三电平PWM整流器定频直接功率控制技术研究

摘要

Direct power control system has the characteristics of fast response and simple algorithms.The bang-bang control is used in the traditional DPC system,however,it has the disadvantages such as unset switching frequency. By combining the DPC control and space vector pulse width modulation(SVM) algorithm, the advantages of system are intensified, meanwhile, the drawback mentioned above is overcome.The decoupling control of active and reactive power in dynamic process is realized by SVM.Compared with the traditional control strategy,the proposed VF-DPC-SVM method guarantees a fixed switching frequency and realizes a better dynamic performance. Furthermore, the system has better dynamic characteristics.The simulation and experimental results show that the control method can achieve better dynamic effect and realize the decoupling of active and reactive power.%直接功率控制(DPC)具有响应快、算法简单的特点.传统的DPC采用bang-bang控制,存在开关频率不固定等缺点,将DPC控制与空间矢量脉宽调制(SVM)算法的思想相结合,两者的优势互补,同时克服了传统DPC开关频率不固定的缺点.利用矢量控制中SVM技术,实现了动态过程中有功功率和无功功率的解耦控制,相对于传统的DPC开关表控制方式,VF-DPC-SVM控制方法保证了固定开关频率,同时使系统具有较好的动态性能.仿真和实验结果表明,该控制方法动态效果较好,能够实现有功和无功功率的解耦.