Vienna整流器滑模直接功率及中点电位平衡控制策略

根据Vienna整流器的工作原理,建立基于开关函数的功率数学模型,在此基础上设计新型滑模直接功率控制策略,详细推导该控制算法,并给出具体设计过程;另外针对Vienna整流器存在中点电位波动和传统空间矢量调制计算繁琐等问题,提出基于载波调制的等效空间矢量调制算法,通过在载波调制中加入零序分量来等效空间矢量调制策略,同时在零序分量中加入平衡因子来控制中点电位平衡。滑模直接功率算法与等效空间矢量调制技术相结合可以实现开关定频和中点电位平衡,同时降低开关损耗,使Vienna整流器工作在近似单位功率因数下。最后搭建实验平台进行实验验证,结果表明:基于新型滑模直接功率控制策略和等效空间矢量调制算法相结合的Vienna整流器具有较好的鲁棒性和动态性能。

Sliding -mode based direct power control and neutral point potential balance control for Vienna rectifier

In this paper,according to the operation principle of Vienna-type rectifier,a direct power con-trol ( DPC) mathematics model based on switching functions is developed.The DPC based on sliding mode variable structure ( SMC-DPC) strategy is presented.The proposed control system diagram was deri-vate and the realized method was given.Aiming at the problems of the neutral point voltage unbalance and the complex space vector pulse width modulation ( SVPWM) ,a simplified equivalent space vector pulse width modulation ( ESVPWM) based on the carried-based pulse width modulation was proposed for this topology.It combines SMC-DPC and equivalent SVPWM technique together to achieve a constant switc-hing frequency and the midpoint potential balance,while the rectifier works with unity power factor and reduces the switching losses.Finally,this system was modeled and an experimental prototype was devel-oped,which illustrate that the combined SMC-DPC and ESVPWM strategy is easy to be designed and im-plemented with good robustness and dynamic performance.