求高手分析此电路，两幅波形图有何区别？

提示：Both switching patterns are shown in Figure 6. The conducting switches for each interval are shown along with single phase voltage waveforms. Depending on which switches conduct, a closed circuit is formed including the DC capacitor and different combinations of the machine phases. Both generate similar fundamental voltage sine waves. The magnitude of the three switch scheme is slightly higher, at 2VDC/pi = 0.637VDC, versus sqrt(3)VDC/pi= 0.551VDC for the simpler two switch scheme.