract]:The three-level inverter provides more voltage vectors for the control system. Compared with the traditional two-level inverter, it can make the direct current tracking control more accurate. The current ripple can be further reduced. However, the three-level inverter has the problem of neutral point voltage balance. If the neutral voltage is not controlled, the motor will not work properly. At the same time, it is necessary to reduce the switching frequency in large capacity three-level inverter. Therefore, a model predictive direct current control scheme with the function of neutral voltage balance and switching frequency reduction is proposed. The switching frequency constraint is added to the value function to predict the direct current control. The midpoint voltage can be effectively controlled within a given range and the switching frequency of the inverter can be reduced at the same time. In view of the stator current oscillation near the reference value and the increase of current ripple and torque ripple, delay compensation is used to improve the performance of the control system. The simulation and experimental results show that the proposed method is effective and feasible.
【作者单位】：上海大学机电工程与自动化学院;
【基金】：国家自然科学基金(51377102) 国家重大科学仪器设备开发专项(2012YQ15008703)项目南通市应用基础研究项目(GY12016008)资助
【分类号】：TM343;TM464

【相似文献】