带中点电位平衡的VIENNA整流器反推控制研究

由于VIENNA整流器具有强耦合及非线性的特点，在建立VIENNA整流器d-q坐标系数学模型的基础上，采用反推控制策略实现对于直流电压以及d-q轴电流的控制。将基于两电平空间矢量脉宽调制SVPWM（space vector pulse width modulation）的简化算法移植到VIENNA整流器中，分析了VIENNA整流器SVPWM工作原理，并在此基础上采用软件算法调整P、N小矢量的作用时间，实现中点电位的平衡。最后，利用Matlab/Simulink软件搭建仿真平台，验证所提控制策略的合理性以及有效性。在中点电位平衡作用下，与传统的PI控制相比，反推控制增加了输出直流电压的稳定性，改善了电流谐波，并进一步提高了功率因数，使得VIENNA整流器有更好的动态响应性能。

Research on Backstepping Control of VIENNA Rectifier Based on Neutral-point Potential Balance

Owing to the strong coupling and non-linearity characteristics of a VIENNA rectifier, on the basis of establishing its d-q coordinate axis mathematical model, the backstepping control strategy is adopted to realize the control of DC voltage and d-q axis current. A simplified algorithm based on two-level space vector pulse width modulation(SVPWM) is transplanted into the VIENNA rectifier, and the working principle for the space vector modulation of the VIENNA rectifier is analyzed, based on which a software algorithm is used to adjust the action time of small vectors P and N to achieve the neutral-point potential balance. Finally, a simulation platform is built using Matlab/Simulink to verify the rationality and effectiveness of the proposed control strategy. Compared with the traditional PI control, the backstepping control increases the stability of output DC voltage, improves the current harmonics, and further improves the power factor under the neutral-point potential balance, which makes the VIENNA rectifier have a better dynamic performance.