提出了一种串联型 Z-源双输出双级矩阵变换器(Z-source dual output two-stage matrix converter, ZS-DO-TSMC)拓扑及其调制策略,克服了传统 DO-TSMC电压传输比低、抗干扰能力弱、逆变级需要开关死区和开关器件多等缺点.拓扑电路由整流级、Z-源阻抗网络和五桥臂逆变级组成,可以同时输出2路独立的三相对称正弦电压.利用Z-源阻抗网络的升压特性,提出了一种动态Z-源升压系数的改进型空间矢量调制策略,通过动态调节直通矢量的占空比,实现 Z-源阻抗网络输出电压的恒定,提高逆变级的调制系数、降低 Z-源电容电压应力.仿真和实验验证了所提拓扑和调制策略的正确性和有效性.
A series Z-source dual output two-stage matrix converter (ZS-DO-TSMC) topology with its modulation strategy was proposed. Compared with conventional dual-output two-stage matrix converter, the proposed topology has less power electronic devices, higher voltage transfer ratio, and eliminate the dead time of the power electronic devices. This converter which consists of a rectifier stage, a series Z-source network and a five-leg inverter stage can supply for two three-phase loads independently. To keep the input voltage of the inverter stage constant, increase the modulation index of the inverter stage and reduce the capacitor voltage stress of the Z-source network by adjusting the duty cycle of the shoot-through vector dynamically, an improved space vector modulation strategy with dynamic boost factor was presented. Finally, the feasibility and validity of the proposed converter, operation principles and modulation strategies were verified by simulation and experimental result.